JP3436241B2 - Redundant baseband unit in wireless communication device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for a wireless communication device and is for processing a signal from a wireless section, which is configured to include a plurality of A / D conversion circuits and a plurality of baseband signal processing circuits. It relates to a redundant baseband unit.

[0002]

2. Description of the Related Art As shown in the partial block diagram of FIG. 3, a receiver in a W-CDMA wireless communication system and other systems includes a radio unit 1 including a transmitting / receiving antenna 11 and an A connected in sequence to the output of this radio unit. The D / D conversion unit (down conversion) 2 and the baseband signal processing unit 3 are included. Illustration of other known parts is omitted.

In particular, the radio base station apparatus has a plurality of the same processing systems in order to improve reliability. Also in the apparatus shown in FIG. 3, the receiver is provided with two systems to always operate so as to have a redundant configuration.

In FIG. 3, the radio unit 1 includes a plurality of sets of antenna units 11, 11, ... And radio processing units 12, 12 ,.
The outputs of the respective groups are combined and output to the A / D conversion unit 2. The A / D conversion unit 2 is composed of a pair of A / D conversion circuits 21 and 22 (AD1, AD2) having the same configuration, and the output from the wireless unit 1 is connected in parallel to the input terminals of both A / D conversion circuits. It has been entered.

The baseband signal processing section 3 has four baseband signal processing circuits BB0, BB1, BB2, BB3,
Both A are input to the baseband signal processing circuits BB0 and BB2.
The output of the A / D conversion circuit AD0 is connected (combined), and the outputs of the A / D conversion circuit AD1 are connected to the inputs of the baseband signal processing circuits BB1 and BB3.

[0006] Then, the baseband signal processing units having different systems are connected to each other so that they can communicate with each other and communicate with each other, thereby equalizing the processing of the baseband signal processing units.

FIG. 4 shows a schematic block diagram of each baseband processing circuit 3n ' which constitutes a known baseband processing unit. In this conventional baseband signal processing circuit 3n ', received data input from the baseband signal processing unit paired by the switch element Sw; RX_BB
(RX Data from Paired BB) and received data input from the A / D converter 22; RX_AD (RX Data from A / D) is switched according to the state of the A / D state notification signal, and the received signal processor 41 input. In this way, the A / D conversion unit and the baseband signal processing circuit have a redundant configuration, and even if a part of the currently used processing system (active system) fails, the other processing system Since the processing is continued by the (standby system), the radio base station device itself does not stop.
However, this baseband processing unit simply receives the received data from the baseband signal processing unit as described above; RX_BB
And received data input from the A / D converter; RX_AD, A /
A switching Runomi according to the state of the D state signal, the basic
However , only asynchronous switching can be performed. Figure 5
(a) shows both A / D converters 21 and 22 and a pair of baseband signal processing circuits 31 and 32 when the above-mentioned respective parts are normal.
It is a connection diagram showing a connection state between the circuits. In a normal state, the signal received by the wireless unit 1 passes through the A / D conversion units 21 and 22 and is individually passed to the baseband signal processing units 31 and 32. That is, during normal operation, the A / D conversion circuit 21 (AD0)
Sends a normal A / D state notification signal to the baseband processing circuit BB0, and the baseband processing circuit BB0 processes the output of the A / D conversion circuit 21 (AD0). (See Figure 4).

In this case, the received data input (RX
Data 1-0) are not selected. In addition, the received data input (RX Data
0-1) is sent (represented by broken lines in the figure) but not used.

In exactly the same manner, the A / D conversion circuit 22 (AD1) sends an A / D state notification signal of "Normal" to the baseband processing circuit BB1, and the corresponding baseband processing circuit BB1. BB1 processes the output of the A / D conversion circuit 22 (AD1). The receive data input (RX Data 0-1) is not selected. Also, the received data input (RX Data 1-0) is sent to the paired baseband processing circuit BB0 (broken line), but it is not used. Next, the connection state between the respective parts at the time of abnormality in FIG. 5B will be described. When an abnormality occurs, the connection form at the normal time is changed to the connection form at the time of abnormality based on the above-described redundant configuration. The figure shows one A
The case where the / D conversion unit 21 (AD0) is in an abnormal state is shown. At this time, the paired baseband signal processing unit 3
It involves changing the selection of data between 1,32.

