JP2022064098A - Frame synchronization device, measurement device and measurement system equipped with frame synchronization device, and frame synchronization method and measurement method - Google Patents

Abstract

To provide a frame synchronization device capable of efficiently performing frame synchronization and shortening a measurement time even when an external trigger for frame synchronization cannot be used.SOLUTION: A frame synchronization device includes a processing unit setting unit 23 that sets the sum of one frame as a data processing unit and an allowable amount of frame timing deviation, a data acquisition unit 22 that acquires a data column e of a processing unit from an input signal, a reference data column storage unit 26 that stores a data column of a known symbol as a reference data column, a correlation value calculation unit 27 that calculates a correlation value between a data column r in a range of the same data number as a reference data column from the reference position in the data column e and a reference data column s each time the reference position is sequentially shifted in the data column e, and a frame timing detection unit 29 that detects frame timing on the basis of the correlation value. The processing unit setting unit 23 sets the time length of the sum of one frame and one subframe as the processing unit.SELECTED DRAWING: Figure 1

Description

The present invention relates to a frame synchronization device for detecting the frame timing of an input signal, a measurement device and a measurement system including the frame synchronization device, and a frame synchronization method and a measurement method.

Conventionally, under test conditions specified in communication standards such as LTE (Long Term Evolution) and 5G NR (New Radio), transmission is performed from a device under test (DUT (Device Under Test)) such as a device installed in a base station. A transmission test is being conducted to check the transmission performance of the DUT by receiving and analyzing the signal.

For example, in 5G NR, one frame is composed of 10 subframes, and one frame length is specified to be 10 milliseconds. However, since the frame position in the transmission signal transmitted from the DUT is unknown, it is necessary to first detect the frame timing and synchronize the frame in the transmission test.

As a method of taking frame synchronization, there is a method of using an external trigger signal indicating the frame timing. The position of the frame in the input signal is specified based on the external trigger signal.

As another method of frame synchronization, a reference frame consisting of the same data string as the known frame included in the input signal is prepared in advance, and the reference frame to be compared is sequentially shifted on the time axis with respect to the input signal. There is a so-called sliding correlation method that correlates the corresponding portion of the input signal with the reference frame (see, for example, Patent Document 1).

Patent Document 1 discloses a frame synchronization device that detects a frame head position based on a correlation value obtained by performing a correlation operation between an input signal and a reference frame.

Japanese Unexamined Patent Publication No. 2019-102925

The DUT in the transmission test is often a device under development. In the device under development, the external trigger for frame synchronization may not be accurate or may not be available. When the external trigger cannot be used in this way, the timing of the frame is unknown. Therefore, in the conventional method as described in Patent Document 1, a block of one frame is found from the captured signals and synchronized. In order to perform "frame synchronization", it was necessary to capture at least 2 frames (20 subframes) + α time length. Here, α is the time length of the presample and the postsample. FIG. 8 is a diagram showing a data structure captured by a receiving unit of a conventional measuring device. Since the reference frame for one frame is used, it can be seen that the data for two frames is required for the sliding frame synchronization process. As described above, in the conventional method of capturing data for two frames, it takes time to capture, and it takes time to transfer the captured waveform data, so that there is a problem that the measurement time becomes long.

The present invention has been made to solve the conventional problems, and even when an external trigger for frame synchronization cannot be used, frame synchronization can be efficiently performed and the measurement time can be shortened. It is an object of the present invention to provide an apparatus, a measuring apparatus and a measuring system provided with the apparatus, and a frame synchronization method and a measuring method.

The frame synchronization device of the present invention is a frame synchronization device (20) that detects the frame timing of an input signal including a known symbol at a specific position in the frame, and is a frame timing deviation from one frame as a data processing unit. A processing unit setting unit (23) that sets the sum with the allowable amount of the data, a data acquisition unit (22) that acquires a data string for the set processing unit from the input signal, and a data string of the known symbol. The reference data string storage unit (26) that stores at least a part of the same data string as the reference data string and the reference position that serves as a reference in the data string acquired by the data acquisition unit are determined and the reference position is determined. The reference position shift unit (28) that sequentially shifts at the data interval of the above, and the reference position from the reference position among the data strings acquired by the data acquisition unit each time the reference position is shifted by the reference position shift unit. The correlation value calculation unit (27) that calculates the correlation value by performing a correlation calculation between the data string in the range of the same number of data as the data string and the reference data string, and the frame timing based on the correlation value. The frame timing detection unit (29) for detecting is provided, and the processing unit setting unit performs the processing for a time length equal to or greater than the sum of one frame and the reference data string and less than or equal to the sum of one frame and one subframe. It is characterized by being set as a unit.

As described above, in the frame synchronization device of the present invention, the processing unit setting unit sets the time length as the processing unit, which is equal to or greater than the sum of one frame and the reference data string and less than or equal to the sum of one frame and one subframe. , The data acquisition unit acquires the data string (waveform data) of the processing unit, and the correlation value calculation unit performs the correlation processing with the reference data string of one symbol length or less in the acquired data string for the processing unit. It has become like. With this configuration, it is possible to shorten the data processing unit in the frame synchronization process while limiting the allowable amount of frame timing deviation to one subframe at the maximum. Therefore, even when an external trigger for frame synchronization cannot be used, frame synchronization can be performed efficiently, and when the frame synchronization device is used for the measuring device, the measurement time can be shortened.

Further, in the frame synchronization device of the present invention, the processing unit setting unit sets the minimum time length as the processing unit among the time lengths equal to or greater than the sum of one frame and the reference data string and which is an integral multiple of the slot. It may be configured to be used.

With this configuration, the frame synchronization device of the present invention can perform correlation processing on the entire range of one frame of the signal acquired by the data acquisition unit, so that the frame timing can be reliably detected. Further, since the processing unit for performing data acquisition and correlation calculation is sufficiently shorter than the conventional two frames and can be set to the smallest integer multiple of the slots, frame synchronization can be efficiently performed. Further, by setting the processing unit to the minimum time length (for example, 1 frame + 1 slot) among the integral multiples of the slots, the frame timing deviation can be allowed up to 1 slot.

Further, in the frame synchronization device of the present invention, the processing unit setting unit sets the minimum time length as the processing unit among the time lengths equal to or greater than the sum of one frame and the reference data string and which is an integral multiple of the symbol. It may be configured to be used.

With this configuration, the frame synchronization device of the present invention can perform correlation processing on the entire range of one frame of the signal acquired by the data acquisition unit, so that the frame timing can be reliably detected. Further, since the processing unit for performing data acquisition and correlation calculation is sufficiently shorter than the conventional two frames and can be set to the smallest one among integer multiples of the symbol, frame synchronization can be efficiently performed. Further, by setting the processing unit to the minimum time length (for example, 1 frame + 1 symbol) among the integral multiples of the symbols, the frame timing deviation can be allowed up to 1 symbol.

Further, the frame synchronization device of the present invention may be configured such that the processing unit setting unit sets the time length of the sum of one frame and the reference data string as the processing unit.

