JPH07123065A - Time division multiplex access radio equipment - Google Patents

Abstract

PURPOSE:To reduce a transmission frame repetitive number used to converge a transmission power to a specified power by using a new correction reference resulting from correcting a correction reference in a preceding transmission frame for the transmission of a current transmission frame. CONSTITUTION:A reference value setting means 1 sends a reference value used to specify transmission power for each time slot to a high frequency transmission means 2, and the means 2 controls the transmission power outputted for each time slot based on a correction reference value formed based on the reference value. A transmission power detection means 3 detects a level corresponding to current transmission power outputted for each time slot. A correction reference control means 4 obtains a difference between the correction reference value and a detection level signal corresponding to the transmission power of a concerned time slot of a preceding transmission frame, corrects the correction reference value in a direction where a difference of the correction reference value used for the preceding transmission frame based on the difference and sends the correction reference after correction to the means 2 as a correction reference value of a time slot of the current transmission frame.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a time division multiple access radio apparatus for performing time division multiple access control.

[0002]

2. Description of the Related Art In recent mobile communications, it is required to output a constant level without being affected by the transmission output level of the apparatus, such as the environmental condition (temperature, humidity, etc.) of the apparatus, power supply voltage fluctuation and frequency. .

Further, in order to perform good mutual communication, it is necessary to set an optimum transmission output level for each time slot (hereinafter, simply referred to as a slot). The conventional technique will be described below with reference to FIGS. 5 and 6.

FIG. 5 is a diagram showing a circuit of the first conventional example and its timing. (A) shows a configuration, (B) shows a transmission or reception slot, and (C) shows a transmission period. Represents
(D) represents the distribution of transmission power.

In FIG. 5A, 31 is a modulator, 32 is an amplifier, 33 is a power amplifier, 34 is a detector, and 35 is an antenna. Reference numeral 36 is an A / D conversion (analog signal to digital signal) section, 37 is a D / D conversion (digital signal to digital signal conversion) section, 38 is a calculation section, and 39 is a D / A. It is a conversion (conversion from digital signal to analog signal) unit.

In FIG. 5B, T1, T2 to T4 (not shown) represent transmission slots, and R1 (not shown) to R4 represent reception slots. Then, T1a to T1n correspond to a time width obtained by dividing each transmission slot into clock widths.

As shown in FIG. 5A, the voice to be transmitted is modulated (eg, phase modulated) by a modulator 31 to produce modulated data, and the modulated data is amplified by a D / A converter 39 in an amplifier 32. The signal is variably amplified by the transmission control signal from and is amplified to a predetermined level.

Then, the power amplifier 33 performs frequency conversion into a specified high-frequency transmission power and amplification, and the high-frequency transmission power is radiated from the antenna 35 to the space through the detector 34.

At this time, the detection unit 34 detects a part of the high frequency transmission power to be transmitted, converts it into a digital signal in the A / D conversion unit 36, and then adds it to the calculation unit 38. On the other hand, D / D
A set value for setting the transmission power radiated from the antenna 35 to a certain value is added to the conversion section 37, and the set value is a digital format having a predetermined format in the D / D conversion section 37. After being converted into setting data, it is added to the calculation unit 38.

The arithmetic unit 38 compares the digital setting data from the D / D conversion unit 37 and the two data output from the A / D conversion unit 36 based on the clock signal to obtain a difference value between them. The difference value is added to the D / A converter 39 and converted into an analog transmission control signal.

Then, this transmission control signal is added to the amplifying section 32 so that a constant transmission power is radiated from the antenna 35. Hereinafter, the control of the high frequency transmission power will be further described with reference to FIGS. 5 (B) to 5 (D).

Transmission time of transmission slot T1 shown in FIG. 5 (B)
In the TS, the transmission power having the distribution shown in FIG. (D) is radiated from the antenna 35. Now, the transmission power corresponding to a certain transmission slot T1 is T1a, T1b ... T1n for each clock signal.
, And the transmission power in each of the divided periods T1a, T1b ... T1n is tapped by each clock signal in the calculation unit 38 to generate a transmission control signal corresponding to the transmission power, and the D / A conversion is performed. An analog transmission control signal is output from the unit 39.

