JP2000286770A - Receiver dealing with plural carriers - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve call quality and to reduce power consumption by making the respective local oscillation part frequencies on an idle carrier side and a use carrier side to be similar and executing four-input synthesis diversity reception through the use of an idle carrier side receiver function when traffic quantity is less and an input electric field value is low. SOLUTION: A CPU part 9 designates a LOCAL part 4b with a CH designation signal in a way similar to a LOCAL part 4a. A carrier B side and an A side, which a received wave contains, are set to same LOCAL frequencies and the frequencies of the LOCAL parts 4a and 4b become same. The CPU part 9 gives an instruction for transmitting decoding data after error correction to an error correction part 7 to error correction parts 6a and 6b, makes the error correction part 7 in a standby state, error-corrects decoding data from the error correction parts 6a and 6b, corrects the errors twice, strongly corrects the errors and outputs data to a transmission path part 8 as decoding data after synthesis. Thus, a bit error rate equal to a four-input synthesis diversity reception circuit can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-carrier receiver capable of performing diversity reception.

[0002]

2. Description of the Related Art FIG. 10 is a block diagram of a conventional two-carrier transceiver. The two-carrier compatible transceiver shown in FIG. 10 uses the HYB 2a and HYB 2b for distributing the 0-system and 1-system reception waves, and the CH (channel) designation signal for A
LOCAL section 4a and LOCAL section oscillating local oscillation (hereinafter referred to as LOCAL) frequencies for system and system B reception
L unit 4b, receiving units 3a to 3d for detecting and demodulating electric fields in units of carriers, and a combining operation unit for combining demodulated signals based on electric field detection values of receiving units 3a and 3c and receiving units 3b and 3d. 5a, 5b, and the synthesis operation units 5a, 5b
Error correction units 6a and 6b for error-correcting the decoded signals of
A transmission path section 8 for multiplexing and outputting an error correction signal;
It comprises an OCAL section 4a, 4b and a CPU section 9 for controlling the error correction sections 6a, 6b.

[0003]

The conventional two-carrier transmitter / receiver described above has a configuration as shown in FIG. 10, and can be used even when one-carrier receiver operation is sufficient, such as during low traffic. There is a problem that wasteful power for two carriers is consumed.

[0004] In addition, even in the case of such low traffic, that is, in the case where there is no interference radio wave, the level schedule is the worst case, so that there is a problem that the power consumption state is high enough to withstand interference waves.

An object of the present invention is to solve the above-mentioned problems and to provide a multi-carrier compatible receiver capable of improving speech quality and reducing power consumption.

[0006]

The present invention is characterized in that a vacant carrier side of radio can perform 4-input combined diversity reception using the same LOCAL frequency as a used carrier.

Further, the present invention is characterized in that when it is no longer necessary to set a mode for performing 4-input combining diversity reception in terms of line quality, the operation can be switched to a mode for performing 2-input combining diversity reception. .

Further, the present invention is characterized in that the conversion gain of the receiving section on the operating carrier side is increased when the amount of traffic is small, there is no interference wave in the reception wave state and there is no influence of reception spurious.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a receiver for a plurality of carriers according to the present invention will be described with reference to the drawings.

FIG. 1 is a configuration diagram of a two-carrier receiver according to an embodiment of the present invention, and FIG. 2 is a configuration diagram of a combining operation unit in the receiver. The two-carrier receiver shown in FIG. 1 includes HYBs 2a and 1 for distributing a 0-system received wave.
HYB 2b for distributing the reception wave of the system, LOCAL section 4a and LOCAL section 4b for oscillating the LOCAL frequency for the A-system and B-system reception by the CH designation signal, and reception section 3a for detecting and demodulating the electric field of each carrier. ~
3d and a combining operation unit 5 for combining demodulated signals based on the electric field detection values of the receiving units 3a and 3c and the receiving units 3b and 3d.
a, 5b, error correction units 6a, 6b for respectively correcting the decoded signals of the combining operation units 5a, 5b, and error correction units 6a, 6b.
6b, an error correction unit 7 for further correcting the error correction signal from the switching unit 19b, a transmission line unit 8 which receives an upper-level signal from the switching unit 19, multiplexes and outputs the error correction signal, and a switching unit 19
And a CPU section 9 for controlling the LOCAL sections 4a and 4b and the error correction sections 6a, 6b and 7 in response to the higher-level signal from the CPU.

As shown in FIG. 2, a combining operation section 5a and a combining operation section 5b in the receiver include decoding sections 16a and 16 for detecting a received signal from the receiving section for electric field and converting I and Q signals.
b and weighting calculation units 17a and 17b for converting the electric field detection value and weighting the I and Q signals in accordance with the electric field detection value
And a vector synthesizing unit 18 for synthesizing the weighted signals of the arithmetic units 17a and 17b.