With this configuration, the frame synchronization device of the present invention can perform correlation processing on the entire range of one frame of the signal acquired by the data acquisition unit, so that the frame timing can be reliably detected. Further, since the processing unit for data acquisition and correlation calculation can be set to be sufficiently shorter and the minimum than the conventional two frames, frame synchronization can be efficiently performed.

Further, in the frame synchronization device of the present invention, the processing unit setting unit is equal to or greater than the sum of (A) one frame and the reference data string and is a subframe based on the frame timing detection result by the frame timing detection unit. The minimum time length out of an integral multiple of the time length, (B) the minimum time length out of the sum of one frame and the reference data string and an integral multiple of the slot, (C) one frame. And the minimum time length of the time length equal to or more than the sum of the reference data string and an integral multiple of the symbol, and (D) one of the time lengths of the sum of one frame and the reference data string. It may be configured to be set as the processing unit.

With this configuration, the frame synchronization device of the present invention changes the data processing unit based on the frame timing detection result, so that the frame timing can be reliably detected and the data processing unit is set to the optimum time length. Can be set.

Further, the frame synchronization device of the present invention further includes a symbol length acquisition unit (24) for acquiring information on the symbol length of the symbol included in the input signal, and the processing unit setting unit is acquired by the symbol length acquisition unit. The processing unit may be set based on the information of the symbol length.

With this configuration, in the frame synchronization device of the present invention, the processing unit setting unit sets the processing unit based on the symbol length information acquired by the symbol length acquisition unit, so that the subcarrier interval and bandwidth are set under the communication standard. Even if the symbol length changes due to parameters such as, it can be easily adapted.

Further, in the frame synchronization apparatus of the present invention, the reference data string storage unit may be configured to store a part of the same data string as the data string of the known symbol as a reference data string.

With this configuration, the frame synchronization device of the present invention can make the reference data string shorter than one symbol length. For example, when the time length of the sum of one frame and the reference data string is set as the processing unit, the processing unit is set. Since it can be set to the minimum, frame synchronization can be performed efficiently.

The measuring device of the present invention down-converts and samples the signal from the object to be measured, acquires the receiving unit (10) that captures the data string of the processing unit, and acquires the captured data string to detect the frame timing. The frame synchronization device (20) according to any one of the above, a demodulation unit (31) that demolishes the signal of the captured data string based on the frame timing detected by the frame synchronization device, and the demodulation. It is characterized by including a measuring unit (32) for measuring signal characteristics.

With this configuration, since the measuring device of the present invention includes the frame synchronization device, it is possible to shorten the processing unit of the signal acquired by the data acquisition unit and performed by the correlation value calculation unit. Therefore, even when the external trigger for frame synchronization cannot be used, frame synchronization can be performed efficiently and the measurement time can be shortened.

The measuring system of the present invention is a measuring system (100) including a receiving device (110) and a data processing device (120) connected to the receiving device by a communication network (130), and the receiving device is the receiving device. , A down converter (11) that down-converts the received signal, an A / D conversion unit (12) that A / D-converts the down-converted signal, and orthogonal demodulation that orthogonally demolishes the A / D-converted signal. The unit (13), the data capture unit (14) that captures the data string of the processing unit from the orthogonally demodulated signal, and the captured data string are transmitted to the data processing apparatus via the communication network. The data processing device includes a receiving unit (122) for receiving a data string transmitted from the transmitting unit of the receiving device, and a frame by acquiring the received data string. The frame synchronization device according to any one of the above for detecting the timing, the demodulation unit (31) for demolishing the signal of the captured data string based on the frame timing detected by the frame synchronization device, and the demodulation. It is characterized by including a measuring unit (32) for measuring signal characteristics.

With this configuration, in the measurement system of the present invention, the time length (processing unit) of the signal captured by the data capture unit of the receiving device is the same as the data processing unit for performing data acquisition and correlation calculation in the data processing device. , Can be shortened compared to the conventional technique. As a result, the amount of data transferred from the receiving device to the data processing device can be suppressed to the minimum amount required for frame synchronization, so that the transfer time can be shortened. Therefore, even when the receiving device and the data processing device are connected by a communication network such as a LAN, frame synchronization can be efficiently performed and the measurement time can be shortened.

The frame synchronization method of the present invention is a frame synchronization method for detecting the frame timing of an input signal including a known symbol at a specific position in the frame, and is a permissible amount of deviation between one frame and a frame timing as a data processing unit. A processing unit setting step (S2) for setting the sum of A reference data string storage step (S3) for storing at least a part as a reference data string and a reference reference position as a reference in the data string acquired in the data acquisition step are determined, and the reference position is sequentially shifted at a predetermined data interval. The same data as the reference data string from the reference position among the data strings acquired in the data acquisition step each time the reference position is shifted in the reference position shift step (S13) to be performed and the reference position shift step. A correlation value calculation step (S11) for calculating a correlation value by performing a correlation calculation between a data string in a range of numbers and the reference data string, and a frame timing detection for detecting the frame timing based on the correlation value. In the processing unit setting step including steps (S12, S14), a time length equal to or greater than the sum of one frame and the reference data string and less than or equal to the sum of one frame and one subframe is set as the processing unit. It is characterized by doing.

As described above, in the frame synchronization method of the present invention, in the processing unit setting step, a time length equal to or greater than the sum of one frame and the reference data string and less than or equal to the sum of one frame and one subframe is set as the processing unit. , In the data acquisition step, the data string (waveform data) of the processing unit is acquired, and in the correlation value calculation step, the data string for the acquired processing unit is subjected to the correlation processing with the reference data string of 1 symbol length or less. It is supposed to do. With this configuration, it is possible to shorten the data processing unit in the frame synchronization process while limiting the allowable amount of frame timing deviation to one subframe at the maximum. Therefore, even when an external trigger for frame synchronization cannot be used, frame synchronization can be performed efficiently, and when the frame synchronization device is used for the measuring device, the measurement time can be shortened. Further, by setting the processing unit to, for example, 1 frame + 1 subframe, a frame timing shift can be tolerated up to 1 subframe.

In the measurement method of the present invention, the reception step (S4) of down-converting and sampling the signal from the object to be measured to capture the data string of the processing unit and the captured data string are acquired to detect the frame timing. The demodulation step (S15) for demodulating the signal of the data string captured in the reception step based on the frame synchronization method and the frame timing detected by the frame synchronization method, and the characteristics of the demodulated signal. It is characterized by including a measurement step (S16) for measuring.

With this configuration, since the measurement method of the present invention includes the frame synchronization method, it is possible to shorten the processing unit of the signal acquired in the data acquisition step and the correlation calculation is performed in the correlation value calculation step. Therefore, even when the external trigger for frame synchronization cannot be used, frame synchronization can be performed efficiently and the measurement time can be shortened.

