JPH06165241A - Base station equipment for time division multiplexed radio communication - Google Patents

Abstract

PURPOSE:To simplify the circuit constitution of a mobile station equipment by provid ing a transmission equalizer for equalizing transmission signals beforehand in a trans mitter and providing a means for repeatedly setting equalizing characteristics approxi mately equivalent to the equalizing characteristics of a reception equalizer. CONSTITUTION:The transmission equalizer 4 for equalizing the transmission signals beforehand is provided in a transmission part 15 and an equalization control part 43 is provided in the transmission equalizer 4 as the means for repeatedly setting the equalizing characteristics approximately equivalent to the equalizing characteristics of the reception equalizer 11 in a cycle sufficiently shorter than the fluctuation time of frequency selective fading. Then, when the distortion of the transmission line of reception burst is compensated in the equalizer of one of a transmitter-receiver and distortion compensation similar to the equalizer of a receiver is performed to transmission burst signals, the equalizer is unnecessitated in the other transmitter-receiver. That is, in a mobile communication system, when the equalizer is adopted to the transmitter and the receiver of the base station equipment, the equalizer is unnecessitated in the mobile station equipment, the mobile station equipment can be miniaturized, its power can be saved and its cost can be reduced.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention is used for digital wireless communication. In particular, it is used for a base station device in time division multiplex wireless communication. By utilizing the present invention, the mobile station device configuration can be simplified.

[0002]

2. Description of the Related Art In communications using radio wave propagation in space, the influence of a change in reception level due to fading on the transmission of information cannot be ignored. There are various causes of fading and various corresponding techniques are known, but here, the problem is frequency selective fading in which the reception level changes in a certain specific frequency region.

In frequency selective fading, a specific portion of the frequency is attenuated over time, so that the pulse signal is distorted and the digital information is erroneous.

A conventional device for this purpose will be described with reference to FIG. FIG. 5 is a block diagram of a conventional device. A conventional transmitter / receiver for time division multiplexing wireless communication has a configuration in which a reception equalizer 11 is provided on each receiver side of a base station apparatus and a mobile station apparatus in order to remove the influence of frequency selective fading.

[0005]

The adaptive equalizer for equalizing the distortion due to the frequency-selective fading that changes with time has a complicated detection circuit and a complicated control algorithm. If such an adaptive equalizer is mounted on both of the transmitters and receivers, the circuit configuration of both transmitters and receivers becomes complicated, which causes an increase in device cost. In addition, especially in the mobile communication system, in order to facilitate the carrying of the mobile station device and increase the communication time, downsizing of the transceiver,
It is necessary to reduce power consumption. The application of an equalizer for equalizing such frequency selective fading to a mobile station device hinders downsizing and power reduction.

The present invention has been made against such a background, and provides a base station apparatus for time division multiplexing wireless communication in which an equalizer is provided only in the base station apparatus and the circuit configuration of the mobile station apparatus can be simplified. The purpose is to provide.

[0007]

SUMMARY OF THE INVENTION The present invention comprises a transmitter and a receiver for transmitting and receiving burst signals in a time division manner using the same radio frequency, wherein the receiver has frequency selective fading of the received signal. It is a base station apparatus for time division multiplex wireless communication including an automatic reception equalizer that removes the influence of.

Here, a feature of the present invention is that the transmitter is provided with a transmission equalizer for equalizing a transmission signal in advance.
This transmission equalizer includes means for repeatedly setting equalization characteristics that are substantially equal to those of the reception equalizer.

It is preferable that the setting means includes means for repeatedly setting the cycle at a period sufficiently shorter than the fluctuation time of the frequency selective fading.

The transmission equalizer and the reception equalizer are digital filters, and the setting means preferably includes means for setting the coefficients of the digital filter.

[0011]

In mobile communication of time division multiplex wireless communication, opposing transceivers perform ping-pong transmission of signals at the same frequency in a time division manner. In this case, the time interval between the transmission burst signal and the reception burst signal is sufficiently shorter than the fading fluctuation time, the transmission characteristics of the transmission line of the transmission burst and the transmission line of the reception burst are equivalent at that moment, and the change is small. Is.

If the equalizer of one of the transmitters and receivers performs distortion compensation on the transmission line of the received burst and at the same time performs the same distortion compensation as that of the equalizer of the receiver on the transmitted burst signal, the transmitter and receiver of the other transmitter and receiver. No equalizer is needed. That is, in the mobile communication system, if the equalizer is applied to the transmitter and the receiver of the base station device, the mobile station device does not need the equalizer, and the mobile station device can be downsized and the power consumption can be reduced.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram of an apparatus according to an embodiment of the present invention.