In the following, the access method of the present invention
DMA (time division multipl)
e access: time division multiple access)-FD
D (frequency division dupl)
ex: Frequency division duplex) An embodiment of a configuration applied to a half-rate digital mobile communication system adopting the system will be described in detail with reference to the drawings.

FIG. 3 is a configuration diagram of the radio base station apparatus.
FIG. 4A is a 0-system IF vector diagram, and FIG.
FIG. 4C is a vector diagram of the combination calculation units 5a and 5b, and FIG.
FIGS. 6A and 6B are RSSI characteristic diagrams of FIGS.
FIG. 7 is a spectrum diagram of the mode reception signal and the LOCAL signal, FIG. 7 is a BER characteristic diagram of the reception units 3a to 3d, and FIG. 8 is a reception unit 3 according to an embodiment of the present invention.
It is a block diagram of the receiver for 2 carriers which controls a and 3c.

The receiver of the present invention is generally used for applications such as the radio base station apparatus 10 shown in FIG. The radio base station apparatus 10 includes a transmitting / receiving antenna 11 for transmitting and receiving system 0, a receiving antenna 12 for receiving system 1 only, and a combining / distributing unit for combining and distributing a transmission wave and a system 0 receiving wave to the radios 15a to 15n. 13 and the 1-system reception waves to the radios 15a to 15
and a distribution unit 14 for distributing the data to a plurality of mobile terminals using wireless devices 15a to 15n.

At this time, the switching apparatus controls the radio base station apparatus 10 and transmits frequency information and information of transmission / reception data as upper signals.

First, a description will be given of ordinary two-input combining diversity compatible with two carriers. Radio 15a-
15n is compatible with two carriers, and thus has two transmitters and four receivers (reception units 3a to 3d). Accordingly, in one radio, in the half rate mode, 6 TCHs per carrier and TCHs (tr
Afficient channel (information channel) can be processed simultaneously. When processing 7 TCH or more, the second carrier is used.

The receivers in the radios 15a to 15n receive the carrier A (f1) corresponding to the two carriers in order to receive the weighted combining diversity after the detection of the two branches for the two carriers. , 3c, a combining operation unit 5a, an error correcting unit 6a, and a LOCAL unit 4a. On the other hand, for receiving carrier B (f2), receiving units 3b and 3d, a combining operation unit 5b, an error correcting unit 6b, and a LOC
An AL unit 4b is provided.

In the simultaneous reception operation, the LOCAL section 4a (FA) is used with a CH designation signal corresponding to each carrier so that the reception waves of the carrier A and the carrier B can be received in advance.
= F1 + IF) and LOCAL section 4b (FB = f2 +
IF) (FIG. 6 (a)).

Here, a plurality of received waves (radio waves including carrier A and carrier B) from the mobile terminal are input to system 0 and system 1, and the received wave of system 0 is divided into two by HYB 2a, The received wave of the system is divided into two by the HYB 2b.

The received waves of a total of four systems are set to 0 at the receiving unit 3a.
The carrier is converted into the RSSI signal and demodulated data of the carrier A of the system, the carrier B of the system 0 at the receiving unit 3b, the carrier A of the system 1 at the receiving unit 3c, and the carrier B of the system 1 at the receiving unit 3d. The RSSI information and the phase information are represented by vectors as shown in FIGS. 4A and 4B.

The receiving units 3a and 3c of the output carrier A
In the combining operation unit 5a, the combining operation is performed by adding the weight corresponding to the demodulated data to the demodulated data (FIG. 4C).

The combining operation unit 5a includes a weighting unit 17a
And the vector synthesizing unit 18 has a LIN square table and a COS θ table of the RSSI signal, and calculates r 2 power and COS θ from each RAM using the RSSI 0/1 and IF 0/1 as addresses.

Accordingly, as shown in FIG. 5, since the RSSI signal of IF0 is higher than that of IF1, the phase information has a specific gravity such that the demodulated data of system 0 is more important than the demodulated data of system 1 as phase information. It becomes a calculation.

The weighted demodulated data of the carrier A is converted by an error correction unit 6a using a Viterbi algorithm into
The bit error rate of the demodulated data affected by the fading is improved and supplied to the transmission path unit 8.

Similarly, the carrier B side also includes the receiving units 3b and 3d.
After combining the RSSI signal and the demodulated data with the demodulated data by adding a weight corresponding to the demodulated data to the demodulated data in the synthesizing operation unit 5b, the demodulated data is subjected to a bit error rate correction by an error correction unit 6b using a Viterbi algorithm. Improve
It is supplied to the transmission path unit 8.

The error-corrected decoded data of the carriers A and B input to the transmission line unit 8 are multiplexed in the transmission line unit 8 and transmitted to the switching device 19 via the transmission line.

