KR100270656B1 - Apparatus and method for transmitting signal in cdma mobile system - Google Patents

Abstract

A transmission apparatus of a code division multiple access communication system multiplies the channel-coded transmission signals by orthogonal modulation of the corresponding channel by the orthogonal codes of the corresponding channels, and multiplies the gain control values of the orthogonal modulation signals and the corresponding channels to obtain channel gain. A gain adjuster for adjusting the signal, a complex spreader multiplying by multiplying the channel gain-adjusted signals with the PiN sequences of the corresponding channel, and a modulator for separating and modulating the gain-adjusted transmission signal into I and Q channel signals. do.

Description

Apparatus and method for transmitting terminal of code division multiple access communication system {APPARATUS AND METHOD FOR TRANSMITTING SIGNAL IN CDMA MOBILE SYSTEM}

The present invention relates to an apparatus and method for transmitting a terminal of a code division multiple access communication system, and more particularly, to an apparatus and method for channel gain control and integer spread of a signal transmitted in binary form.

The IMT 2000 terminal, which is a next-generation code division multiple access (CDMA) transmission device, is a device capable of transmitting video data and packet data in addition to transmission of audio data. Accordingly, base stations and terminals of a next generation code division multiple access communication system include a plurality of channel transmitters and receivers.

1 is a diagram showing the configuration of a terminal transmitter of a conventional code division multiple access communication system. Referring to FIG. 1, the orthogonal modulator 111 multiplies orthogonally by multiplying orthogonal codes of channels corresponding to transmission signals of each channel. Here, the orthogonal code may use a Walsh code. A long PN code spreader 113 and a short PN code spreader 115 spread the transmission signals of the quadrature modulated channels. Here, the long code is a terminal unique identification code for identifying terminals, and the short code is a unique identification code of a base station communicating with the terminal. Baseband filter 117 filters the spread transmission signal to a baseband. The modulator 119 multiplies the baseband transmission signal by a carrier wave and outputs the transmission signal.

It can be seen that the conventional terminal transmitter having the structure as described above is implemented by a filter that spreads binary data not multiplied by a channel gain after orthogonal modulation and inputs and spreads binary data. Accordingly, as described above, a configuration for binary mapping for obtaining the binary data is required as an essential configuration as the binary data is not multiplied by the channel gain. In addition, in order to spread the obtained binary data into a long code and a short code, separate multipliers for spreading must be provided. That is, the terminal transmitter of the conventional code division multiple access communication system has a problem in that the hardware configuration becomes complicated as the configuration of a multiplier for binary mapping and spreading is required as described above.

On the other hand, the terminal transmitter of the conventional code division multiple access communication system does not disclose a separate configuration for gain adjustment, but if the gain adjustment is desired, the above-described configuration for binary mapping and a multiplier should be additionally provided. As a result, the hardware configuration becomes more complicated.

Accordingly, an object of the present invention to solve the above problems is to provide an apparatus and method for simplifying the configuration of adjusting the channel gain in a terminal of a code division multiple access communication system.

Another object of the present invention is to provide an apparatus and method for simplifying a configuration for spreading a band in a code division multiple access communication system.

Another object of the present invention is to provide an apparatus and method for performing gain compensation and spread spectrum without binary mapping in a code division multiple access communication system.

Orthogonal modulator for transmitting a coded multiple access communication system according to an embodiment of the present invention for orthogonally modulating the channel-coded transmission signals by the orthogonal codes of the corresponding channel, and each orthogonal modulation A gain adjuster for adjusting channel gain by multiplying modulation signals by a gain control value of corresponding channels, a complex spreader multiplying and spreading the PEN sequences of a channel corresponding to the channel gain adjusted signals, and the gain-adjusted transmission Characterized in that the modulator for separating and modulating the signal into I-channel and Q-channel signals.

1 is a diagram showing a configuration of a transmitter of a conventional terminal.

2 is a diagram illustrating a configuration of a transmitter of a code division multiple access communication system according to an embodiment of the present invention.

FIG. 3 is a diagram illustrating a configuration of a gain adjuster that multiplies channel gains by orthogonal modulated data in FIG.