The present invention comprises a transmitter 15 and a receiver 16 which transmit and receive burst signals in a time division manner using the same radio frequency, and the receiver 16 eliminates the influence of frequency selective fading of the received signal. Automatic reception equalizer 11
It is a base station apparatus for time division multiplexing wireless communication including.

Here, the feature of the present invention is that the transmission section 15 is provided with a transmission equalizer 4 for equalizing a transmission signal in advance, and the transmission equalizer 4 is equalized with the reception equalizer 11. The equalizer control unit 43 is included as a means for repeatedly setting equalization characteristics that are substantially equal to the characteristics at a cycle sufficiently shorter than the variation time of the frequency selective fading.

The transmission equalizer 4 and the reception equalizer 11 are digital filters, and more specifically, they are composed of a circuit generally called a transversal filter. The equalizer control unit 43 includes means for detecting the value of the tap coefficient, which is a weighting coefficient of the transversal filter, from the reception equalizer 11 and setting it in the transmission equalizer 4. At the time of setting the initial conditions of the base station apparatus, a training signal of a specific pattern is transmitted and received from the general station, whereby the basic constants of the filter are automatically set.

Next, the operation of the embodiment of the present invention will be described. At the reception timing of the time division ping-pong transmission of the time division multiplex wireless communication, the high frequency signal received by the antenna 8 is input to the reception unit 16 through the transmission / reception switch 9. In the reception unit 16, the received signal is converted into an intermediate frequency by the frequency conversion power amplification unit 14, separated into an in-phase component and a quadrature component by the quadrature detector 13, and analog-digital converted by the AD conversion unit 12, respectively, and then received. It is input to the equalizer 11.

The output of the reception equalizer 11 is the IQ signal synthesis unit 1.
The demodulated data sequence is combined by 0 and is output from the reception unit 16. At this time, the reception equalizer 11 receives the output of the AD conversion unit 12, extracts the influence of frequency selective fading from the signal, and equalizes it. The equalizer control unit 43 detects the tap coefficient, which is the weighting coefficient of the transversal filter at that time, and the tap coefficient is transferred to the transmission equalizer 4 of the transmission unit 15.

In the transmitting unit 15, the input data sequence is separated into the in-phase component and the quadrature component by the IQ signal separating unit 1, and converted into the baseband signal by the pulse generating unit 2 and the roll-off filter 3. The transmission equalizer 4 equalizes the baseband signal by using the tap coefficient of the equalization performed by the reception equalizer 11 and outputs the baseband signal to the DA converter 5. The baseband signal is transferred to the DA converter 5
Is converted into an analog signal and input to the quadrature modulator 6. The output of the quadrature modulator 6 is converted into a high frequency signal by the frequency conversion power amplification unit 14 and transmitted from the antenna 8 via the transmission / reception switch 9 at the transmission timing.

Next, the reception equalizer 11 will be described with reference to FIG. FIG. 2 is a block diagram of the reception equalizer 11. The in-phase component or the quadrature component of the reception signal is input from the reception equalizer input terminal 17 and sequentially input to the delay circuits 18 to 22. The outputs of the delay circuits 18 to 22 are multiplied by the contents of the tap coefficient memories 23 to 27 by the multipliers 28 to 32, and added by the adder 33. The output of the adder 33 is converted into a data sequence of an in-phase component or a quadrature component by the data determination unit 36 and output from the reception equalizer output terminal 39.
The error estimation unit 35 and the tap update unit 34 update each tap coefficient value and transfer it to the tap coefficient memories 23 to 27. Further, the updated tap coefficient value is input to the equalizer control unit 43 via the tap coefficient output terminal 40 and transferred to the transmission equalizer 4.

It has already been described that the training signal of a specific pattern is transmitted and received from the general station when the initial condition of the base station device is set, and the basic constant of the filter is automatically set by this, but the training signal is included in the received burst signal. When included, the data switch 38 is switched to the training reference signal section 37 side. When the input signal is not the training signal, the data switch 38 is switched to the data determination unit 36 side.