Next, the operation of the 4-input combining diversity will be described. The 4-input combining diversity is, for example, 6
This is applied when the traffic amount is as low as one carrier corresponding to TCH and the input electric field value is as small as 30 dBμV or less.

Here, in a reception situation where the traffic volume is small and it is not necessary to use the receiver function on the carrier B side, the receiving units 3b and 3d, the combining operation unit 5b, and the error correction unit 6b need to be operated. However, since it is not known when it is needed, the current in the standby state is always consumed.

Therefore, the flow of the operation for performing the signal processing on the carrier A side by using the B side reception block is as follows.

First, the CPU unit 9 performs the same designation as the LOCAL unit 4a with respect to the LOCAL unit 4b by a CH designation signal.

Therefore, the carrier B side is set to the same LOCAL frequency as the carrier A side. LOCAL part 4a
(FA = f1 + IF) and LOCAL part 4b (FA = f1
+ IF) has the same frequency (FIG. 6B). At the same time C
The PU unit 9 issues an instruction to the error correction units 6a and 6b to transmit the decoded data after the error correction to the error correction unit 7. Further, the error correction unit 7 is set in a standby state, and further decodes and combines the decoded data from the error correction units 6a and 6b so that the decoded data can be output to the transmission path unit 8 as decoded data.

The flow of the received wave is inputted from the system 0 and the system 1, the system 0 is divided into two by the HYB 2a, and the system 1 is divided into two by the HYB 2b. The received waves of the total 4 systems are
Four RSs of 0/1 carrier in receivers 3a to 3d
An SI signal and demodulated data are generated, and the combined operation unit 5a,
The decoded data that has passed through 5b and the error correction units 6a and 6b are respectively processed and then input to the error correction unit 7, where the error correction is performed twice, and a strong error correction process is performed.

By operating as described above, an improvement in bit error rate (BER) equivalent to that of the four-input combining diversity receiving circuit can be obtained. However, the processing time in the error correction unit 7 must be performed within a time that does not affect the call processing.

On the other hand, when the input electric field value is as high as 30 dBμV as shown in FIG. 7 during the reception mode of the 4-input combining diversity, the bit error rate becomes 1 × 10 ⁻⁶ or less even with the 2-input combining diversity. Since there is no problem in the line quality, there is no need to set the receiving mode to the 4-input combining diversity mode. The operation mode is switched to the 2-input combining receiving mode, and the receiving sections 3b and 3d, the combining operation section 5b, and the error correcting section are performed. 6b, the power of the error correction unit 7 is turned off, and low power consumption operation can be performed.

Next, another embodiment of the present invention will be described. FIG. 8 is a configuration diagram of a two-carrier receiver that controls the receiving units 3a and 3c.

In the traffic environment as described above, that is, when one carrier is sufficient for the used frequency, there is no other frequency in the same zone, and there is no influence of reception spurious. Therefore, in such an environment, when the input electric field is as low as −2 dBμV or the like, the conversion amplification degree of the receiving units 3 a and 3 c on the used carrier side is increased,
A trade-off between sensitivity and spurious is made from the level diagram of the receiver.
It is also possible to apply an offset as if the input was higher than the actual RSSI signal, to make the bit error rate (BER) characteristics look good, and to improve the line quality.

As an example of this operation, the CPU 9
The same designation is performed for the CAL unit 4b, the error correction units 6a and 6b, and the error correction unit 7. Furthermore, a command is also sent to the receiving units 3a and 3c to increase the conversion gain of the receiving unit alone.

[0038] Thus consuming receiver 3a, 3c bit error rate (BER) characteristics in the conversion gain of rose min only offset with respect to the conventional 0dBμV input ^10-2 bit error rate (Fig. 7 the solid line), A bit error rate of 10 ^-2 can be obtained with ^-2 dBμV input (broken line in FIG. 7).

The flow of the received wave is the same as that of the above-described embodiment, but the specific gravity of the error correction units 6a and 6b is such that an offset is applied to the actual input electric field to improve the bit error rate. Since the decoded data of the error correction unit 6a is processed by applying a specific gravity, the bit error rate can be improved.

However, since this operation is different from the actual input level from the mobile terminal, when performing call processing using the RSSI signal, it is necessary to perform processing by subtracting the RSSI signal by an offset. There is.

In this case, the receiving unit conversion amplification of the receiving unit on the used carrier side is increased, and if there is no problem in the line quality, the operation is switched to the receiving mode of the two-input combining diversity, and the receiving units 3b, 3d, The power of the combining operation unit 5b, the error correction unit 6b, and the error correction unit 7 is turned off, and low power consumption operation can be performed.