The measuring method of the present invention is a measuring method by a measuring system (100) including a receiving device (110) and a data processing device (120) connected to the receiving device by a communication network (130). In the receiving device, the received signal is down-converted (S5), the down-converted signal is A / D converted (S6), the A / D-converted signal is orthogonally demodulated (S7), and the orthogonally demolished. The data string of the processing unit is captured from the signal (S8), the captured data string of the processing unit is transmitted to the data processing device via the communication network (S9), and the data processing device is used. The above-mentioned frame synchronization method of receiving the data string of the processing unit transmitted from the receiving device and acquiring the received data string to detect the frame timing is performed, and the detection is performed by the frame synchronization method. It is characterized by including demodating the signal of the captured data string (S15) and measuring the characteristics of the demolished signal (S16) based on the frame timing.

With this configuration, in the measurement method of the present invention, the time length (processing unit) of the signal captured by the receiving device is made the same as the data processing unit for data acquisition and correlation calculation in the data processing device, which is shorter than the conventional technique. can do. As a result, the amount of data to be transferred from the receiving device to the data processing device can be suppressed to the amount required for frame synchronization, so that the transfer time can be shortened. Therefore, even when the receiving device and the data processing device are connected by a communication network such as a LAN, frame synchronization can be efficiently performed and the measurement time can be shortened.

According to the present invention, a frame synchronization device capable of efficiently performing frame synchronization and shortening the measurement time even when an external trigger for frame synchronization cannot be used, and a measurement device and a measurement system provided with the frame synchronization device. Also, a frame synchronization method and a measurement method can be provided.

It is a block diagram which shows the structure of the measuring apparatus which concerns on 1st Embodiment of this invention. It is a figure which shows the structure of the data which is captured by the receiving part of the measuring apparatus of FIG. It is a figure which shows the correlation processing in the frame synchronization apparatus of FIG. It is a figure which shows the flowchart of the measurement method which concerns on 1st Embodiment of this invention. It is a block diagram which shows the structure of the measurement system which concerns on 2nd Embodiment of this invention. It is a figure which shows the usage mode of the measurement system of FIG. It is a figure which shows the flowchart of the measurement method which concerns on the 2nd Embodiment of this invention. It is a figure which shows the structure of the data which is captured by the receiving part of the conventional measuring apparatus.

(First Embodiment)
The first embodiment of the present invention will be described with reference to the drawings.

The measuring device 1 according to the first embodiment of the present invention tests the transmission performance of the DUT 2 by receiving the modulated signal a transmitted from the measurement object (DUT) 2 and demodulating it to measure the signal characteristics. It is a thing. Therefore, as shown in FIG. 1, the measuring device 1 includes a receiving unit 10, a frame synchronization device 20, a signal processing unit 30, a display unit 40, an operating unit 50, and a control unit 60.

The DUT2 is not limited, and examples thereof include RRH (Remote Radio Head) of a radio base station. The modulated signal a transmitted from the DUT 2 is an OFDM modulated signal modulated by, for example, an orthogonal frequency division multiplexing (OFDM) method according to a communication standard such as LTE, LTE-Advanced, 5G NR, and wireless LAN. The modulated signal a is also referred to as a measured signal. The OFDM modulation signal is obtained by performing OFDM modulation, up-conversion, etc. on the data series in which a known data string (synchronization symbol) is inserted at a specific position on the time axis in the frame on the transmission side (DUT2). It is a signal that was given. In the present embodiment, 5G NR is assumed as the communication standard, and the modulation signal modulated by the OFDM method is received, but the communication standard and the modulation method are not limited thereto. Hereinafter, each component will be described.

(Receiver)
The receiving unit 10 receives the modulation signal a (OFDM modulation signal) transmitted from the DUT 2 via an antenna or by wire, down-converts and samples the modulation signal a, and captures the signal of the data string of the processing unit. There is. Specifically, the receiving unit 10 includes a down converter 11, an analog-to-digital conversion unit (A / D conversion unit) 12, an orthogonal demodulation unit 13, and a data capture unit 14. Here, the processing unit is the amount of data handled at one time in processing such as data capture, transfer, and frame synchronization, and is represented by the time length or the data length (number of data, number of samples, etc.).

The down converter 11 includes a mixer and a local oscillator, inputs the modulated signal a transmitted from the DUT 2 and the local signal generated by the local oscillator to the mixer, down-converts them, and outputs an intermediate frequency (IF) signal b. It is designed to generate. The intermediate frequency signal b is sent to the A / D conversion unit 12.

The A / D conversion unit 12 samples the intermediate frequency signal b frequency-converted by the down converter 11 and converts it from an analog signal to a digital signal. The obtained digital intermediate frequency signal c is sent to the orthogonal demodulation unit 13.

The orthogonal demodulation unit 13 frequency-converts the digital intermediate frequency signal c output from the A / D conversion unit 12 into a baseband signal, and at the same time, performs orthogonal demodulation to the I-phase component and the Q-phase component. The obtained orthogonal demodulation signal d (also referred to as waveform data) is sent to the data capture unit 14. The orthogonal demodulation signal d is a complex signal.

The data capture unit 14 captures and stores a signal of a data string for a predetermined capture length (processing unit) from the orthogonal demodulation signal d. The captured data string (also referred to as a captured data string or simply a data string) e is sent to the frame synchronization device 20 and the signal processing unit 30.

In the above description, the receiving unit 10 is converted into an intermediate frequency signal in the down converter 11, but it may be converted into a baseband signal in the down converter 11.

The frame synchronization device 20 detects the frame timing of the captured data string e captured by the data capture unit 14, and outputs the frame timing signal h indicating the detection to the signal processing unit 30. The frame synchronization device 20 will be described in detail later. The captured data string e captured by the data capture unit 14 is an input signal of the frame synchronization device 20.

(Signal processing unit)
The signal processing unit 30 is adapted to perform OFDM demodulation of the captured data string e captured by the data capture unit 14 of the receiving unit 10 to acquire an OFDM demodulated signal f, and execute various measurements. Specifically, the signal processing unit 30 includes an OFDM demodulation unit 31 and a measurement unit 32.

The OFDM demodulation unit 31 is adapted to input the captured data string e captured by the data capture unit 14 and the frame timing signal h output by the frame synchronization device 20. Then, the OFDM demodulation unit 31 performs OFDM demodulation processing such as FFT (Fast Fourier Transform) processing and subcarrier demodulation on the captured data string e based on the frame timing signal h to generate the OFDM demodulation signal f. It has become. The generated OFDM demodulated signal f is sent to the measuring unit 32. The OFDM demodulation unit 31 in the present embodiment corresponds to the demodulation unit of the present invention.

If necessary, CP (Cyclic Prefix) is removed from each symbol of the capture data string e before the FFT process is performed by the OFDM demodulation unit 31.

The measuring unit 32 is configured to measure and analyze, for example, a frequency error, a timing error, an EVM (Error Vector Magnitude), a transmission power, a constellation, etc. with respect to the OFDM demodulation signal f output by the OFDM demodulation unit 31. ing. The information g of the measurement and analysis results by the measuring unit 32 is sent to the display unit 40.