That is, in FIG. 5B, an abnormality has occurred.
In the baseband processing circuit 31 (BB1) of the baseband processing unit connected to the A / D conversion circuit 21 (AD0) of the A / D conversion unit, it is indicated that the error is output from the A / D conversion circuit 21 [ Er
[oror]] and sends / receives signals to / from the A / D converter 22 (AD1) via the baseband processing circuit 32 (BB1) connected in pairs corresponding to this signal. Continue processing by doing (asynchronous switching). If an unexpected error occurs in the A / D converter in this way, the connection status at the time of the error is immediately switched. This situation is shown in the time chart of FIG. 6 (a). However, as can be seen from FIG. 6 (a), in the case of asynchronous switching, there is a switching time lag, and data loss due to data selection change cannot be avoided.

Further, since the synchronization signal is sent only at a fixed cycle, if switching is performed regardless of the synchronization signal, the data before the establishment of the next synchronization is temporally changed. I cannot guarantee.

In a baseband signal processing-related part having a redundant configuration in a radio receiving device / equipment, in the case of switching to a standby system in response to the above-mentioned abnormal situation, data loss due to asynchronous switching Even if it is unavoidable, if the asynchronous switching is performed even at the time of returning to the normal state after repairing the faulty part or in the case of regular maintenance whose timing is known in advance, data loss and the like will still occur, which is not preferable.

[0013]

By the way, in the redundant system baseband section, data is lost in predictable path switching such as when the circuit section is replaced for maintenance or when returning to a steady state after recovery from an abnormal state. In order to avoid this, by performing synchronous switching in which the switching is performed in synchronization with the currently processed data, it is possible to avoid data loss and the like.

The time chart of FIG. 6 (b) shows the state of asynchronous switching, which is different from FIG. 6 (a).
It is known that the A / D converter is to be replaced in advance for maintenance and so on, and when it is replaced, the timing of data selection is determined according to the synchronization signal, and synchronization switching is performed. By generating the switching request at an appropriate timing immediately before the start of the next series of data processing, it is possible to eliminate the loss of data due to the selection change of the data path.

An object of the present invention is to achieve both asynchronous switching / synchronous switching when switching data paths in a redundant baseband signal processing-related portion of a radio communication device receiving section, that is, synchronous switching. It is to propose a configuration of a redundant baseband signal processing unit that can easily perform any of the above and can avoid data loss.

[0016]

In order to solve the problems, the present invention is configured to include a plurality of A / D conversion circuits and a plurality of baseband signal processing circuits used in a wireless communication device, and a signal from a wireless unit. The redundant baseband unit for processing the same is commonly used as a pair of an A / D conversion circuit to which the same output from the radio unit is input and an output of each A / D conversion circuit. A pair of baseband signal processing circuits to be input, and one set of the active system and the other set of the active system of the baseband signal processing circuit mutually exchange the input signals with each other. After being configured to output as an auxiliary input, the backup system of one set and the backup system of the other set of the baseband signal processing circuits mutually output the input signals of each other as the auxiliary input of the partner circuit. ,
In addition, each of the baseband signal processing circuits is provided with a data selection unit, and the received data input (RX_A / D) and the A / D status notification signal are also provided to the data selection unit from the A / D conversion unit. Received data input (RX_BB) is individually input from the other baseband signal processing units that are
A forced switching instruction signal forcibly instructing system switching and a synchronous switching instruction signal for instructing system switching in synchronization with the processing signal are connected, and in response to the application of the synchronous switching instruction signal or the forced switching instruction signal. Each is configured to perform asynchronous system switching or system switching synchronized with a processing signal. With such a configuration, synchronous / asynchronous switching is realized.