Although the embodiments of the present invention have been described with respect to a receiver supporting two carriers, the number of receivers is not limited as long as call processing with a mobile terminal can be performed.

The front end of the receiving unit and the LO
By making the CAL section wider, it is possible to process mobile terminals in different frequency bands in the same system.

On the other hand, during one-carrier operation in a low traffic state, as shown in FIG. 9, HYBs 20a and 20b are mounted between the LOCAL unit 4a and the receiving units 3a and 3d, respectively, and the LOCAL unit 4b and the receiving unit are mounted. There is also a configuration example in which SWs (switches) 21a and 21b are mounted between the switches 3b and 3c, respectively.

This is because SW 21 is in the two-carrier operation state.
a, 21b are conducted to the B terminal, and the LOCAL portions 4a, 4b
b, but 1 in the low traffic state
In the case of carrier operation, the CPU unit 9 switches SW21.
By issuing an instruction to switch from terminal B to terminal A to terminals a and 21b, LOCAL unit 4a results in receiving unit 3
a, 3b, 3c, 3d.

At this time, the CPU 9 sends the LOCAL 4
By issuing a stop instruction to b, the power consumption of the LOCAL unit 4b can be reduced.

[0047]

As described above, the multicarrier receiver according to the present invention can be used at low traffic.
The same LOCA as the used carrier is also used on the wireless free carrier side
By setting the frequency to the L frequency, it is possible to perform 4-input combining diversity reception, which has the effect of contributing to the improvement of speech quality.

Further, at this time, there is an effect that the conversion gain of the receiving unit is increased, which contributes to the improvement of the communication quality.

Further, when there is no problem in the call quality,
With the two-input combining diversity, the power of the receiving units 3b and 3d, the combining operation unit 5b, the error correction unit 6b, and the error correction unit 7 is turned off, which has the effect of reducing power consumption.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a two-carrier compatible receiver according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a combining operation unit in the receiver.

FIG. 3 is a configuration diagram of a wireless base station device.

FIG. 4 is a 0-system IF vector diagram, a 1-system IF vector diagram, and a vector diagram of a combining operation unit.

FIG. 5 is an RSSI characteristic diagram of the receiving units 3a to 3d.

FIG. 6 is a spectrum diagram of a 2 and 4 mode reception signal and a LOCAL signal.

FIG. 7 is a BER characteristic diagram of the receiving units 3a to 3d.

FIG. 8 is a configuration diagram showing another embodiment of the present invention.

FIG. 9 is a configuration diagram illustrating an example in which a switch is provided during operation of one carrier in a low traffic state and operation is performed using only one LOCAL frequency.

FIG. 10 is a configuration diagram of a conventional two-carrier transceiver.

[Explanation of symbols]

 2a, 2b HYB 3a, 3b, 3c, 3d Receiving unit 4a, 4b LOCAL unit 5a, 5b Combining operation unit 6a, 6b, 7 Error correcting unit 8 Transmission path unit 9 CPU unit 10 Wireless base station apparatus 11 Transmitting and receiving antenna 12 Receiving antenna DESCRIPTION OF SYMBOLS 13 Combination distribution part 14 Distribution part 15a-15n Radio 16a, 16b Decoding part 17a, 17b Weighting calculation part 18 Vector synthesis part 19 Switching device

Claims (7)

[Claims] When the traffic volume is small and the input electric field value is low, the frequency of the local oscillator on the free carrier side of the radio is made the same as the frequency of the local oscillator on the used carrier, and the receiver function on the free carrier side is used. A multi-carrier receiver capable of performing 4-input combining diversity reception using the same. 2. The multi-carrier receiver according to claim 1, wherein the conversion gain of the receiving section on the used carrier side is increased when the traffic amount is small and the input electric field value is low. 3. In a receiving state in which it is not necessary to use the receiver function on the idle carrier side due to line quality, 2
3. The receiver according to claim 1, wherein the operation can be switched to an operation for performing input combining diversity reception. 4. The multi-carrier receiver according to claim 1, wherein the receiver is used for a half-rate digital mobile communication system employing a TDMA-FDD system. 5. When the traffic volume is small and the input electric field value is low, the frequency of the local oscillator on the free carrier side of the radio is made the same as the frequency of the local oscillator on the used carrier side, and the receiver function on the free carrier side is used. A diversity receiving method for a multi-carrier receiver, wherein four-input combined diversity reception can be performed using the method. 6. The diversity receiving method for a multi-carrier receiver according to claim 5, wherein the conversion gain of the receiving section on the used carrier side is increased when the traffic amount is small and the input electric field value is low. 7. In a reception state in which it is not necessary to use the receiver function on the free carrier side due to line quality, 2
7. The diversity receiving method for a multi-carrier receiver according to claim 5, wherein the operation can be switched to an operation for performing input combining diversity reception.