(Display unit, operation unit, control unit)
The display unit 40 includes a display device such as a liquid crystal display, and displays the test result of the DUT 2 on the display device, including data and graphs of measurement and analysis results sent from the measurement unit 32. ..

The operation unit 50 is operated by the user to set various parameters in addition to the measurement items, measurement conditions, and determination conditions when testing the DUT2. Specifically, the operation unit 50 is composed of, for example, a keyboard composed of a touch panel and hardware keys, an input device such as a mouse or a dial, and a control circuit for controlling these.

The control unit 60 receives input from the operation unit 50, sets various parameters and the like, and controls functional units such as the reception unit 10, the frame synchronization device 20, the signal processing unit 30, and the display unit 40. ing.

[Frame sync device]
Next, the configuration of the frame synchronization device 20 will be described.

The frame synchronization device 20 detects the frame timing from the capture data string e (complex data string for the processing unit) which is an input signal to the frame synchronization device 20. Specifically, the frame synchronization device 20 is adapted to detect the frame timing of an input signal including a known symbol at a specific position in the frame. Therefore, as shown in FIG. 1, the frame synchronization device 20 includes a correlation processing unit 21, a reference position shift unit 28, a frame timing detection unit 29, and a threshold storage unit 291.

The correlation processing unit 21 acquires the capture data string e, which is a complex data sequence for the processing unit obtained by the reception unit 10, and the correlation value between the partial data string r cut out from the capture data string e and the reference data string s. The frame timing is detected by calculating. Therefore, the correlation processing unit 21 includes a data acquisition unit 22, a processing unit setting unit 23, a symbol length acquisition unit 24, a reference data string calculation unit 25, a reference data string storage unit 26, and a correlation value calculation unit 27. ..

The symbol length acquisition unit 24 acquires information on the symbol length of the symbol included in the capture data string e as an input signal to the frame synchronization device 20. Specifically, the symbol length acquisition unit 24 acquires information on the symbol length conforming to the communication standard based on parameters such as the subcarrier interval and the frequency bandwidth, and sets it as a parameter. Parameters such as the subcarrier interval and the frequency bandwidth are preset by the user or automatically set by the measuring device 1. The symbol length information is sent to the processing unit setting unit 23 and the reference data string calculation unit 25.

The processing unit setting unit 23 sets the sum of one frame and the permissible amount of frame timing deviation as a data processing unit in processing such as data capture and frame synchronization. Specifically, the processing unit setting unit 23 sets the time length as the processing unit, which is equal to or greater than the sum of one frame and the reference data string and less than or equal to the sum of one frame and one subframe. For example, the processing unit setting unit 23 may set the time length of the sum of one frame and one subframe as the processing unit. By setting the processing unit to, for example, 1 frame + 1 subframe, the allowable amount of frame timing deviation is limited to 1 subframe at the maximum. In other words, if the frame timing deviation is within one subframe, the frame timing can be appropriately detected. The information of the processing unit L is sent to the data capture unit 14 and the data acquisition unit 22.

The processing unit setting unit 23 may be configured to set the minimum time length as the processing unit, which is equal to or greater than the sum of one frame and the reference data string and is an integral multiple of the slot. For example, the processing unit setting unit 23 may set the sum of one frame and one slot as the processing unit. By setting the processing unit to the minimum time length (for example, 1 frame + 1 slot) among the integral multiples of the slots, the allowable amount of frame timing deviation is limited to 1 slot at the maximum.

In the present embodiment, the data processing unit is set, but the data processing unit is not limited to this, and the data processing unit is fixed to a fixed value such as the sum of one frame and one subframe. You may.

The data acquisition unit 22 acquires the capture data string e of the processing unit L sent from the data capture unit 14 of the reception unit 10. The data processing unit handled by the data capture unit 14 in the receiving unit 10 and the data processing unit in the frame synchronization device 20 are the same. In the capture data string e of the processing unit L acquired by the data acquisition unit 22, a data string having the same number of data as the reference data string is cut out as a partial data string r and sent to the correlation value calculation unit 27.

The reference data string calculation unit 25 calculates the reference data string s based on the symbol length of the symbol included in the input signal, and stores it in the reference data string storage unit 26. Specifically, the reference data string calculation unit 25 calculates the reference data string s using information of various parameters such as the symbol length acquired by the symbol length acquisition unit 24, for example, according to the communication standard. .. For the communication standard, refer to, for example, 7.4.1.1 Demodulation reference signals for PDSCH of 3GPP TS 38.211. With this configuration, the frame synchronization device 20 can obtain an appropriate reference data string even if the symbol length changes due to parameters such as the subcarrier interval and the frequency bandwidth under the communication standard.

The reference data string storage unit 26 stores at least a part of the same data string as the data string of the known symbol existing at a specific position in the frame as the reference data string s. Specifically, the reference data string storage unit 26 stores the reference data string s calculated by the reference data string calculation unit 25. The reference data string s is sent to the correlation value calculation unit 27.

The reference position shift unit 28 determines a reference reference position in the capture data string e for the processing unit acquired by the data acquisition unit 22, and sequentially shifts the reference position at predetermined data intervals. The data interval may be one sample or a plurality of two or more samples.

The correlation value calculation unit 27 has the same number of data (samples) as the reference data string s from the reference position in the capture data string e acquired by the data acquisition unit 22 each time the reference position is shifted by the reference position shift unit 28. A known correlation calculation is performed between the partial data string r of the range and the reference data string s to calculate the correlation value (or correlation coefficient). The calculated correlation value is sent to the frame timing detection unit 29.

The threshold value storage unit 291 is adapted to store a threshold value for detecting the timing (for example, the position of a known symbol) of a frame included in the capture data string e. The threshold value stored in the threshold value storage unit 291 may be determined by, for example, an experiment or a simulation.

The frame timing detection unit 29 detects the frame timing based on the correlation value calculated by the correlation value calculation unit 27. Specifically, the correlation value calculated by the correlation value calculation unit 27 is compared with the threshold value stored in the threshold value storage unit 291. Then, the frame timing detection unit 29 outputs the frame timing signal h indicating that the frame timing has been detected to the OFDM demodulation unit 31 when the correlation value exceeds the threshold value.

<Data structure>
Here, the data structure of the captured data string e (data string for processing units) captured by the data capture unit 14 of the receiving unit 10 will be described with reference to FIG. FIG. 2 assumes, as an example, that the processing unit is 11 subframes.

First, the modulation signal a transmitted from the DUT 2 is composed of a plurality of continuous frames when viewed in the time axis direction, and one frame is composed of 10 subframes. The time length of one subframe is 1 millisecond, so the time length of one frame is 10 milliseconds. The subframe is composed of one or a plurality of slots, and the number of slots included in one subframe is determined by a communication standard according to a subcarrier interval, a frequency bandwidth, and the like. One slot contains, for example, 14 symbols.

