JP3062175B1 - Transmission output control circuit and mobile communication device using the same - Google Patents

Abstract

Abstract: A mobile communication device that simultaneously transmits a plurality of transmission waves having different frequencies from the same antenna can greatly reduce power consumption and can reduce the size of a transmission circuit, and a device using the transmission circuit. To provide. A circuit for modulating a carrier signal with a plurality of different signal waves and transmitting the modulated signal, the circuit comprising:
It is characterized by having directional couplers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a transmission output control circuit capable of simultaneously transmitting a plurality of different transmission waves.

[0002]

2. Description of the Related Art Conventionally, in communication equipment such as mobile communication which simultaneously transmits a plurality of different signal waves from the same antenna, as shown in FIG. 3 , a rated power for transmitting a plurality of signal waves is maintained. For this reason, the transmission output cannot be detected and fed back simultaneously. For this reason, conventionally, a transmission system as shown in FIG. 3 is provided for each oscillator. That is, such a transmission system includes, for example, the oscillator 1
A variable attenuator 2, a multiplier 4 for multiplying a carrier wave from the transmitting local oscillator 8 by a frequency signal from the oscillator 1,
An amplifier 5 for amplifying a multiplied signal obtained from the carrier and the frequency signal multiplied by the multiplier, and a directional coupler 6 for carrying the multiplied signal amplified by the amplifier 5 to an antenna are connected to the oscillator 1, It had to be provided for each 1 '.
These transmission systems need the same number as the number of oscillators. And, as described above, in the transmission system, a detection circuit that feeds back a high frequency detected from a directional coupler for performing detection for keeping power transmitted in the transmission system constant, It was provided in the transmission system.

[0003] Therefore, in such a transmitter,
It is necessary to provide a transmission system for each oscillator, and considerable power is required during transmission. Further, since the conventional transmitter has the above-described detection circuit, it is an obstacle in reducing the size of the transmitter.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has as its object to provide a transmission circuit capable of greatly reducing power consumption and reducing the size of a device. It is an object. In particular, such a transmission circuit can be applied to mobile communication devices such as mobile phones.

[0005]

A transmission output according to claim 1 is provided.
The force control circuit changes the carrier signal with a plurality of different signal waves.
A circuit for adjusting and transmitting the modulated signal.
A carrier signal is modulated by a plurality of signal waves and transmitted.
Circuit for the directional coupler from the directional coupler
Extract a part of the signal of the transmitted wave and branch the extracted signal
A branch portion, a carrier wave and a signal wave branched by the branch portion;
A multiplier for multiplying the multiplied wave by the signal wave;
A detector for detecting the signals from the detectors, and a detection signal from the detector.
Signal to detect the power and the power of the circuit is approximately rated
Detection means having a holding portion for holding the
Sign.

According to a second aspect of the present invention, there is provided a transmission output control circuit.
2. The method according to claim 1, wherein the detector is limited to an intermediate frequency band.
It is characterized in that it is a possible intermediate frequency filter.

[0007] A mobile communication device according to a third aspect is a mobile communication device.
A transmission output control circuit according to item 1 or 2.

According to the present invention, in a mobile communication device for simultaneously transmitting a plurality of transmission waves of different frequencies from the same antenna, a plurality of transmission waves can be detected by one transmission wave detection circuit at the same time. A plurality of more stable transmission waves can be transmitted, thereby reducing power consumption and miniaturizing the device.

In the transmission output control circuit according to the present invention, as shown in FIG. 1, the signal waves of different frequencies f ₁ and f ₂ oscillated by the oscillator 1 and the oscillator 1 ′ are
, A plurality of waves are synthesized and multiplied by the frequency L ₀ oscillated from the transmitting local oscillator 8 by the multiplier 4, for example, the radio frequency (transmission frequency), (L ₀ + f ₁ , L ₀₎
+ F ₂ ), is further amplified to a specified transmission power by the power amplifier 5, is transmitted from the antenna 7 after passing through the directional coupler 6, and is preferably configured. At this time, a plurality of transmission powers obtained from the directional coupler 6 are distributed by the distributor 9 and then multiplied by the multipliers 10 and 10 'by the oscillators 1 and 1' which are the local oscillation frequencies. , Band-pass filters 11 and 11 'can obtain power values of different frequencies, respectively. The obtained power values can be converted into DC voltages by detection diodes 12 and 12', respectively. Control (hereinafter AP)
C) by the APC processing units 13 and 13 ′, and by applying DC voltages corresponding to the respective frequencies by the variable attenuators 2 and 2 ′ that can control the attenuation of the high-frequency power by the DC voltage, The specified transmission power is transmitted so as to reach the rated power.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of such a transmission output control circuit according to the present invention will be described below. FIG. 1 shows a configuration example according to the first embodiment of the present invention. Here, a case where two oscillators are used will be described. As described in a second embodiment described later, in the present invention, the number of oscillators used in the present circuit is not limited to two, and may be three or more. Not restricted.