4 is a diagram illustrating a configuration of a complex spreader that spreads input data by a short PN code spread by a long PN code in FIG.

2 is a block diagram of a terminal channel transmitter of a code division multiple access communication system according to an exemplary embodiment of the present invention. A terminal transmitter according to an embodiment of the present invention includes a pilot channel, a dedicated control channel, a supplemental channel, a fundamental channel, and the like. Here, referring to the functions of the channel transmitters of the terminal, the pilot channel is a channel for transmitting a pilot signal, the dedicated control channel is a channel for transmitting the control information of the terminal to the base station dedicated to the terminal in the link is formed, the additional channel Is a channel through which the terminal transmits packet data or video data to the base station, and a basic channel is a channel through which the terminal transmits voice information to the base station.

Referring to FIG. 2, the multiplier 212 multiplies an orthogonal code WGN1 allocated to a transmission signal of the dedicated control channel and a dedicated control channel and outputs an orthogonal spreading output. The multiplier 214 multiplies the transmission signal of the additional channel by the orthogonal code WGN2 assigned to the additional channel and outputs an orthogonal spreading signal. The multiplier 216 multiplies the transmission signal of the base channel by the orthogonal code WGN3 assigned to the base channel and outputs an orthogonal spreading output. The above configuration corresponds to a quadrature modulator configuration for orthogonally modulating the transmission signal of each channel. Here, the orthogonal code is a code assigned to distinguish each transmission channel of the terminal, and may use a Walsh code.

The gain regulator 218 adjusts the gain of the dedicated control channel by controlling the transmission signal of the orthogonal modulated dedicated control channel output from the multiplier 212 with the gain control value Gc of the corresponding channel. The gain adjuster 220 adjusts the gain of the additional channel by controlling the transmission signal of the orthogonal modulated additional channel output from the multiplier 214 with the gain control value Gs of the corresponding channel. The gain adjuster 222 adjusts the gain of the base channel by controlling the transmission signal of the orthogonal modulated base channel output from the multiplier 216 with a corresponding channel gain control value Gf. Gc is a gain control value of a dedicated control channel, Gs is a gain control value of an additional channel, and Gf is a gain control value of a basic channel. The above configuration is a channel gain controller for controlling the channel gain of each channel transmission signal output through the quadrature modulator.

The adder 224 adds and outputs the pilot channel signal and the output of the gain adjuster 218. The adder 226 adds and outputs the output of the gain adjuster 220 and the output of the gain adjuster 222.

The multiplier 228 multiplies the short PN sequence of the I channel by PNi and the long code (long PN sequence). The multiplier 230 multiplies and outputs the PN sequence PNq of the Q channel by the long code. The long code is a unique identification code assigned by the base station to distinguish each terminal, and the PN sequences PNi and PNq are base station identification codes with which the terminal communicates. Therefore, the PN sequence and the long code are codes for distinguishing terminals at the base station.

The multiplier 232 multiplies and outputs the output of the adder 224 and the output of the multiplier 228. The multiplier 234 multiplies the output of the adder 226 by the output of the multiplier 228 to spread. The multiplier 236 multiplies and outputs the output of the adder 226 and the output of the multiplier 230. The multiplier 238 multiplies and outputs the output of the adder 224 and the output of the multiplier 230. The subtractor 240 subtracts the output of the multiplier 236 from the output of the multiplier 232 and outputs the subtracted output. The adder 242 adds and outputs the output of the multiplier 234 and the output of the multiplier 238. The above configuration is a PN spreader configuration for spreading the transmission signals of each channel with the PN sequence. In other words, the configuration is a long code spreading and a PN sequence configuration, and such a structure is a complex spreader.

The band filter 244 filters the signal output from the subtractor 240 to the baseband. The band filter 246 filters the signal output from the adder 242 into the base band. Such a configuration becomes a baseband filter. The gain regulator 248 adjusts the overall gain of the I-channel transmission signal by controlling the signal output from the band filter 244 to the pilot channel gain Gp. The gain regulator 250 adjusts the overall gain of the Q-channel transmission signal by controlling the signal output from the band filter 246 to the pilot channel gain Gp. The multiplier 252 multiplies the signal output from the gain multiplier 248 with the carrier cos2 pi ft, and the multiplier 254 multiplies the signal output from the gain multiplier 250 with the carrier sin2 pi fctt. The adder 256 adds the outputs of the multipliers 252 and 254 and outputs them as a transmission signal of the terminal. Such a configuration becomes a configuration of the modulator.