When viewed in the frequency axis direction, the modulation signal a is composed of a plurality of resource blocks (RB (Resource Block)), and one resource block includes, for example, 12 consecutive subcarriers. The resource block corresponds to, for example, a range on the time-frequency axis defined by 12 subcarriers on the frequency axis and one slot on the time axis. One resource block contains, for example, 12 × 14 = 168 resource elements (RE (Resource Element)).

As shown in FIG. 2, the captured data string captured by the data capture unit 14 of the receiving unit 10 has a data length (time length) equal to the sum of one frame, one subframe, a presample, and a postsample. ing.
Time length of capture data string = 1 frame + 1 subframe + α
Here, α is the data length of the presample and the postsample.

Here, the pre-sample and the post-sample are the glue allowance required when performing pretreatment such as filtering. In other words, in order to suppress the transient response that occurs when filtering that limits the band to only the measurement signal, extra α / 2 data is captured before and after the data string. Such filtering may be performed in the frame synchronization device 20.

In the following description, it is not specified that the captured data column contains presample and postsample, but it is assumed that the actually captured data column contains presample and postsample. .. For example, in the present specification and claims, the term "processing unit" indicates a data string excluding presamples and postsamples. For example, when it is described that the processing unit is the sum of 1 frame and 1 subframe, the data string actually captured at one time has a data length of 1 frame + 1 subframe + α. And.

Returning to FIG. 2, the captured data string e captured by the data capture unit 14 of the receiving unit 10 is, for example, subframes 7, 8 and 9 of the preceding frame and subframes 0, 1 and 2 of the succeeding frame. , 3, 4, 5, 6, 7 are included. That is, it is not necessary to include all one frame, and it is sufficient to include 11 consecutive subframes in the preceding and following frames.

The data length of the capture data string e for the processing unit captured by the data capture unit 14 of the receiving unit 10 is also a processing unit in the frame synchronization processing.

As shown in FIG. 2, each subframe in the capture data sequence e contains two slots, and each slot contains, for example, 14 symbols. In FIG. 2, a demodulation reference signal (DM-RS (DeModulation Reference Signal)) peculiar to a predetermined subcarrier (RE) of the symbol 2 is included. That is, the symbol 2 is a signal consisting of a unique data string that can be identified from other symbols. Specifically, the symbol 2 is a different signal if the subframe numbers are different, and is a different signal if the slot numbers are different even in the same subframe.

In FIG. 2, the symbol 2 is a reference data string s that specifies a symbol position in the capture data string e, which is an example. Other symbols containing reference data such as DM-RS may be used as the reference data string.

Next, the correlation processing in the frame synchronization apparatus 20 will be described with reference to FIG.

FIG. 3 is a diagram showing correlation processing in the frame synchronization device 20. In FIG. 3, the correlation between the partial data string r and the reference data string s extracted from the reference position in the capture data string e for the processing unit captured by the data capture unit 14 for the same time length as the reference data string s. The value is calculated, and the frame timing is detected depending on whether or not the correlation value exceeds the threshold value. The reference position is sequentially shifted by the reference position shift unit 28 at a predetermined data interval d. The data interval d is, for example, one sample. While shifting the position of the partial data string r extracted from the capture data string e, the correlation value between the partial data string r and the reference data column s is calculated, and the frame timing is detected based on the correlation value. In FIG. 3, when the time is nt, the correlation value exceeds the threshold value, and it is determined that the partial data string r at this time is the same as the reference data string s, and the frame timing signal h is output.

When the frame timing is in the center or the middle position of the capture data string e, the frame timing can be detected even if the frame timing shift occurs to some extent. However, when the frame timing is at the position of the end of the capture data string e, if the frame timing shift occurs, the frame timing cannot be captured and may not be detected. Therefore, the time length in which the "allowable amount of frame timing shift", which is the allowable frame timing shift, is added to one frame is used as the data processing unit. Specifically, the permissible amount of frame timing deviation is, for example, a time length of not more than the reference data string and not more than one subframe. The reason why the reference data string or more is set is that the correlation processing is surely performed for the entire range of one frame in the capture data string e.

<Modification 1>
Next, a modification 1 of the first embodiment will be described.

In the first modification, the processing unit setting unit 23 sets the processing unit based on the symbol length information acquired by the symbol length acquisition unit 24. Specifically, the processing unit setting unit 23 sets the minimum time length as the processing unit among the time lengths equal to or greater than the sum of one frame and the reference data string s and which is an integral multiple of the symbol. .. For example, the processing unit setting unit 23 sets the sum of one frame and one symbol as the processing unit. By setting the processing unit to the minimum time length (for example, 1 frame + 1 symbol) among integer multiples of the subframe, the allowable amount of frame timing deviation is limited to 1 symbol at the maximum.

With this configuration, the frame synchronization device 20 can perform correlation processing for the entire range of one frame of the captured data string e captured or acquired by the data capture unit 14 and the data acquisition unit 22, so that the frame timing can be set. It can be detected reliably. Further, since the processing unit for performing data capture (acquisition) and correlation calculation can be set to be sufficiently shorter than the conventional two frames, for example, one frame + 1 symbol, frame synchronization can be efficiently performed. Further, in the frame synchronization device 20, the processing unit setting unit 23 sets the processing unit based on the symbol length information acquired by the symbol length acquisition unit 24, so that the subcarrier interval, frequency bandwidth, etc. are set under the communication standard. Even if the symbol length changes depending on the parameter of, it can be easily adapted.

<Modification 2>
Next, a modification 2 of the first embodiment will be described.

In the second modification, the reference data string storage unit 26 stores a part of the same data string as the data string of the known symbol existing at a specific position in the frame as the reference data string s. This reference data string s is a part extracted from the data string of a known symbol existing at a specific position in the frame so that it can be identified in the frame and the position in the frame can be specified. .. Further, the processing unit setting unit 23 sets the time length of the sum of one frame and the reference data string s as the processing unit.

With this configuration, the frame synchronization device 20 can make the reference data string s shorter than one symbol length, and thus the processing unit of data capture and frame synchronization can be set to be sufficiently shorter and the minimum than the conventional two frames, which is efficient. Frame synchronization can be performed.

<Modification 3>
Next, a modification 3 of the first embodiment will be described.

In the modification 3, the processing unit setting unit 23 is controlled by the control unit 60, based on the frame timing detection result by the frame timing detection unit 29.
(A) The minimum time length among the time lengths equal to or greater than the sum of one frame and the reference data string s and which is an integral multiple of the subframe.
(B) The minimum time length of the time length equal to or greater than the sum of one frame and the reference data string s and which is an integral multiple of the slot.
(C) The minimum time length of the sum of one frame and the reference data string s or more and an integral multiple of the symbol, and (D) the time length of the sum of one frame and the reference data string s.
Any one of these is set as the processing unit.

For example, if the processing unit is 1 frame + 1 symbol and the frame timing detection result is good, 1 frame + 1 symbol is set as the processing unit, and if the frame timing detection result is not good, the processing unit is set as 1 frame + 1 slot. Check the frame timing detection result. If the frame timing detection result is good, 1 frame + 1 slot is set as the processing unit, and if the frame timing detection result is not good, the processing unit is set to 1 frame + 1 subframe. The quality of the frame timing detection result may be judged from the viewpoint of detection stability, certainty, accuracy, and the like.

