JP2973258B2 - Analog / digital shared transmission power automatic controller - Google Patents

Abstract

PURPOSE:To obtain the automatic transmitting power controller of an analog/ digital shared system which operates an exact and stable control. CONSTITUTION:A sample/hold circuit 7 whose operation is switched by a control signal is inserted between a detector circuit 3 and an integration circuit 4, and a comparator 10 to compare the secondary signal of a coupler 8 provided between a modulator 11 and a mixer 12 through a detector circuit 9 with a reference voltage (f) is provided and the sample/hold circuit 7 is controlled by the output signal of a comparator 10. Then, at the time of an analog system operation, the reference voltage (f) is set so that a sample operation can be continuously performed. and at the time of a digital system operation, the sample operation is performed only when a burst signal is turned ON, and a hold operation is performed when the burst signal is turned OFF. Thus, a control voltage (c) is constant, and a transmitting output signal level can be stable and exact.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mobile telephone (cellular).
APC (Automatic Power Control) for both analog and digital systems
It is about.

[0002]

2. Description of the Related Art An analog car telephone system according to the prior art is provided with frequency division multiple access (FDMA).
Division Multiple Access). 5 to 7 show a conventional automatic transmission power control device (AP).
It is a block diagram which shows the example of a structure 1-3 of the structure C). As shown, the input signal (burst control signal) is applied to the modulator 1
The signal is modulated by 1 and combined with the output signal of the local oscillator 13 by the mixer 12 and input to the power amplifier 1. In the configuration examples 2 and 3, the signal is input to the power amplifier 1 through the voltage control attenuator 6. Further, the signal is output as a radio wave from the antenna 14 through the coupler 2 (directional coupler) from the power amplifier 1.

The secondary output signal of the coupler 2 is supplied to a detection circuit 3,
The integration circuit 4 inputs the voltage according to the transmission output level to the differential amplifier 5. This voltage is compared with the reference voltage, and the difference voltage is amplified by the differential amplifier 5 and is provided as a control voltage c to the gain control terminal of the power amplifier 1 in the configuration example 1 of FIG.
In the configuration example 2 of FIG. 6 and the configuration example 3 of FIG.
Is fed back through the control terminal of With the control voltage c, the transmission output signal level d is automatically controlled so as to be constant according to the reference voltage.

[0004] On the other hand, digital car telephone systems are based on time division multiple access (TDMA).
cess) Burst transmission by the method is performed. Therefore, in the case of the TDMA operation in the digital car telephone system having the structure shown in FIGS. 5 to 7, the burst control signal b 'is turned off.
In the F state, the control voltage c is applied to the power amplifier 1 or the voltage control attenuator 6 so that the transmission output signal d has the maximum output.

[0005]

However, in the transmission power automatic control device having the above-mentioned conventional configuration, when the burst control signal b 'is inputted as shown in FIG. 8, the burst control signal b' is turned off. When the control voltage c is changed to the ON state due to the time constant of the integrating circuit 4 or the response delay of the loop,
Has a waveform as shown in the figure, and the transmission output signal level d becomes unstable at each rising edge of the burst signal, and an accurate AP
There is a problem that the C operation is not performed.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide an analog / digital shared transmission power automatic control device capable of eliminating the above problems and performing accurate and stable control. Aim.

[0007]

In order to solve the above-mentioned problems, the present invention provides a sample-and-hold device whose operation is switched between a detection circuit 3 and an integration circuit 4 by a control signal as shown in FIG.
And a comparator for comparing a secondary signal of a coupler 8 provided between the modulator 11 and the mixer 12 with a reference voltage f through a detection circuit 9. A means for controlling the hold circuit 7 so as to perform a continuous sampling operation when the analog system is operated, to perform a sampling operation only when the burst signal is ON when the digital system is operated, and to provide a hold operation when the burst signal is OFF is provided. It is characterized by having.

[0008]

According to the present invention, the control signal b of the sample and hold circuit 7 causes the sample operation to be performed continuously during the analog operation and the sample operation to be performed only when the burst signal is ON during the digital operation. , The reference voltage f is set so as to perform a hold operation. Therefore, the control voltage c is constant as shown in FIG. 4 unlike the conventional case, and the transmission output signal level is stable and accurate.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a diagram showing a configuration example of the automatic transmission power control device of the present invention. As shown in the figure, this device
Amplifier 1, coupler (directional coupler) 2, detection circuit 3,
Integration circuit 4, differential amplifier 5, sample & hold circuit 7, coupler (directional coupler) 8, detection circuit 9, comparator 10, modulator 11, mixer 12, local oscillator 13
And an antenna 14.

As shown in the figure, analog and digital input signals are modulated by a modulator 11, and an output signal is combined with an output signal of a local oscillator 13 by a mixer 12 through a coupler 8 and input to the power amplifier 1. . Further, the signal is output as a radio wave from the antenna 14 through the coupler 2 from the power amplifier 1.