Based on this transmission control signal, the amplifier 32
The degree of amplification is changed, and the power amplifier 33 corrects so that a constant transmission power can be obtained. However, in order to simplify the circuit that generates the clock signal, when the period T1a, T1b ... T1n is increased to a certain value or more, the transmission power at the beginning of transmission is the desired transmission power (indicated by the solid line). It does not become a), but becomes the actual transmission power (b) shown by the dotted line that has settled after a certain period of time TA and has a ringing state at the initial stage.

The ringing state causes the phase modulation accuracy of the amplifying section 32 to change (decrease). As described above, according to the technique of the conventional example, (1) a feedback circuit that constantly sends a certain level of transmission power without being aware of the transmission / reception slot (the circuit part 36 in FIG. 5A). ~ 39
Equivalent to) is added. (2) The transmission power level detected at the previous clock is A / D converted, and the A / D conversion is performed at the next clock.
A transmission control signal is generated from the D conversion result, and the transmission power is controlled by this transmission control signal.

FIG. 6 is a diagram showing the timing of the second conventional example. (A) shows a frame and a transmission / reception slot. For example, one transmission frame has four transmission slots T1 to T4 of multiple slots, It is shown that one reception frame is composed of four reception slots R1 to R4 corresponding to the transmission slots. In addition, (B) represents the transmission power.

In FIG. 6, when transmission is divided into multiple slots as shown in FIG.
The transmission power in the next transmission slot T2 is controlled by looking at the transmission power in T1, the transmission power in the next transmission slot T3 is controlled by looking at the transmission power in transmission slot T2, and the transmission power in transmission slot T3 is checked next. Transmit slot
The transmission power at T4 is controlled.

Therefore, when automatic transmission power control (APC) is performed, when the transmission power in the previous transmission slot is high, the transmission power in the next transmission slot is kept low, and conversely, in the previous transmission slot. When the transmission power is low, it works to increase the power in the next transmission slot.

In such a control state, when it is desired to set the transmission power to a certain desired output level in the state with APC, it is impossible to settle down to a certain predetermined value. Further, in the state with APC, the variation range of the transmission power may be larger than that in the state without APC.

[0019]

Therefore, in the technique of the conventional example, (1) in the system of the first embodiment, it takes time from the start of transmission until the output is stabilized, and the modulation accuracy is deteriorated at the start of transmission. There is a problem that this occurs (especially in the case of phase modulation).

(2) In the system of the second embodiment, when there is originally a level deviation in the transmission power between the transmission slots as in multi-slot transmission, the level deviation in the transmission power may be increased. There is a problem.

The present invention is a time division multiple access radio apparatus which stably rises in the beginning of a transmission slot, absorbs a power deviation between transmission slots caused by multi-slot transmission, and performs stable automatic transmission power control for each transmission slot. The purpose is to provide.

[0022]

In order to achieve the above object, as shown in FIG. 1, in a time division multiple access device that radiates transmission power specified for each time slot,
Reference value setting means 1 for outputting a reference value for defining the transmission power for each time slot, and high frequency transmitting means for controlling the transmission power for each time slot with a correction reference value created based on the reference value. 2, transmission output detection means 3 for detecting a level detection signal corresponding to the current transmission power output for each time slot, and the transmission output detection means 3 for detection based on the transmission power of the time slot of the previous transmission frame. The difference between the detected level signal and the correction reference value used to control the transmission power of the time slot in the previous transmission frame is calculated, and the difference value reduces the correction reference value used in the previous transmission frame. The correction reference value is corrected in the direction, and the corrected reference value after correction is output as the correction reference value for the corresponding time slot of the current transmission frame, and Configured to include a correction reference value control means 4 for holding for use in controlling the times transmission frame.

Further, the correspondence between the transmission power detected by the transmission output detecting means 3 and the magnitude of the level detection signal can be changed for each time slot based on the level setting signal output by the reference value setting means 1. To configure.

[0024]

As shown in FIG. 1, the present invention uses the new correction reference value obtained by correcting the correction reference value in the previous transmission frame in order to transmit the current transmission frame. The number of transmission frame repetitions required to converge the transmission power of each time slot to the specified value after the start can be reduced.