Referring to the operation of the transmitter of the terminal having the structure as shown in FIG. 2, the data input for each channel is multiplied by the orthogonal code corresponding to each channel in the multipliers 212-216 and is generated as an orthogonal modulation signal of the corresponding channel. .

3 is a diagram illustrating a configuration of the gain adjusters 218, 220, and 222 according to an embodiment of the present invention.

Referring to FIG. 3, the compensator 2 ′s complement 311 converts a gain control value output from the controller into a two's complement and outputs it. The multiplexer 313 inputs a two's complement value of the gain control value output from the controller and the gain control value output from the compensator 311, and inputs an orthogonal modulation signal of the corresponding channel as a selection signal. The multiplexer 313 selects and outputs the gain control value or the two's complement value of the gain control value according to the logic of the input quadrature modulation signal. An inverter 315 inverts the quadrature modulated signal and outputs the inverted signal. Then, the output of the inverter 315 and the output of the selector 313 are combined and output. In this case, an orthogonal code output from the inverter 315 is output as a sign bit (MSB).

Referring to the operation of the gain adjusters 218-222 having the configuration as shown in FIG. 3, the multipliers 212-216 are 1-bit multipliers and perform 1-bit multiplication operations, so the multipliers 212-216 are multipliers or exclusives. It can be configured as an exclusive OR gate. The multipliers 212-216 are input to corresponding gain adjusters 218-222, respectively. At this time, the orthogonal modulated transmission signal (orthogonal modulated signal) applied to the gain regulators 218-222 becomes "1" or "0", and the orthogonal modulated signal is applied to the multiplexer 313 of the gain regulators 218-222 as a selection signal. do. In this case, the selection signal is integer data. The multiplexer 313 receiving the quadrature modulated signal as a selection signal selects and outputs a two's complement value of a channel gain control value or a channel gain control value. In this case, the channel gain control value is a value applied by the controller to adjust the gain of the corresponding channel, and the complement value of 2 of the channel gain control value is the value of 2 of the channel gain control value taken by the conservator 311. Complement value. Further, the two's complement value of the channel gain control value and the channel gain control value is a binary data value. The quadrature modulated signal is inverted by an inverter 315 and output as a sign bit. The sign bit is summed with two's complement value of a channel gain control value or a channel gain control value selectively output from the multiplexer 313 to output data. Is output. On the other hand, if the gain of the spread signal of each channel is adjusted in each gain adjuster 218-222 as described above, the signals of the gain-adjusted channels in the adders 224 and 226 are added and output in a set form.

That is, the operation performed in FIG. 3 will be described in more detail as follows. First, the orthogonal modulated transmission signal output from the Walsh modulator, that is, the multipliers 212-216, has a value of 1 (corresponding to +1) and 0 (corresponding to -1) as previously defined. Therefore, when the input of the Walsh modulator is 1 (corresponding to +1), the sign bit (output data [8]) becomes a positive value (0) by the inverter 315, and the output of the multiplexer 313 The channel gain control value is selected by the input 0 of the Walsh modulator so that the final output data [8: 0] is a channel gain control value with a positive sign bit. That is, when the Walsh modulator input is 1 (corresponding to +1), the channel gain control value may be output as it is as output data [7: 0]. On the other hand, when the output of the Walsh modulator is 0 (corresponding to -1), the sign bit (output data [8]) becomes a negative value (1) by the inverter 315, and the output of the multiplexer 313 The complementary value of 2 of the channel gain control value is selected by the input 1 of the Walsh modulator so that the final output data [8: 0] becomes the 2's complement value of the channel gain control value having a negative sign bit. That is, when the input of the Walsh modulator is 0 (corresponding to -1), the two's complement of the channel gain control value is output as output data [7: 0] to represent two's complement. As described above, FIG. 3 performs an operation of multiplying gain by the Walsh modulated data.

