JP2001326623A - Cdma base station receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a CDMA base station receiver that replaces a wrong base band signal output with a signal generated by a relay section, when the wrong base band signal is generated due to the fault of a reception section so as to prevent processing by wrong data. SOLUTION: The receiver consists of a reception section 10, a relay section 20 and a base band processing section 30. The base band signal, generated by the reception section 10, is fed to a selector section 22 via an input data conversion section 21 of the relay section 20. When receiving a wrong base band signal, the selector section 22 selects and outputs consecutive '0s' data generated by the relay section 20. The base band processing section 30 takes a correlation value between the received data and a normal base band signal, to detect the fault in the base band signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CDMA base station receiver provided with a circuit for preventing output of an erroneous baseband signal suitable for use in a CDMA mobile communication system.

[0002]

2. Description of the Related Art FIG. 5 is a block diagram of a conventional base station receiver in a mobile communication system using the CDMA system. The receiving unit 10 converts the frequency of the radio signal received via the antenna 40, and performs A / D (analog / digital) conversion to generate a time-division multiplexed baseband signal. The relay unit 50 selects a signal of a sector designated for each baseband processing unit 60 from the baseband signal before despreading generated by the receiving unit 10, and
0. As shown in FIG. 6, the relay unit 50 includes a data processing unit 1 ・ 521 and a data processing unit 2 ・ 522,
It processes baseband signals received via antennas 1 and 2 used for diversity reception.

When a normal baseband signal is not input from the receiving unit 10 to the data processing unit 1/521 or the data processing unit 2/522, the outputs of the data processing unit 1/521 and the data processing unit 2/522 are different. , Two different baseband signals are supplied to the baseband processing unit 60. In this case, the baseband processing unit 60 recognizes that the baseband signal is abnormal by detecting the correlation value between the two baseband signals, and controls the signal processing.

[0004]

However, according to the conventional method described above, when an error occurs in the baseband signal received via the antenna 1 or the antenna 2,
Since an error in the baseband signal was recognized from the correlation value between the two signals, an erroneous baseband signal is output and processed during the time from detection of the error to the corresponding time.
There is a problem that the accuracy of signal processing is reduced.

[0005] The present invention has been made in view of the above points, and an object of the present invention is to convert a baseband signal into a continuous "0" signal when an erroneous baseband signal is generated due to a failure of a receiving unit or the like. It is an object of the present invention to provide a CDMA base station receiving apparatus having a circuit that is fixed and prevents an erroneous baseband signal from being transferred to a baseband processing unit.

[0006]

According to an aspect of the present invention, there is provided a receiving unit for receiving a radio signal and generating a baseband signal, and a signal input from the receiving unit. A relay unit for selecting a signal of a predetermined sector from the baseband signal and performing format conversion; and a baseband processing unit for performing despreading of the output of the relay unit and performing symbol demodulation processing. A signal generating means for generating a signal of a predetermined pattern, and when an error occurs in the baseband signal generated by the receiving unit,
Data selection means for switching the baseband signal to an output signal of the signal generation means and outputting the output signal.

[0007] The invention described in claim 2 is the first invention.
In the CDMA base station receiving apparatus described in the above, the data selecting means, when an erroneous baseband signal is generated due to a failure of the receiving unit or the like, output data based on a control signal supplied from the receiving unit. It is characterized by selecting.

[0008] The invention described in claim 3 is the first invention.
In the CDMA base station receiving apparatus described in (1), the signal of the predetermined pattern generated by the signal generating means is a continuous "0" signal.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration of the CDMA base station receiving apparatus of the embodiment. The same elements as those of the conventional receiver shown in FIG. 5 are denoted by the same reference numerals, and description thereof will be omitted. In FIG. 1, 2
Reference numeral 0 denotes a relay unit including an input data conversion unit 21, a selector unit 22, a data processing unit 23, and an output data conversion unit 24.

[0010] The input data converter 21 performs serial / parallel conversion of the baseband signal input to the relay unit 20 before despreading. The selector unit 22 selects and outputs a baseband signal input from the input data conversion unit 21 or a continuous “0” signal generated by the selector unit 22 based on the selection signal supplied from the reception unit 10. The data processing unit 23 separates the input time-division multiplexed data, selects a signal of a sector specified for each baseband processing unit 30, and performs data time-division multiplexing. The output data converter 24 performs parallel / serial conversion and format conversion of the input baseband signal. The baseband processing unit 30 performs despreading and symbol demodulation processing of the baseband signal input from the relay unit 20, and outputs a decoded signal.

In digital mobile communication, a sector cell system in which a plurality of sectors are formed using a directional antenna is used in order to increase the efficiency of radio frequency use. Here, as shown in Table 1, it is assumed that the base station adopts a configuration of six sectors, and each sector is provided with two antennas used for diversity reception. Therefore, the receiving unit 10
Generates six baseband signals.

[0012]

[Table 1]

FIG. 2 is a diagram showing the selector section 22 in more detail. As shown in FIG.
It has a selector section 1,221 to a selector section 6,226. The six baseband signals input from the input data conversion unit 21 are supplied one by one to the selector units 1.221 to 6.226. FIG.
For example, the data received by antennas 0, 7
An example is shown in which data supplied to the selectors 1 and 221 and received by the antennas 1 and 6 are supplied to the selectors 2 and 222.