The configuration according to the first embodiment of the present invention comprises oscillators 1 and 1 'which oscillate two different frequencies,
Variable attenuator 2, which can vary high-frequency power input from oscillators 1, 1 'to an output level corresponding to a specified transmission output
2 ′, a combiner 3 for combining two different frequencies output from the variable attenuators 2 and 2 ′, and a high frequency output from the combiner 3 and a high frequency oscillated from the local oscillator 8 for transmission. A multiplier 4 for multiplying, a power amplifier 5 for amplifying the high-frequency power output from the multiplier 4 to a specified transmission output, and a directional coupler 6 for detecting the power output from the power amplifier 5
And the antenna 7 for transmitting the prescribed transmission output constitutes a transmission unit.

The detector includes a divider 9 for dividing the high-frequency power detected by the directional coupler 6 into two, and a frequency output from the divider 9 to each of the oscillators 1 and 2.
1 ′, and multipliers 10 and 10 ′, and multipliers 10 and 1
An intermediate frequency filter 11, 11 'for limiting the band to two high frequencies output from 0', a detection diode 12, 12 'for converting the filtered intermediate frequency into a DC voltage, and a detection diode 12, 12'. APC processing unit 1 for outputting a DC voltage corresponding to a specified transmission output at each frequency to variable attenuators 2, 2 'according to the output DC voltage.
3, 13 '.

The operation of the first embodiment will be described in detail with reference to FIG.
Different frequencies (f ₁ , f ₁ ) oscillated by the oscillators 1 and 1 ′
_{In 2} ), the attenuation can be controlled by a DC voltage, and after passing through the variable attenuators 2 and 2 ′ that transmit an output level corresponding to the specified antenna transmission power, they are combined by the combiner 3.

The signal combined by the combiner 3 is combined with the carrier frequency (L ₀ ) oscillated from the transmitting local oscillator 8 by the multiplier 4 and multiplied by a high frequency to obtain two different radio frequencies. A signal (transmission signal) of (f ₁ + L ₀ , f ₂ + L ₀ ) is generated. The generated radio frequency signal is
Each power is amplified by the power amplifier 5 to the specified antenna transmission power, and after passing through the directional coupler 6, is transmitted from the antenna 7.

The radio frequencies (f ₁ + L ₀ , f ₂ + L ₀ ) obtained from the directional coupler 6 are distributed by the distributor 9 and the oscillators 1 and 1 ′, which are the respective original oscillations. Are multiplied by the signals (signal wave signals) of the respective frequencies (f ₁ , f ₂ ) transmitted by the multipliers 10 and 10 ′, and the intermediate frequencies (f ₁ + L ₀ −f ₁ = L ₀ , f ₂ + L ₀₎ −f ₂ =
L ₀ : carrier frequency).

When the obtained intermediate frequency signal is input to intermediate frequency bandpass filters 11 and 11 'to limit the band, only a desired wave (L ₀ : carrier signal) is extracted.
The extracted desired wave (carrier) is transmitted to the detection diode 1
2, 12 'to convert the power of the desired wave (L ₀ ) into a DC voltage, and then input the desired wave converted into a DC voltage so that APC processing is performed by the APC processing units 13 and 13'. . This is subjected to an APC process so as to transmit a stable transmission power at each frequency to a DC voltage corresponding to each purpose corresponding to the specified antenna transmission power, and then fed back to the variable attenuators 2, 2 '. Note APC processing unit, the signal strength is provided in order to hold the oscillation power of the circuit constant, for example, (f ₁ + L ₀₎ was introduced by the power amplifier device (f ₁ + from the signal intensity of the L _0), the difference in signal strength is fed back to the distributor front (f ₁ + L _0), basically obtained by measuring the oscillation power. In the present invention, to determine such signal strength,
The rated power of the transmission output control circuit according to the present invention is maintained using a simply determined value for measuring the intensity of the input signal of the APC processing unit.