Next, the transmission equalizer 4 will be described with reference to FIG. FIG. 3 is a block diagram of the transmission equalizer 4. The tap coefficient value from the reception equalizer 11 is input from the tap coefficient input / output terminal 57, and each tap coefficient memory 47 is input.
Is set to ~ 51. The in-phase component or the quadrature component baseband signal from the roll-off filter 3 is input from the transmission equalizer input terminal 41 and sequentially input to the delay circuits 42 to 46. The outputs of the delay circuits 42 to 46 are multiplied by the contents of the tap coefficient memories 47 to 51 by the multipliers 52 to 56, added by the adder 58, and output from the transmission equalizer output terminal 59.

Next, the operation of the equalizer controller 43 will be described with reference to FIG. FIG. 4 is a flowchart showing the operation of the equalizer control unit 43. The equalizer control unit 43 receives the reception equalizer 1 via the tap coefficient output terminal 40 of the reception equalizer 11.
A tap coefficient of 1 is detected (S1). Further, the tap coefficient of the transmission equalizer 4 is detected via the tap coefficient input / output terminal 57 of the transmission equalizer 4 (S2). It is determined whether the tap coefficients of both the transmission equalizer 4 and the reception equalizer 11 are equal (S
3) If not equal, the value of the tap coefficient of the transmission equalizer 4 is updated with the value of the tap coefficient of the reception equalizer 11 (S4).
The above operation is repeated each time a burst signal is transmitted or received. That is, the repetition is repeated for a time sufficiently shorter than the fluctuation time of the frequency selective fading.

As described above, if the transmission signal is previously equalized by the transmission equalizer 4 using the tap coefficient determined by the reception equalizer 11, it is already equalized by the opposite receiver. The signal will be transmitted.

If this configuration is used as a base station apparatus, it is not necessary to provide an equalizer in each of the plurality of mobile station apparatuses,
The circuit configuration of the mobile station device can be simplified.

[0026]

As described above, according to the present invention, since the automatic equalizer is applied to the side of the base station apparatus, it is not necessary to provide the mobile station apparatus with an equalizer, and the size of the mobile station apparatus can be reduced. Becoming
Low power consumption and low price can be achieved.

In particular, in time-division multiplex wireless communication composed of a single base station device and a plurality of mobile station devices, the system configuration can be downsized, the power consumption can be reduced, and the price can be reduced.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of an apparatus according to an embodiment of the present invention.

FIG. 2 is a block diagram of a reception equalizer.

FIG. 3 is a block configuration diagram of a transmission equalizer.

FIG. 4 is a flowchart showing the operation of an equalizer control unit.

FIG. 5 is a block diagram of a conventional device.

[Explanation of symbols]

 1 IQ signal separation unit 2 pulse generation unit 3 roll-off filter 4 transmission equalizer 5 DA conversion unit 6 quadrature modulator 7 frequency conversion power amplification unit 8 antenna 9 transmission / reception switch 10 IQ signal synthesis unit 11 reception equalizer 12 AD conversion Part 13 Quadrature detector 14 Frequency conversion power amplification part 15 Transmission part 16 Reception part 17 Reception equalizer input terminal 18-22, 42-46 Delay circuit 23-27, 47-51 Tap coefficient memory 28-32, 52-56 Multiplier 33, 58 Adder 34 Tap update unit 35 Error estimation unit 36 Data determination unit 37 Training reference signal unit 38 Data switch 39 Reception equalizer output terminal 40 Tap coefficient output terminal 41 Transmission equalizer input terminal 42 AGC 43 Equalizer control unit 57 Tap coefficient input / output terminal 59 Transmit equalizer output terminal

Claims (3)

[Claims] 1. A transmitter and a receiver for transmitting and receiving burst signals in a time division manner using the same radio frequency, wherein the receiver automatically receives signals for eliminating the influence of frequency selective fading of received signals. In a base station apparatus for time division multiplexing wireless communication including an equalizer, the transmitter is provided with a transmission equalizer for equalizing a transmission signal in advance, and the transmission equalizer is equalized with the reception equalizer. A base station apparatus for time division multiplexing wireless communication, comprising means for repeatedly setting equalization characteristics that are substantially equal to the characteristics. 2. The base station apparatus for time division multiplex wireless communication according to claim 1, wherein said setting means includes means for repeatedly setting the cycle at a period sufficiently shorter than a variation time of the frequency selective fading. 3. The time division multiplex wireless communication according to claim 1, wherein the transmission equalizer and the reception equalizer are digital filters, and the setting means includes means for setting a coefficient of the digital filter. Base station device.