With this configuration, the frame synchronization device 20 changes the data processing unit based on the frame timing detection result, so that the frame timing can be reliably detected and the data processing unit is set to the optimum time length. be able to.

The measuring device 1 and the frame synchronization device 20 according to the first embodiment are, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), an input / output interface, a storage device such as a hard disk, and the like. It is equipped with computers individually or as a whole. As a result, for example, some or all of the functions of the receiving unit 10, the frame synchronization device 20, the signal processing unit 30, the display unit 40, the operation unit 50, the control unit 60, and the like are various processes stored in the ROM or the storage device. This can be achieved by reading the program into RAM and executing it on the CPU.

The frame synchronization device 20 may be integrally incorporated in the measuring device 1 and may be configured to share the computer with the measuring device 1. Further, the frame synchronization device 20 may be application software (program) installed in the computer of the measuring device 1.

Next, the measurement method according to the present embodiment will be described with reference to FIG.

The symbol length acquisition unit 24 acquires information on the symbol length of the symbol included in the capture data string e as an input signal to the frame synchronization device 20 (step S1). Specifically, the symbol length acquisition unit 24 acquires information on the symbol length conforming to the communication standard based on parameters such as the subcarrier interval and the frequency bandwidth.

The processing unit setting unit 23 sets the sum of one frame and the permissible amount of frame timing deviation as the data processing unit in processing such as data capture and frame synchronization (step S2). For example, the processing unit setting unit 23 sets the time length of 1 frame + 1 subframe as the processing unit, or sets the time length of 1 frame + 1 slot. When setting the time length of 1 frame + 1 subframe as the processing unit, the time length specified in the communication standard is set (11 milliseconds). When setting the time length of 1 frame + 1 slot as the processing unit, the processing unit is calculated using the information of the symbol length acquired by the symbol length acquisition unit 24.

When the time length of the reference data string s is shorter than one symbol, the processing unit setting unit 23 may set the time length of one frame + the reference data string s as the processing unit.

The reference data string calculation unit 25 calculates the reference data string s based on the symbol length of the symbol included in the input signal, and stores it in the reference data string storage unit 26 (step S3). Specifically, the reference data string calculation unit 25 calculates the reference data string s using the information of various parameters such as the symbol length acquired by the symbol length acquisition unit 24 according to the communication standard such as 3GPP TS38.211. ..

The reference data string storage unit 26 stores the reference data string s calculated by the reference data string calculation unit 25. This reference data string s is the same as a known symbol existing at a specific position in the frame included in the capture data string e.

The DUT2 transmits an OFDM modulated signal modulated by, for example, an OFDM method according to a communication standard such as 5G NR. The receiving unit 10 receives the modulated signal a transmitted from the DUT 2 (step S4).

The down converter 11 down-converts the modulation signal a transmitted from the DUT 2 to generate an intermediate frequency (IF) signal b (step S5).

The A / D conversion unit 12 samples the intermediate frequency signal b frequency-converted by the down converter 11 and converts it from an analog signal to a digital signal (step S6). The A / D conversion unit 12 sends the obtained digital intermediate frequency signal c to the orthogonal demodulation unit 13.

The orthogonal demodulation unit 13 frequency-converts the digital intermediate frequency signal c output from the A / D conversion unit 12 into a baseband signal, and at the same time, performs orthogonal demodulation to the I-phase component and the Q-phase component (step S7).

The data capture unit 14 captures and stores the capture data string e for a predetermined processing unit from the orthogonal demodulation signal d (step S8). The processing unit L is a value set by the processing unit setting unit 23.

The data acquisition unit 22 acquires the capture data string e of the processing unit L sent from the data capture unit 14 of the reception unit 10. The data length of the capture data string e acquired by the data acquisition unit 22 is the processing unit L set by the processing unit setting unit 23, that is, the capture data string e captured by the data capture unit 14 of the reception unit 10. It is the same as the data length of.

The reference position shift unit 28 sets a reference reference position in the capture data string e for the processing unit acquired by the data acquisition unit 22. The reference position is the head position of the partial data string r in which the correlation processing is performed with respect to the reference data string s in the capture data string e of the processing unit. For example, the reference position shift unit 28 defines the time t0 (or the sample corresponding to the time t0) of the capture data string e shown in FIG. 3 as the reference position.

The correlation value calculation unit 27 is a portion in the range of the same number of samples as the reference data string s from the reference position in the capture data string e acquired by the data acquisition unit 22 each time the reference position is shifted by the reference position shift unit 28. A known correlation calculation is performed between the data string r and the reference data string s to calculate a correlation value (or correlation coefficient) (step S11).

The threshold value storage unit 291 stores a threshold value for detecting the timing of the frame included in the capture data string e.

The frame timing detection unit 29 detects the frame timing based on the correlation value calculated by the correlation value calculation unit 27. Specifically, the correlation value calculated by the correlation value calculation unit 27 is compared with the threshold value stored in the threshold value storage unit 291 (step S12). Then, when the correlation value exceeds the threshold value (YES in step S12), the frame timing detection unit 29 outputs the frame timing signal h indicating that the frame timing has been detected to the OFDM demodulation unit 31 (step S14).

On the other hand, when the correlation value does not exceed the threshold value (NO in step S12), the reference position shift unit 28 shifts the reference reference position in the captured data string e of the captured processing unit by one sample (step). S13), the process returns to step S11.

Based on the frame timing signal h, the OFDM demodulation unit 31 performs OFDM demodulation processing such as FFT processing and subcarrier demodulation on the captured data string e captured by the data capture unit 14 to generate an OFDM demodulation signal f. , Output to the measuring unit 32 (step S15).

The measuring unit 32 measures and analyzes, for example, a frequency error, a timing error, an EVM, a transmission power, a constellation, and the like with respect to the OFDM demodulation signal f output by the OFDM demodulation unit 31 (step S16).

The display unit 40 displays the test result of the DUT 2 on the display device, including the measurement and analysis result data and graphs sent from the measurement unit 32 (step S17).

As described above, in the frame synchronization device 20 and the measurement device 1 according to the present embodiment, the processing unit setting unit 23 sets, for example, the time length of 1 frame + 1 subframe as the data processing unit, and the data acquisition unit 22 sets the time length. , The capture data string e for the processing unit is acquired, and the correlation value calculation unit 27 performs the correlation processing with the reference data string s of one symbol length or less in the acquired capture data string e for the processing unit. It has become. With this configuration, the correlation processing can be performed on the entire range of one frame of the signal acquired by the data acquisition unit 22, so that the frame timing can be reliably detected. In addition, the processing unit for performing data capture and correlation calculation can be set sufficiently shorter than the conventional two frames. Therefore, even if an external trigger for frame synchronization cannot be used, frame synchronization can be efficiently performed while limiting the allowable amount of frame timing deviation to one subframe at the maximum, and the measurement time is shortened. can do.