2 and 3 orthogonally modulates transmission data input for each channel for each channel, and the orthogonally modulated signal is multiplied by a gain control value of a corresponding channel. In this case, the gain control values Gc, Gs, and Gf applied to the gain regulators 218 to 222 are data output from a controller (not shown), and are set to values for adjusting gains of the quadrature modulation signals of the corresponding channels. As described above, the data multiplied for each channel is multiplied by data corresponding to the pilot channel and the dedicated control channel to obtain I and Q data for complex spreading, and data corresponding to the additional channel and the basic channel are added. The transmission data obtained as described above is input to the complex spreaders I and Q channels for complex spreading. The complex spread data is then applied to the band filters 244 and 246 for wave shaping, and the band filtered transmit signals are adjusted to the overall gain and then carried on the carrier.

At this time, the operation of the gain regulators 218-222 multiplying the orthogonal modulated data by the gain, the sign bit of the output data is the value inverted the binary data orthogonally modulated by the inverter 315, as shown in FIG. The orthogonally modulated signal is applied as a selection signal of the multiplexer 313. The data except for the sign bit of the output signal becomes gain data when the orthogonal modulated data is 1, and 2 of the gain when the orthogonal modulated data is 0. It becomes the reward of. In this case, the input data corresponding to the gain is 8 bits (0-255), and the output data is 9 bits. Expansion is possible even when the bit size of the input data is any bit.

4 illustrates a configuration of a complex spreader that spreads integer input data using a long code spread PN sequence according to an embodiment of the present invention.

Referring to FIG. 4, the complementer 412 complements gain and adjusts the remaining input data except for the input data [8] corresponding to the sign bit among the input data [8: 0] output through the adders 224 and 226. Takes two's complement of [7: 0] and outputs it. The multiplexer 414 receives the input data output through the adders 224 and 226 and the output of the complementer 412, and the PN sequence diffused by the long code provided through the multipliers 228 or 230 shown in FIG. PN sequence "is inputted as a selection signal. Accordingly, the multiplexer 414 selects and outputs two's complement of the input data [7: 0] or the input data [7: 0] according to the logic of the input selection signal. Exclusive NOR gate (XNOR) 416 outputs an exclusive negative OR of the spread PN sequence and the input data [8] corresponding to the sign bit. The output of the XNOR416 and the output of the multiplexer 414 are summed to output output data [8: 0], where the output of the XNOR416 is a sign bit of the output data [7: 0] output from the multiplexer 414. MSB).

The operation of FIG. 4 will now be described. Here, the input data [8: 0] is the output data [8: 0] of the adders 224 and 226, and the input data [8: 0] is the input data [8] which is the sign bit of the input data [8: 0]. Has a positive or negative value. That is, if input data [8] is 0, it is positive, and if input data [8] is 1, it is negative. On the other hand, the spread PN sequence provided through the multiplier 228 or 230 has a value of 1 (corresponding to +1) and 0 (corresponding to -1). The operation of FIG. 4 is to multiply the input data [8: 0] by the spread PN sequence 1 (corresponding to +1) or 0 (corresponding to -1). First, if the spread PN sequence is 1, +1 is equal to the input data [8: 0]. Therefore, input data [7: 0] is output as output data [7: 0]. At this time, the sign bit [8] of the output data should be output as the output data [8] which is the sign bit of the output data when the spread PN sequence is 1. Thus, output data [8] is generated by XNORing the input data [8] and the spread PN sequence. If the spreading code is 0, it is equivalent to multiplying -1 by the input data. Therefore, two's complement of the input data [7: 0] is output as the output data [7: 0]. At this time, the sign bit [8] of the output data is equal to the product of -1 when the spread PN sequence is 0. Therefore, the input data [8], which is the sign bit of the input data, is inverted and output as the output data [8], which is the sign bit of the output data. Should be. Thus, output data [8] is generated by XNORing the input data [8] and the spread PN sequence. By such an operation, FIG. 4 can spread the input data of the integer type having gain compensation by the gain regulators 218 to 222 using the PN code spread by the long code. Therefore, the sign of the output data becomes positive when the sign of the spread PNC sequence and the input data is the same, and becomes negative when the sign of the other data is different. The data excluding the sign bit of the output data are data corresponding to two's complement of the input signal excluding the sign bit when the spread PNC sequence is 0. When the spread PNC sequence is 1, the data correspond to the input signal except the sign bit. To become data. 4 illustrates an example in which an input signal is 8 bits, and may be extended to an arbitrary bit size.