Since the transmission frame after once converged is always corrected to the optimum correction reference value and hardly changes, compared with the prior art in which control is performed from the beginning for each transmission frame and each time slot. It can be transmitted with the specified transmission power from the beginning of the time slot.

Further, in the second aspect of the present invention, the transmission power of each time slot can be increased or decreased by the same value with respect to the specified value by appropriately changing the detection level signal value for the same transmission power by the level setting signal. This makes it possible to remove the deviation from the specified value of the transmission power that appears in each time slot due to a temperature change or the like, by a simple operation of changing the level of the level setting signal without resetting the reference value.

[0027]

EXAMPLES Examples of the present invention will be described below with reference to FIGS. 2 and 4, the signals indicated by are signals in each circuit part.

FIG. 2 is a diagram showing a configuration of a circuit according to an embodiment of the present invention, for example, a configuration of a mobile radio apparatus. In the figure, 11 is an antenna, which radiates high-frequency transmission power to the space or receives a high-frequency signal from the space, 12 is a transmission / reception changeover switch, and in time division multiple access communication, the same frequency for transmission and reception Since the band is used, transmission / reception is switched over time.

Reference numeral 13 is a high frequency receiving section for converting a high frequency signal into an intermediate frequency signal, 14 is an intermediate frequency receiving section for converting the intermediate frequency signal into a base band signal, and 15 is a base band for modulating and demodulating voice, data and the like. It is a processing unit.

Reference numeral 16 is a voice processing / control unit 16 corresponding to the reference value setting means 1, which processes voice and sets a reference value (setting transmission power for each slot) to the microcomputer 25,
Further, a timing signal (for example, a slot switching signal) is output to each circuit in the device.

Reference numeral 17 is a first local oscillator (first local) for transmission / reception, 18 is a second local for reception, 19 is a third local for transmission, and 20 is a modulated baseband. An intermediate frequency transmitter that converts the signal into an intermediate frequency signal.

Reference numeral 21 is a high-frequency transmission section corresponding to the high-frequency transmission means 2, which converts an intermediate frequency signal into high-frequency transmission power, and 22 is a directivity for branching a part of the transmission power. It is a combiner.

Reference numeral 23 denotes a transmission output detecting section corresponding to the transmission output detecting means 3, which detects the level of the transmission power radiated from the antenna 11 and adds a detection level offset by the level setting signal to the detection level. It is to be converted into a signal. Reference numeral 24 is an A / D conversion unit for converting an analog detection level signal into digital data.

Further, reference numeral 25 denotes a microcomputer corresponding to the correction reference value control means 4, which controls each transmission power according to the correction reference value rewritten for each frame and sends out a desired transmission power for each transmission slot. It works as it is done.

That is, the microcomputer 25 is a voice processing unit / control unit.
Each reference value from 16 is stored in advance as a correction reference value of the transmission power of each slot, the correction reference value is compared with the data from the A / D converter 24 to obtain the difference, and the difference value If is greater than or equal to the specified value, the previously stored microcomputer
Make corrections to the 25 correction reference values and store again.

Then, the correction reference value for this rewriting is D
In addition to the A / A converter 26, a new transmission control signal is generated and the transmission power of the high frequency transmitter 21 is controlled by the transmission control signal.

Reference numeral 26 is a D for converting a digital signal output from the microcomputer 25 into an analog transmission control signal.
/ A conversion unit. Hereinafter, with reference to FIG. 2, the operation of transmitting / receiving voice and controlling the transmission will be described along the flow of signals.

When transmitting voice, the voice processing / control unit 16
Performs digital signal processing on voice to generate transmission data, a control signal for setting timing of each circuit, and a reference value for correction of transmission power by the microcomputer 25.

First, the transmission data is subjected to modulation and the like in the baseband processing unit 15, the intermediate frequency transmission unit 20 raises it to an intermediate frequency signal by the output of the third local 19, and the high frequency transmission unit 21 produces the first local signal 17. Is raised to a high frequency signal, and transmission power which is a high frequency signal is generated.