(Second embodiment)
Next, the measurement system 100 according to the second embodiment of the present invention will be described.

The measuring system 100 according to the second embodiment is a measuring device according to the first embodiment in that the receiving device 110 and the data processing device 120 are connected by a communication network 130 such as a LAN (Local Area Network). It is different from 1. The same components are designated by the same reference numerals, and detailed description thereof will be omitted as appropriate.

The measurement system 100 according to the present embodiment receives and captures the modulation signal a transmitted from the DUT 2 in the receiving device 110, demodulates it in the data processing device 120, and measures the signal characteristics to improve the transmission performance of the DUT 2. It is to be tested. As shown in FIG. 5, the measurement system 100 includes a receiving device 110, a data processing device 120, and a communication network 130 such as a LAN that connects the receiving device and the data processing device 120.

(Receiver)
The receiving device 110 receives and captures the modulated signal a transmitted from the DUT 2, and transmits the captured capture data string e to the data processing device 120. Therefore, the receiving device 110 includes a down converter 11, an A / D conversion unit 12, an orthogonal demodulation unit 13, a data capture unit 14, and a transmission / reception unit 112.

The down converter 11 down-converts the received modulation signal a. The A / D conversion unit 12 A / D converts the down-converted signal. The orthogonal demodulation unit 13 orthogonally demodulates the A / D converted signal. The data capture unit 14 captures a data string (capture data string) e for a predetermined processing unit from the signal demodulated orthogonally.

The transmission / reception unit 112 transmits the capture data string e to the data processing device 120 via the communication network 130. Further, the transmission / reception unit 112 is adapted to receive necessary parameter information sent from the data processing device 120, such as information on the processing unit L. The transmission / reception unit 112 of the present embodiment corresponds to the transmission unit of the present invention.

(Data processing device)
The data processing device 120 receives the captured data string e, performs frame synchronization and OFDM demodulation on the captured data string e, and then performs various measurements. Therefore, the data processing device 120 includes a transmission / reception unit 122, a frame synchronization device 20, an OFDM demodulation unit 31, a measurement unit 32, a display unit 40, an operation unit 50, and a control unit 60.

The transmission / reception unit 122 receives the capture data string e sent from the transmission / reception unit 112 of the reception device 110. Further, the transmission / reception unit 122 transmits the information of the processing unit L set by the processing unit setting unit 23 of the frame synchronization device 20 to the reception device 110. The transmission / reception unit 122 of the present embodiment corresponds to the reception unit of the present invention.

The frame synchronization device 20 detects the frame timing based on the received capture data string e. The OFDM demodulation unit 31 demodulates the capture data string e based on the frame timing detected by the frame synchronization device 20. The measuring unit 32 measures the characteristics of the demodulated signal. The display unit 40 displays the result of measurement by the measurement unit 32 and the like.

The signal length of the captured data string e captured by the data capture unit 14 of the receiving device 110 becomes equal to the time length of the captured data string e acquired by the data acquisition unit 22 of the frame synchronization device 20 in the data processing device 120. There is.

FIG. 6 is a diagram showing a usage mode of the measurement system 100 according to the present embodiment. As shown in FIG. 6, the signal transmitted from the DUT2 (RRH) installed in the OTA (Over The Air) chamber 200 is sent to the measurement system 100 via the antenna 201 and the RF switch 202. The signal transmitted from DUT2 is, for example, a millimeter wave or a sub 6 GHz band (Sub6) signal.

In the measurement system 100, the receiving device 110 and the data processing device 120 are connected by a communication network 130. In FIG. 6, an RF converter 11a is provided between the RF switch 202 and the data processing device 120. The receiving device 110 transmits the captured data string e, which is the captured I / Q data, to the data processing device 120 via the communication network 130. Further, the receiving device 110 is adapted to transmit a control signal for controlling the RF switch 202 and the DUT2.

In FIG. 6, the signal transmitted from the DUT 2 set in the OTA chamber 200 is input to the measurement system 100 via the antenna 201 and the RF switch 202, but the present invention is not limited to this. The signal transmitted from the DUT 2 may be input to the measurement system 100 by wire.

Next, the measurement method in the present embodiment will be described with reference to FIG. 7.

The steps other than step 9 and step 10 are the same as those in the first embodiment. In step 9, the transmission / reception unit 112 of the reception device 110 transmits the capture data string e of the processing unit L captured by the data capture unit 14 to the data processing device 120 via the communication network 130.

In step 10, the transmission / reception unit 122 of the data processing device 120 receives the capture data string e of the processing unit L transmitted from the transmission / reception unit 112 of the reception device 110.

The information of the processing unit L set by the processing unit setting unit 23 of the frame synchronization device 20 of the data processing device 120 is sent to the data capture unit 14 of the receiving device 110 via the communication network 130.

As described above, in the measurement system 100 according to the second embodiment, the time length (processing unit) of the captured data string e captured by the data capture unit 14 of the receiving device 110 is the data acquisition in the data processing device 120 and the time length (processing unit). It is the same as the data processing unit for performing the correlation calculation, and can be sufficiently shortened as compared with the conventional two frames. As a result, the amount of data transferred from the receiving device 110 to the data processing device 120 can be suppressed to the minimum amount required for frame synchronization, so that the transfer time from the receiving device 110 to the data processing device 120 can be shortened. be able to. Therefore, even when the receiving device 110 and the data processing device 120 are connected by a communication network 130 such as a LAN, frame synchronization can be efficiently performed and the measurement time can be shortened.

The frame synchronization device 20 of the first and second embodiments described above uses subframes of different frames (adjacent frames) instead of finding and synchronizing a block of one frame at the time of frame synchronization as in the conventional case. The synchronization process is performed for 10 subframes corresponding to the time length of one frame. With this configuration, for example, it is sufficient to synchronize even with a frame timing shift within 1 subframe (1 millisecond), so the capture length is about half (1 frame + 1 subframe + α) of the conventional method (2 frames + α). It is possible to reduce to. Here, α is a presample + postsample. As a result, the memory mounted on the data processing device 120 can be reduced. Further, by shortening the processing unit, the transfer time of the captured capture data string e from the receiving device 110 to the data processing device 120 can also be shortened, so that the measurement time can be shortened.

As described above, the present invention has an effect that frame synchronization can be efficiently performed and the measurement time can be shortened even when an external trigger for frame synchronization cannot be used. It is useful for all measuring devices and systems equipped with it, as well as frame synchronization methods and measuring methods.