The secondary output signal of the coupler 2 is supplied to a detection circuit 3,
The sample and hold circuit 7 and the integration circuit 4 input the voltage according to the transmission output level to the differential amplifier 5.
This voltage is compared with the reference voltage e, and the difference voltage is amplified by the differential amplifier 5 and fed back to the gain control terminal of the power amplifier 1 as a control voltage c. With the control voltage c, the transmission output signal level d is automatically controlled so as to be constant according to the reference voltage.

FIG. 3 is a timing chart of signals of various parts in the analog system by the present apparatus. In the analog system, since the FDMA system is used, a continuous transmission state is established during a call. Accordingly, the output of the detection circuit 9 for detecting the modulated signal obtained by the coupler 8 is as shown in FIG. Only when the reference voltage f of the comparator 10 is being transmitted is the comparator.
Set the data output to high level. The sample and hold circuit 7 is controlled by the comparator output signal b. When the comparator output signal b is at the high level, the sample & hold circuit 7 is in the sample state, and when it is at the low level, it is in the hold state. Therefore, at the time of a telephone call in the analog system, the transmission output automatic control is always performed in the sample state at exactly the same operation timing as the analog system of the mobile telephone system.

FIG. 4 is a timing chart of various signals in the digital system by the present apparatus. The comparator output is set to a high level only when the reference voltage f of the comparator 10 is in the transmission state (burst signal ON state).
Therefore, in the digital system, the sample & hold circuit 7 performs the sampling operation when the burst signal is ON, and performs the hold operation when the burst signal is OFF.
That is, a voltage value corresponding to the transmission level is sampled while the TDMA transmitter is in the ON state, and this voltage value is held while the TDMA transmitter is in the OFF state. The comparison with the reference voltage e is performed. Therefore, the transmission output level when the burst signal is ON can be controlled to be constant without being affected by the transmission output level when the burst signal is OFF.

That is, since the control voltage c shown in FIG. 4 is constant irrespective of the state of the burst signal, it does not become unstable even when each burst signal rises, and the burst signal is ON.
In the state, since a feedback operation, which is a normal APC operation, is being performed, an accurate APC operation is also performed.

FIG. 2 is a diagram showing another configuration example 2 of the automatic transmission power control device of the present invention. The difference between the automatic transmission power control device of FIG. 2 and the automatic transmission power control device of FIG. Insert the attenuator 6 between the mixer 12 and the power amplifier 6,
The other configuration and operation are substantially the same as those of the automatic transmission power control device of FIG. 1 in that the control voltage c from the differential amplifier 5 is input to the control terminal of the voltage controlled attenuator 6.

[0016]

As described above, according to the present invention, the following effects can be expected. Sample &
By providing a hold circuit and switching control signals, it is possible to easily cope with a shared system. In addition, the response of the APC at the time of the burst rise during the digital operation can be performed stably and accurately.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration example of a transmission power automatic control device according to the present invention.

FIG. 2 is another configuration example 2 of the automatic transmission power control device of the present invention.
FIG.

FIG. 3 is a timing chart of signals of various parts in the analog system by the present apparatus.

FIG. 4 is a timing chart of signals of respective parts in a digital system by the present apparatus.

FIG. 5 is a block diagram illustrating a configuration example of a conventional automatic transmission power control device.

FIG. 6 is a block diagram showing another configuration example 2 of the conventional automatic transmission power control device.

FIG. 7 is a block diagram showing another configuration example 3 of the conventional automatic transmission power control device.

FIG. 8 is a timing chart of signals of various parts of the conventional automatic transmission power control device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Power amplifier 2 Coupler (directional coupler) 3 Detection circuit 4 Integrator circuit 5 Differential amplifier 6 Voltage control attenuator 7 Sample & hold circuit 8 Coupler (directional coupler) 9 Detection circuit 10 Comparator 11 Modulator 12 Mixer 13 Local oscillator 14 Antenna

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁶ identification code FI H04B 7/26 V (58) Field surveyed (Int.Cl. ⁶ , DB name) H04B 7/24-7/26 102 H04Q 7 / 00-7/38 H03G 3/30 H04B 1/04

Claims (1)

(57) [Claims] 1. A device comprising a modulating means and an amplification adjusting means, comprising means for extracting a transmission output signal and feeding back a difference voltage from a first reference voltage to the amplification adjusting means to stabilize an output signal level. An analog / digital shared transmission power automatic control apparatus, comprising: comparison means for comparing the output signal level of the modulation means with a second reference voltage; and sample and hold means whose operation is switched by a control signal. By inserting the sample & hold means into the feedback circuit and controlling the sample & hold means with the output signal of the comparing means, the sample operation is performed continuously during the analog operation. In the digital mode operation, the sampling operation is performed only when the digital signal is ON, and the holding operation is performed when the digital signal is OFF, so that the transmission output signal level is stable and accurate. Automatic transmission power control unit of the analog / digital common method which is characterized in that a means for controlling.