This transmission power is passed to the antenna 11 via the directional coupler 22 and the transmission / reception changeover switch 12,
Radiated from 11 to the space. On the other hand, in the case of voice reception, the antenna 11 receives a high frequency signal from the space, and the high frequency receiving unit 13 receives it via the transmission / reception changeover switch 12.

The received high frequency signal is supplied to the high frequency receiving unit 13
Then, it is lowered to the intermediate frequency by the output of the first local 17,
The intermediate frequency receiving unit 14 lowers the baseband signal by the output of the second local 18, and the baseband processing unit 15 applies processing such as demodulation.

The voice processing / control unit 16 performs reception processing on the data from the baseband processing unit 15 to create reception data, and receives voice. Next, transmission control of transmission power will be described. FIG. 3 is a diagram showing the data latch timing of the circuit according to the embodiment of the present invention.

In FIG. 3, (A) shows a transmission / reception frame, (B) shows data acquisition, and (C) shows details of (B). Hereinafter, FIG. 2 is also used for the description of FIG. Figure 3 (A)
As shown in (B) and (B), in order to set the correction reference value of the transmission power of each slot 1 to n of the transmission frame in advance before transmission, the reference for each slot set and output by the voice processing / control unit 16 The value is taken into the microcomputer 25 only for one transmission frame, held as a correction reference value of the transmission power during one transmission frame, and the high frequency transmission unit 21 outputs the transmission power based on the correction reference value.

At the same time, during the transmission frame period, the microcomputer 25 fetches and latches the data corresponding to the transmission power input from the A / D converter 24 for each slot 1 to n.
On the other hand, during the reception frame period, the microcomputer 25 performs audio processing /
After the reference value from the control unit 16 and the data latched from the A / D conversion unit 24, the correction reference value of the previous frame held by the microcomputer 25 is compared with the data output from the A / D conversion unit 24 for each slot. The difference is calculated, and if this difference value is greater than or equal to a predetermined value, it is recognized that the correction reference value should be changed, added to the correction reference value of the previous frame, rewritten to a new correction reference value, and then held again, The transmission power of the next frame is controlled by this new correction reference value.

Thereafter, this is repeated to converge the transmission output level of each slot to the reference value. If the level setting signal (bias of the rectifier circuit, DC amplifier circuit, etc.) applied to the transmission output detection unit 23 from the voice processing / control unit 16 is changed and the detection level signal corresponding to the transmission power is shifted, the level of the transmission power is changed. Can also be changed. In the following, description will be given with reference to FIG.

FIG. 4 is a diagram showing the configuration of the transmission output detection unit and the like of one embodiment of the present invention, and mainly describes the operation of the transmission output detection unit 23. In addition, FIG. 4 (A) shows the configuration.
4B shows the transmission power, and FIG. 4C shows the correction reference value for the slot (transmission). Symbols ~ shown in Fig. 4 are the same as symbols ~ of each circuit part shown in Fig. 2.

In FIG. 4 (A), the directional coupler 22 detects a part of the transmission power transmitted from the intermediate frequency transmitter 20 through the high frequency transmitter 21 and the directional coupler 22 to the transmission / reception changeover switch 12. Is input to the transmission output detector 23, and the capacitor C
It is rectified by the diode 23a and the diode D23a and held in the capacitor C23b as a DC level corresponding to the transmission power.

On the other hand, the level setting signal for setting the transmission level sent from the audio processing / control unit 16 to a desired value is input to the transmission output detection unit 23 and the diodes D23a, D
The voltage is divided and rectified by 23b and R23a, R23b, R23c and the like, and the result is held in the capacitor C23b.

Therefore, a voltage value Vk obtained by offsetting the DC level corresponding to the transmission output by the DC level corresponding to the level setting signal is accumulated at both ends of the capacitor C23b, and the accumulated voltage Vk is filtered by the low-pass filter 23a. It is converted into a DC voltage, which is output as a detection level signal to the A / D converter 24.

Here, if it is assumed that the transmission power converges so that the detection level signal becomes 2.5 V without changing the correction reference value in the microcomputer 25, as shown in FIG. Since the transmission output detection unit 23 has a function of controlling the high frequency transmission unit 21 by simply changing the level setting signal from the processing / control unit 16 to, for example, 1.0 V, 2.0 V, and 3.5 V, high frequency transmission The transmission power converged by the unit 21 is, for example, +23 dBm when the level setting signal is 1.0 V,
It can be changed to + 22dBm when the level setting signal is 2.0V and + 20.5dBm when the level setting signal is 3.5V.