Further, in the data selecting section, the inside of the selecting section is provided.
Provided inIndicates whether the switch was done synchronously
A sync flag instruction signal for controlling the "sync flag"
You can connect it, and in addition, select the same in the same data selection section.
In order to switch the system synchronously inside the unit
Configuration with "switch flag" indicating that it is reserved
Also good. Even with such a configuration, switching between synchronous and asynchronous
You can do it.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, received data input from a baseband signal processing circuit paired with each baseband processing circuit forming a baseband processing unit; RX_BB
(RX Data from Paired BB) and received data input from the A / D converter; RX_A / D (RX Data from A / D) and A / D status notification signal, and also a predetermined instruction signal as input Further, a data selecting unit configured to be able to input a synchronous switching instruction signal for instructing synchronous switching is newly provided.

With this, the data selector makes it possible to achieve both asynchronous switching / synchronous switching, and in addition to performing asynchronous switching corresponding to an abnormality as in the conventional case, it is possible to freely perform synchronous switching at any time. The signal processing unit is realized.

As described above, when the A / D converter is replaced for maintenance or the like, if it is known in advance that the replacement can be performed, the timing of data selection can be determined according to the synchronization signal (synchronization switching). , See FIG. 6 (b). With this switching, it is possible to eliminate the loss of data due to the selection change of data.

Alternatively, a forced switching instruction signal for immediately and unconditionally instructing asynchronous switching may be input.

EXAMPLES The present invention will be further described below with reference to examples. FIG. 1 (a) shows a schematic block diagram of an embodiment of each of the baseband signal processing units 3n (BB0, BB1, BB2, BB3) constituting the baseband processing unit constructed according to the present invention. The baseband processing unit is the same as that shown in FIG. Also, FIG. 1B is a time chart showing a state of synchronous switching based on the circuit (FIG. 6).
Same as (b)).

Baseband signal processing circuit 3 of this embodiment
In n, a data selection unit 42 is provided, and this data selection unit 42 receives data RX_BB (received data input from a pair of baseband signal processing units (for example, baseband signal processing circuits 31 and 32 in FIG. 5)). RX Data from Paired BB)
And received data input from the A / D converter 21 (or 22);
RX A / D (RX Data from A / D) and A / D status notification signal are input.

Further, three kinds of instruction signals are input to the data selection section 42. That is, the synchronization switching instruction signal, the forced switching instruction signal, and the synchronization flag instruction signal are connected. The output of the data selection unit 42 is connected to the reception signal processing unit 41, and the selected signal is transmitted. The roles of the above three newly provided instruction signals, which are different from the conventional baseband signal processing section, are as follows. That is, the synchronization switching instruction signal S1
Is a signal for instructing switching by synchronization. The forced switching instruction signal S2 is a signal for instructing forced (asynchronous) switching just in case. The synchronization flag instruction signal S3 is a signal for controlling the “synchronization flag” provided inside the data selection unit. Further, inside the data selection unit 42, a “synchronization flag” and a “switching flag” are provided. These flags may be specially added with a circuit, but in general, they may be realized by diverting a known register, a specific address memory or the like to change the state by software.

The roles of the "synchronization flag" and the "switching flag" provided inside these data selection units are as follows.
That is, the synchronization flag F1 indicates whether or not the switching is performed synchronously, and the switching flag F2 indicates that the switching is reserved before the switching is performed synchronously. As will be described later, by using these flags, the timing of system switching is optimized and the switching between “synchronous” switching and “asynchronous” switching is performed separately.

The circuit of the above embodiment is used in the baseband processing unit of the radio communication device, and constitutes the redundant baseband processing unit of the present invention, just like the conventional redundant baseband processing circuit. That is, it is used by being connected to the A / D conversion circuit at the preceding stage, exactly as shown in FIG. 3 or FIG. FIG. 2 shows a switching operation flowchart of the data selection unit 42 in the embodiment.