FIG. 3 is a block diagram of the selector section 1, 22 shown in FIG.
1 is a circuit diagram showing a specific configuration of a selector unit 1 and selector units 2 and 222. The selector sections 1 and 221 are switching circuits including AND gates (logical AND circuits) 101a and 102a and an OR gate (logical OR circuit) 103a. The data received via the antenna 0 is input to the AND gate 101a, and the continuous “0” data generated in the selector unit 22 is supplied to the AND gate 102a. Then, based on the selection signal a generated by the reception unit 10, the reception data or the continuous “0” data is selected and output from the OR gate 103a. The circuit configuration of the selector units 3.223 to 6.226 is the same as the configuration shown in FIG.

The operation of the CDMA base station receiving apparatus according to the present embodiment will be described below with reference to FIG. 2 and FIG. First, antennas 0 to 11 provided in six sectors are provided.
The radio signal received via the
/ D conversion to generate six baseband signals. These six baseband signals supplied to the relay unit 20 are serially / parallel converted by the input data conversion unit 21, respectively, and converted into a data format that can be processed inside the relay unit 20. Then, the signals are supplied to the selector units 1,221 to 6,226 one by one.

The operation of the selector units 1 and 221 will be described below. Note that the same processing is performed for the selector units 2.222 to 6.226. A baseband signal input from the input data conversion unit 21, for example, a baseband signal received via the antenna 0 is input to one terminal of the AND gate 101a.
The other terminal is supplied with a selection signal a from the receiving unit 10. On the other hand, the selector unit 22 generates continuous “0” data and supplies it to one terminal of the AND gate 102a. The selection signal a is supplied to the other terminal.

When the receiving unit 10 is generating a normal baseband signal, the selection signal a causes the AND gate 10
The baseband signal input to 1a is selected, and is output from the OR gate 103a to the data processing units 1 and 231.
The data processing units 1 and 231 separate the input time-division multiplexed data, select a signal of a predetermined sector, and perform time-division multiplexing of the data. Similar processing is performed for baseband signals of other systems, and data processing units 23 to 6
A system baseband signal is output. The output data conversion unit 24 performs parallel / serial conversion and format conversion on the six baseband signals input from the data processing unit 23, and outputs three baseband signals from the six baseband signals. The baseband processing unit 30 performs despreading of the baseband signal supplied from the relay unit 20, performs symbol demodulation processing,
The data is demodulated and output.

On the other hand, when an erroneous baseband signal is generated due to a failure of the receiving unit 10 or the like, the receiving unit 10 outputs a selection signal a based on the error information. The selection signal a is supplied to the AND gate 101 of the selector unit 221.
a, 102a. AND by selection signal a
Continuous “0” data supplied to the gate 102a is selected, and the data processing unit 1 ·
231 is output. The data subjected to the above processing in the data processing units 1 and 231 and the output data conversion unit 24 is supplied to the baseband processing unit 30. The baseband processing unit 30 detects an abnormality of the baseband signal by calculating a correlation value between the input continuous “0” data and a normal baseband signal, and performs a process corresponding to a failure of the receiving unit 10. Perform

The selector section 22 of the relay section 20 may be provided in accordance with the number of baseband signal systems input from the receiving section 10. FIG. 4 is a block diagram illustrating a configuration of a receiving apparatus in a case where N selectors 22 are provided according to N baseband signals. N-system selector unit 2
Providing 2 makes it possible to deal with processing of N baseband signals or other signals requiring control.

[0020]

As described above, according to the present invention,
When an error occurs in the baseband signal due to a failure of the receiving unit or the like, data processing using an erroneous baseband signal can be prevented by switching to continuous “0” data and performing processing. Of the mobile communication system can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration of a relay unit.

FIG. 3 is a circuit diagram illustrating a configuration of a selector unit.

FIG. 4 is a block diagram showing another embodiment.

FIG. 5 is a block diagram illustrating a configuration of a conventional receiving device.

FIG. 6 is a block diagram illustrating a configuration of a data processing unit.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Receiving part 20, 50 relay part 21 Input data conversion part 22 Selector part 23 Data processing part 24 Output data conversion part 30 Baseband processing part 40 Antenna 101a, 102a, 201a, 202a AND gate 103a, 203a OR gate 221-226 selector Units 1 to 6 231 and 232 Data processing units 1 and 2

Claims (3)

[Claims] A receiving unit that receives a radio signal and generates a baseband signal; a relay unit that selects a signal of a predetermined sector from the baseband signal input from the receiving unit and performs format conversion; A baseband processing unit that performs a symbol demodulation process by despreading an output of the relay unit, wherein the relay unit includes a signal generation unit configured to generate a signal of a predetermined pattern, and a base unit generated by the reception unit. Data receiving means for switching the baseband signal to an output signal of the signal generating means and outputting the signal when an error occurs in the band signal. 2. The data selection means according to claim 1, wherein, when an erroneous baseband signal is generated due to a failure of said receiving section, data to be output is selected based on a control signal supplied from said receiving section. The CDMA base station receiving apparatus according to claim 1, wherein 3. The CDMA base station receiving apparatus according to claim 1, wherein the signal of the predetermined pattern generated by the signal generating means is a continuous “0” signal.