1 Measuring device 2 DUT
10 Receiver 11 Down converter 11a RF converter 12 A / D converter 13 Orthogonal demodulation unit 14 Data capture unit 20 Frame synchronization device 21 Correlation processing unit 22 Data acquisition unit 23 Processing unit setting unit 24 Symbol length acquisition unit 25 Reference data string calculation Section 26 Reference data string storage section 27 Correlation value calculation section 28 Reference position shift section 29 Frame timing detection section 291 Threshold storage section 30 Signal processing section 31 OFDM demodulation section (demodulation section)
32 Measurement unit 40 Display unit 50 Operation unit 60 Control unit 100 Measurement system 110 Receiver 112 Transmitter / receiver unit (transmitter unit)
120 Data processing device 122 Transmitter / receiver (receiver)
130 Communication network 200 OTA chamber 201 Antenna 202 RF switch a Modulation signal b Intermediate frequency signal c Digital intermediate frequency signal d Orthogonal demodulation signal e Capture data string f OFDM demodition signal g Measurement and analysis result information h Frame timing signal r Partial data Column s Reference data column L Processing unit

Claims (12)

A frame synchronization device (20) that detects the frame timing of an input signal containing a known symbol at a specific position in the frame.
A processing unit setting unit (23) that sets the sum of one frame and the allowable amount of frame timing deviation as a data processing unit, and
A data acquisition unit (22) that acquires a data string for the set processing unit from the input signal, and
A reference data string storage unit (26) that stores at least a part of the same data string as the data string of the known symbol as a reference data string, and
A reference position shift unit (28) that determines a reference reference position in the data string acquired by the data acquisition unit and sequentially shifts the reference position at predetermined data intervals.
Each time the reference position is shifted by the reference position shift unit, the data string in the range of the same number of data as the reference data string from the reference position among the data strings acquired by the data acquisition unit, and the reference data. The correlation value calculation unit (27) that calculates the correlation value by performing the correlation calculation with the column,
A frame timing detection unit (29) that detects the frame timing based on the correlation value is provided.
The processing unit setting unit is a frame synchronization device, characterized in that a time length equal to or greater than the sum of one frame and the reference data string and less than or equal to the sum of one frame and one subframe is set as the processing unit. The frame synchronization according to claim 1, wherein the processing unit setting unit sets the minimum time length as the processing unit, which is equal to or greater than the sum of one frame and the reference data string and is an integral multiple of the slot. Device. The frame synchronization according to claim 1, wherein the processing unit setting unit sets the minimum time length as the processing unit, which is equal to or greater than the sum of one frame and the reference data string and is an integral multiple of the symbol. Device. The frame synchronization device according to claim 1, wherein the processing unit setting unit sets the time length of the sum of one frame and the reference data string as the processing unit. The processing unit setting unit is based on the frame timing detection result by the frame timing detection unit.
(A) The minimum time length of the time length equal to or greater than the sum of one frame and the reference data string and an integral multiple of the subframe.
(B) The minimum time length of the time length equal to or greater than the sum of one frame and the reference data string and an integral multiple of the slot.
(C) The minimum time length of the sum of one frame and the reference data string or more and an integral multiple of the symbol, and (D) the time length of the sum of one frame and the reference data string.
The frame synchronization apparatus according to claim 1, wherein any one of the above is set as the processing unit. The symbol length acquisition unit (24) for acquiring the symbol length information of the symbol included in the input signal is further provided, and the processing unit setting unit is based on the symbol length information acquired by the symbol length acquisition unit. The frame synchronization device according to any one of claims 2 to 5, which sets the processing unit. The frame synchronization device according to any one of claims 1 to 6, wherein the reference data string storage unit stores a part of the same data string as the data string of the known symbol as a reference data string. A receiver (10) that down-converts and samples the signal from the object to be measured and captures the data string of the processing unit.
The frame synchronization device (20) according to any one of claims 1 to 7 for acquiring the captured data string and detecting the frame timing.
A demodulation unit (31) that demodulates the signal of the captured data string based on the frame timing detected by the frame synchronization device, and
The measuring unit (32) for measuring the characteristics of the demodulated signal,
A measuring device characterized by being equipped with. A measurement system (100) including a receiving device (110) and a data processing device (120) connected to the receiving device via a communication network (130).
The receiving device is
A down converter (11) that down-converts the received signal,
The A / D conversion unit (12) that A / D-converts the down-converted signal, and
An orthogonal demodulation unit (13) that orthogonally demodulates the A / D converted signal, and
A data capture unit (14) that captures a data string of the processing unit from the orthogonal demodulated signal, and
A transmission unit (112) for transmitting the captured data string to the data processing device via the communication network is provided.
The data processing device is
A receiving unit (122) for receiving a data string transmitted from the transmitting unit of the receiving device, and a receiving unit (122).
The frame synchronization device according to any one of claims 1 to 7, which acquires the received data string and detects the frame timing.
A demodulation unit (31) that demodulates the signal of the captured data string based on the frame timing detected by the frame synchronization device, and
The measuring unit (32) for measuring the characteristics of the demodulated signal,
A measurement system. A frame synchronization method that detects the frame timing of an input signal that contains a known symbol at a specific position in the frame.
The processing unit setting step (S2) for setting the sum of one frame and the allowable amount of frame timing deviation as the data processing unit, and
A data acquisition step of acquiring a data string for the set processing unit from the input signal, and
A reference data string storage step (S3) for storing at least a part of the same data string as the data string of the known symbol as a reference data string, and
A reference position shift step (S13) in which a reference reference position is determined in the data string acquired in the data acquisition step and the reference position is sequentially shifted at a predetermined data interval.
Each time the reference position is shifted in the reference position shift step, the data string in the range of the same number of data as the reference data string from the reference position among the data strings acquired in the data acquisition step and the reference. The correlation value calculation step (S11) for calculating the correlation value by performing the correlation calculation with the data string, and
A frame timing detection step (S12, S14) for detecting the frame timing based on the correlation value is included.
A frame synchronization method, characterized in that, in the processing unit setting step, a time length that is equal to or greater than the sum of one frame and the reference data string and less than or equal to the sum of one frame and one subframe is set as the processing unit. A reception step (S4) in which the signal from the object to be measured is down-converted and sampled to capture the data string of the processing unit, and
The frame synchronization method according to claim 10, wherein the captured data string is acquired and the frame timing is detected.
A demodulation step (S15) for demodulating the signal of the data string captured in the reception step based on the frame timing detected by the frame synchronization method.
In the measurement step (S16) for measuring the characteristics of the demodulated signal,
A measurement method comprising. It is a measurement method by a measurement system (100) including a receiving device (110) and a data processing device (120) connected to the receiving device by a communication network (130).
In the receiving device
Down-convert the received signal (S5),
The down-converted signal is A / D converted (S6),
The A / D converted signal is orthogonally demodulated (S7), and then
The data string of the processing unit is captured from the orthogonal demodulated signal (S8).
The captured data string of the processing unit is transmitted to the data processing apparatus via the communication network (S9).
In the data processing device
The data string of the processing unit transmitted from the receiving device is received (S10), and the data string is received.
The frame synchronization method according to claim 10, wherein the received data string is acquired and the frame timing is detected.
Based on the frame timing detected by the frame synchronization method, the signal of the captured data string is demodulated (S15).
Measuring the characteristics of the demodulated signal (S16),
Measurement method, including that.

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