The switching process starting from A is a process of switching to the standby system including a forced switching instruction and a failure check of the A / D converter. If there is a forced switching instruction (process; P
1) Correspondingly, after the flag operation, forcibly switch to the standby system operation (P4), and shift to the recovery process starting from B. A /
When the D conversion circuit fails (P5), the flag operation is performed to switch to the standby system operation, and the process also returns to the recovery process (B) (asynchronous switching). It also executes the synchronous switching to the backup system.
(P9-P12).

In the process of returning B to the active system, it is possible to return by synchronous switching by checking the instruction for the synchronization flag and setting the flag appropriately. In addition, in the instruction
More synchronous switching is possible (process; P27-P29). A / D
It is also possible to confirm that the conversion circuit has returned to normal and automatically restore it (process; P30 to P32) .

[0029]

As described above, according to the present invention, by providing the baseband processing circuit with the data selecting section and providing two kinds of internal flags, both synchronous switching and asynchronous switching can be achieved. Also, by making it possible to control the synchronization flag, it is possible to return to the original by synchronous switching after asynchronous switching, or asynchronously after switching synchronously. Become.

[Brief description of drawings]

FIG. 1A is a schematic block diagram of a baseband signal processing unit according to an embodiment of the present invention, and FIG. 1B is a time chart showing switching timing at the time of synchronous switching.

FIG. 2 is a flowchart of a switching operation of a data selection unit in the embodiment.

FIG. 3 is a partial block diagram showing a main part of a receiving device in a W-CDMA wireless communication system or the like.

FIG. 4 is a schematic block diagram showing an example of a known baseband signal processing unit.

5A and 5B are connection explanatory views showing a connection state between two A / D conversion units and a pair of baseband signal processing circuits in the device of FIG. Shows the connection state of each part when it is in the normal state and (b) shows the connection state between each part when it is abnormal.

FIG. 6A is a time chart showing switching timing at the time of asynchronous switching of the baseband signal processing circuit, and FIG. 6B is a time chart at the time of synchronous switching.

[Explanation of symbols]

1: Wireless section 2: A / D converter 3: Baseband signal processing unit 11: Antenna part 12: Wireless processing unit A / D0, A / D1: A / D conversion circuit BB0, BB1, BB2, BB3: Baseband signal processor 41: Received signal processing unit 42: Data selection section

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H04L 1/22 H03M 1/12 H04B 7/26 H04L 29/14

Claims (3)

(57) [Claims] 1. A plurality of A / s used in a wireless communication device.
A pair of redundant baseband units configured to include a D conversion circuit and a plurality of baseband signal processing circuits and for processing signals from the wireless unit, and to which the same output from the wireless unit is input. A / D conversion circuit and each A / D
The output of each conversion circuit is paired and is commonly input as a pair 2
A pair of baseband signal processing circuits, and one of the working system and the other working system of the baseband signal processing circuits outputs the mutual input signals to each other as an auxiliary input of the partner circuit. In a redundant baseband unit configured to output the input signals of one set of the backup system of the baseband signal processing circuit and the backup system of the other set to each other as an auxiliary input of a partner circuit. , A data selection unit is provided in each of the baseband signal processing circuits, and the received data is input (RX_A / D) from the A / D conversion unit to the data selection unit.
And the A / D status notification signal, and the reception data input (RX_BB) from the other paired baseband signal processing unit individually, and the compulsory switching instruction signal for compulsorily switching the system. And a synchronous switching instruction signal for instructing system switching in synchronism with the processing signal, and synchronized with the asynchronous system switching or processing signal respectively in response to the application of the synchronous switching instruction signal or the forced switching instruction signal. A redundant baseband unit configured to selectively perform system switching. 2. A synchronization flag instruction signal for controlling a "synchronization flag" which is provided in the data selection unit and which is provided inside the selection unit and indicates whether or not the switching is performed synchronously. Item 2. The redundant baseband unit according to Item 1. 3. The data selecting unit is provided with a "switching flag" inside the selecting unit to indicate that switching is reserved in advance for synchronous system switching. The redundant baseband unit according to 1 or 2.