Meanwhile, in the above-described embodiment, the configuration and operation are described under the assumption that the quadrature modulated signal and the spread PN sequence correspond to "+1" when "1" and "-1" when "0" corresponds. However, it is obvious that the quadrature modulated signal and the spread PN sequence may be defined by an operator. Therefore, unlike the above-described embodiment, it may be defined that the quadrature modulated signal and the spread PN sequence correspond to "-1" when "1" and "+1" when "0". In this case, the inverter 315 is not required in the configuration of FIG. 3 according to the above-described embodiment, and instead of the exclusive no-gate 416 in the configuration of FIG. 4, the exclusive oragate should be configured.

As described above, in the present invention, in performing gain compensation of orthogonal modulated data, a configuration for converting orthogonal modulated data into binary data form and multiplying the channel gain control value for gain compensation is not required. That is, the present invention has the effect of simplifying the hardware configuration by having only the configuration of selecting and outputting the channel gain control value or the two's complement value of the channel gain control value by the orthogonal modulated data. In addition, the present invention does not require a configuration of converting the spread PN sequence into binary data form and multiplying the input data even when performing spread spectrum, and selecting and outputting two's complement of the input data or the input data by the spread PN sequence. Having only has the effect of simplifying the hardware configuration.

Claims (7)

An orthogonal modulator for orthogonally modulating the channel-coded transmission signal with an orthogonal code of a corresponding channel, A generator for generating a second channel gain control value by taking a complement of the first channel gain control value corresponding to each channel; And a selector for selecting one of the first and second channel gain control values by the quadrature modulated signal. The method of claim 1, And an output unit which adds and outputs the inverted quadrature modulated signal as code bits of a channel gain control value selected by the selector. A sequence generator for generating a spreading PEN sequence for spreading the input data; A generator which takes the complement of the first input data corresponding to each channel whose channel gain is adjusted and generates the second input data; A selector for selecting any one of the first and second input data by the spread PN sequence; And a code bit generator for performing a logical operation on the code bit of the first input data and the spread PN sequence to determine the code bit of the selected input data. The apparatus of claim 3, wherein the code bit generator is an exclusive no-gate. Orthogonally modulating the channel-coded transmission signals with orthogonal codes of corresponding channels, respectively; Generating a second channel gain control value by taking a complement of the first channel gain control value corresponding to each channel; And selecting one of the first and second channel gain control values by the quadrature modulated signal. The method of claim 5, Generating a spreading PEN sequence for spreading the input data, Generating the second input data by taking the complement of the first input data corresponding to each channel whose channel gain is adjusted; Selecting one of the first and second input data by the spread PN sequence; And determining a sign bit of the selected input data by performing a logical operation on the sign bit of the first input data and the spread PN sequence. An orthogonal modulator for orthogonally modulating the channel-coded transmission signal with an orthogonal code of a corresponding channel, A multiplexer for converting a channel gain control value into two's complement, a multiplexer for selectively outputting the channel gain control value and the output of the complementary unit by the quadrature modulated signal, and the quadrature modulated signal inverted at the output of the multiplexer A gain adjuster composed of an output unit which adds bits and outputs the adjusted channel gain data; A compensator for converting the input data of each channel of which the channel gain is adjusted to two's complement, a multiplexer for selectively outputting the input data of each channel whose channel gain is adjusted and the output of the compensator by the spread P & N sequence; A code division multiple access comprising an exclusive NOR gate for generating a code bit by performing an exclusive negative OR of the spread PEN sequence and the code bit, and a spreader configured to add and output an output of the code bit and the multiplexer. Terminal transmitter of a communication system.