That is, the APC processing unit measures the intensity of the desired wave converted into the input DC voltage, and compares the measured value with data stored in a storage unit provided in the APC. As a result, the feedback signal is fed back to the variable attenuator so that the rated power in the circuit is constant. When a signal (transmitted wave signal), for example, (f ₁ + L ₀ ) or the like is attenuated by the distributor or the like, the signal can be appropriately amplified using an amplifier. The information such as the amplification factor can be stored in the APC processor. This makes it possible to apply optimized feedback to the variable attenuator. Also, the method of combining and distributing transmission waves by these combiners and distributors is merely an example, and it goes without saying that other known methods may be used.

Next, a second embodiment of the present invention will be described. In the above-described first embodiment of the present invention, the case where the number of oscillators (signal waves) is two has been described.
In the second embodiment, the number of the signal waves is not limited. In the present embodiment, the detection unit (multiplier 10, intermediate frequency bandpass filter 11, detection diode 1
2. By increasing the number of APC processing units 13), for example, theoretically, an infinite number of transmission waves (modulated signal waves by carrier signal waves) can be output.

FIG. 2 shows a transmission output control circuit when the number of signal waves (oscillators) is three. In FIG. 2 , when the number of signal waves is n = 3, the combiners 3, 3 ',.
The number of ^(n-2) ′ is 2, and the distributors 9, 9 ′,.
・ The same applies to the number of 9 ^(n-2) '. Here, n represents a natural number of 2 or more. That is, in this example, the number of combiners and distributors is given by n−1, where n is the number of signal waves. However, the number of combiners and distributors is merely an example. The distributor may combine three or more signal waves at one time, and similarly, the distributor may be configured to distribute at one time. When the signal is attenuated by the distributor, the attenuated signal can be appropriately amplified in the same manner as described in the section of the first embodiment. This makes it possible to apply optimized feedback to the variable attenuators 2, 2 ′... 2 ⁽ⁿ⁻²⁾ ′, as in the first embodiment. The method of combining and distributing transmission waves or signal waves by these combiners and distributors is merely an example, and other known methods may be used.

[0020]

According to the present invention, the power consumption can be significantly reduced by the transmission output control circuit according to the present invention. The reason is that since one transmission system can output a plurality of transmission waves, it is only necessary to have one power amplifier that can supply most of the current during transmission.

Further, the transmission output control circuit according to the present invention can contribute to downsizing of the device. The reason is that only one transmission system is required, so that only one large power amplifier or the like is required. Therefore, the communication device having the transmission output control circuit according to the present invention can significantly reduce power consumption and can be downsized. By using such a transmission output control circuit, it is possible to provide a small-sized mobile communication capable of multiple transmission output / input.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a configuration of a first embodiment of a transmission output control circuit according to the present invention.

FIG. 2 shows a second embodiment of the transmission output control circuit according to the present invention;
FIG. 2 is a circuit diagram showing a configuration of the embodiment.

FIG. 3 is a diagram showing a conventional circuit.

[Explanation of symbols]

 Reference Signs List 1 oscillator 1 'oscillator 2 variable attenuator 2' variable attenuator 3 combiner 4 multiplier 5 power amplifier 6 directional coupler 7 antenna 8 transmitting local oscillator 9 distributor 10 multiplier 10 'multiplier 11 intermediate frequency filtering Unit 11 'Intermediate frequency filter 12 Detection diode 12' Detection diode 13 APC processing unit 13 'APC processing unit

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-64-48524 (JP, A) JP-A-3-265314 (JP, A) JP-A-6-132835 (JP, A) JP-A 8- 274734 (JP, A) JP-A-61-163729 (JP, A) JP-A-53-103628 (JP, U) JP-B-47-48004 (JP, B2) ⁷ , DB name) H04B 1/04 H04J 1/00

Claims (3)

(57) [Claims] 1. A circuit for modulating a carrier signal with a plurality of different signal waves and transmitting the modulated signal, wherein the circuit extracts a part of a signal of a transmitted wave from a directional coupler and extracts the extracted signal. A multiplying unit that multiplies the signal wave by a multiplication wave of the carrier wave and the signal wave branched by the branching unit; a detection unit that detects a signal from the multiplication unit; and A transmission output control circuit, comprising: a detection unit having a holding unit that receives the detection signal, detects the power, detects the power, and holds the power of the circuit at a substantially rated value. 2. The apparatus according to claim 1, wherein said detection unit is an intermediate frequency filter capable of limiting an intermediate frequency band.
3. The transmission output control circuit according to 1. 3. A mobile communication device having the transmission output control circuit according to claim 1.