On the other hand, the level to be converged can be changed by changing the correction reference value stored in the microcomputer 25 without changing the level setting signal.
(In this case, the transmission power can be changed for each transmission slot by changing the correction reference value even during transmission.) That is, as shown in FIG. 4 (C), for example, when the transmission output is +10 dBm. The data from the A / D converter 24 is 00
At 101, the audio processing / control unit 16 is set so that the correction reference value in the microcomputer 25 in the slot T1 is also 00101.

In this way, by changing the correction reference value in the microcomputer 25 for each transmission slot, it is possible to converge to individual transmission output for each transmission slot. In the microcomputer 25, when comparing the data based on the transmission output and the correction reference value stored in advance, if the difference is a certain value (limit value) or more, the correction reference value of the previous frame is directly corrected in the next frame. By using the reference value, it is possible to further shorten the convergence time for a temporary disturbance of the output level due to a momentary interruption or the like.

It is also possible to improve the control accuracy by taking an average value of several times of sampling when the transmission output detection unit 23 samples the transmission power and creates a detection level signal and arithmetically processing them. Is.

Generally, components such as an isolator, a switch, and an antenna connector are also used after the transmission output detector 23. The temperature characteristics of this portion are measured in advance and the temperature variable component such as a thermistor is used for transmission. By correcting the level setting signal of the output detector 23, it is possible to guarantee a precise level of transmission output.

Similarly, in the case of antenna diversity transmission, the deviation between the plurality of antennas 11 measured in advance is used for the level setting signal of the transmission output detection unit 23, and the plurality of antennas 11 are transmitted.
It is also possible to absorb the deviation by applying the correction.

[0056]

As is apparent from the above description, according to the present invention, when performing time division multiple access wireless communication,
The transmission output level can output a constant output depending on the environmental conditions (temperature, humidity, etc.) of the device, power supply voltage fluctuations, frequency characteristics, and the transmission power can be set variably for each slot, making it more efficient. The effect that it can be transmitted is produced.

[Brief description of drawings]

FIG. 1 is a diagram showing a principle configuration of the present invention.

FIG. 2 is a diagram showing a configuration of an embodiment circuit of the present invention.

FIG. 3 is a diagram showing a data latch timing of an embodiment circuit of the present invention.

FIG. 4 is a diagram showing a configuration of a transmission output detection unit and the like according to an embodiment of the present invention.

FIG. 5 is a diagram showing a circuit of a conventional first embodiment and its timing.

FIG. 6 is a diagram showing a timing of a second conventional example.

[Explanation of symbols]

 1 Reference Value Setting Means 2 High Frequency Transmitting Means 3 Transmission Output Detecting Means 4 Correction Reference Value Controlling Means

Claims (2)

[Claims] 1. A time division multiple access device that radiates transmission power defined for each time slot, a reference value setting means (1) for outputting a reference value for defining the transmission power for each time slot, and High frequency transmitting means for controlling transmission power output for each time slot with a correction reference value created based on the reference value
(2), transmission output detection means for detecting the level detection signal corresponding to the current transmission power output for each time slot (3), and the transmission output detection means based on the transmission power of the relevant time slot of the previous transmission frame. The difference between the detection level signal detected by the means (3) and the correction reference value used to control the transmission power of the time slot in the previous transmission frame is calculated, and the difference between the correction reference value used in the previous transmission frame is calculated. The correction reference value is corrected so that the difference value decreases, and the corrected reference value after correction is output as the correction reference value for the corresponding time slot of the current transmission frame and is also retained for use in controlling the next transmission frame. A time division multiple access radio apparatus comprising: a correction reference value control means (4) for 2. The correspondence relationship between the transmission power detected by the transmission output detecting means (3) and the magnitude of the level detection signal is calculated for each time slot based on the level setting signal output by the reference value setting means (1). The time division multiple access radio apparatus according to claim 1, wherein