JP2000349679A - Composite terminal device for mobile communication - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a terminal device which can be used as a cellular or cordless radio telephone set and also can be preferentially used as an inexpensive terminal of low power consumption by supplying the power to the working one of two mobile communication systems or to only one of both systems that requires a 2nd exclusive circuit. SOLUTION: A circuit consists of a shared circuit which is shared by two mobile communication systems and the 1st and 2nd exclusive circuits which are used by only one of both mobile communication systems respectively. A power control means performs the control to supply the power to the working one of two mobile communication systems or to only one of both systems that requires the 2nd exclusive circuit. A radio receiving part 1, a radio transmitting part 2 and a control part 3 can attain the functions of both cordless and cellular radio telephone sets. The part 3 controls the supply of power to every circuit according to an operation mode that shows the function of one of both radio telephone sets.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite terminal for mobile communication, and more particularly to a composite terminal for mobile communication that can be used as either a cordless wireless telephone or a cellular wireless telephone.

[0002]

2. Description of the Related Art As a conventional mobile communication telephone device, there is a cellular mobile communication system capable of two-way communication, such as a portable telephone or a car telephone. Recently, a cordless system (PHS) service has been started. In the former cellular system, available service areas are spread almost nationwide, and high-speed mobile communication is possible. Also, the cordless system
It has the features of low call charges, low power consumption of cordless wireless telephones, and long-term non-charging use.

[0003]

The above-mentioned cellular or cordless mobile communication systems have their respective advantages and disadvantages. That is, in the cellular system, the service area is wide and can be used even in a high-speed mobile body, but the call charge is higher than a normal subscriber telephone,
In addition, there is a problem that the power consumption of the cellular wireless telephone is large, and it is not suitable for long-time carrying. On the other hand, the cordless system has the advantages that the call charge is low and the power consumption of the cordless wireless telephone is small, but has the disadvantage that the service area is narrow and cannot be used in high-speed moving objects such as vehicles.

[0004] Therefore, by subscribing to the above two systems, the advantages of both systems are utilized, that is, the call charges are as low as possible, the power consumption of the portable radio telephone device is small, and the service is provided even in a wide area and on a high-speed mobile body. It is conceivable to be able to receive it, but for this purpose, at present, it is necessary to carry both a cordless wireless telephone and a cellular wireless telephone and use them properly. At the same time, it is necessary to activate the cordless radio telephone and the cellular radio telephone and register the terminal with the base station of each system, to determine which service can be received at the current location, This does not save power.

An object of the present invention is to allow a single terminal to be used as either a cellular radio telephone or a cordless radio telephone, and to preferentially use it when it can be used as a cordless radio telephone. ,
It is an object of the present invention to provide a mobile communication composite terminal that can be used with low power consumption and low call charges as much as possible, and that can be used even in a wide service area and a high-speed mobile body.

[0006]

SUMMARY OF THE INVENTION The present invention relates to a mobile communication decoding terminal having transmission / reception functions of two different mobile communication systems, and a shared circuit used commonly for the two mobile communication systems. And a first dedicated circuit and a second dedicated circuit used in only one of the two mobile communication systems, and a circuit is configured according to which of the two mobile communication systems is being used. Alternatively, the present invention discloses a mobile communication multi-function terminal comprising a power supply control means for supplying power only to a necessary one of the second dedicated circuit and not supplying power to an unnecessary one. .

Further, the present invention discloses a mobile communication complex terminal, wherein the first system is a cordless mobile communication system and the second system is a digital cellular mobile communication system.

[0008]

Embodiments of the present invention will be described below in detail. FIG. 1 is a block diagram showing an example of the configuration of a digital mobile communication complex terminal according to the present invention, and is a digital cellular system (PDC: Personal Digital Cellular).
And a PHS (Personal Handy Phone System).

This device comprises a radio receiver 1, a radio transmitter 2,
The control unit 3 includes a control unit 3, a receiver 4, a microphone 5, a key input unit 6 for performing operations such as power on / off and mode switching, a display unit 7, a power supply unit 8, and the like. As the antenna, an internal antenna 9 and an external antenna 10 are provided. The wireless receiving unit 1 has a dual-mode compatible front-end unit 120 and a dual-mode compatible local oscillator built-in back-end unit 130, and the wireless transmitting unit 2 has a dual-mode external antenna 10 connected to a variable frequency type antenna. It has a corresponding antenna switching / matching unit 201 and a local quadrature modulator 220 with a built-in local oscillator and mixer. Further, the control unit 3 controls the analog ASIC (Application Spec
ified Integrated Circuit) 301, Digital ASI
C303, DSP (Digital Signal Processor) 30
2, CPU 304, memory 305, power control circuit 306
Etc.

The wireless receiving unit 1, the wireless transmitting unit 2, and the control unit 3 are configured to realize the functions of both the cordless wireless telephone and the cellular wireless telephone described above. The power supply to each circuit and the control of the signal path are performed in accordance with an operation mode indicating whether to operate as a cordless radio telephone or a cellular radio telephone. Here, the operation mode is determined either automatically by the control unit 3 or manually selected by the user, as described later.

[0011] The operation of the mobile communication multi-terminal having the above configuration is described in the order of the signal flow corresponding to the operation mode, the power supply control in each operation mode, and the automatic or manual setting method of the operation mode. This will be described below. First, the flow of signals during operation as a cordless wireless telephone is as follows. At this time, it is assumed that power is supplied to necessary circuits from the power supply control unit 306 in advance. In response to the control signal CONT from the control unit 3, the changeover switches (SW) 115 and 208 of the wireless receiving unit 1 and the wireless transmitting unit 2 are both in a state where their terminals a and c are connected, and Antenna switching / matching circuit (SW / MN) 10 so that external antenna 10 is used for both transmission and reception.
1 and 201 are set. The state of the antenna switching / matching circuit 201 is such that the input from the terminal b is output from the terminal a and transmitted from the external antenna 10, and the signal received by the external antenna 10 is input from the terminal a and output to the terminal d. Things. On the other hand, in the state of the antenna switching / matching circuit 101, the input from the terminal b is output to the terminal c. Thus, in the case of the cordless system, the external antenna 10 is always used for transmission and reception.

When sound is input to the microphone 5 in this state, the sound signal is output to the analog ASIC 301 and the DSP.
ADPCM (Adaptive Differential Pulse)
The signal is converted into a digital signal by a code modulation circuit. Further, conversion into two pulse trains for performing four-phase modulation (QPSK) by the MODEM function in the DSP 302 and waveform shaping of each pulse by a root Nyquist filter are performed so that the spectrum after modulation is not spread as much as possible. Pulse waveform and digital AS
The baseband signal bs at the transmission timing determined by the TDMA control circuit (time division control circuit) in the IC 303
Is input to the wireless transmission unit 2.

In the radio transmitting section 2, a quadrature modulator (QPSK) 210 modulates a four-phase signal of the local oscillation signal L _Scell output from the local oscillator 209 according to the input baseband signal bs. However, at this time, the frequency of the _local oscillation signal L _Scell is fixed. Also, this modulation is based on (π / 4) QPS
This is the K method. Further, the four-phase modulated wave is applied to the mixer 211 via the changeover switch 208, where it is up-converted by the local oscillation signal L _Scode from the local oscillator 212 and a signal having a cordless radio frequency (1.9 GHz) Band). Thereafter, the external antenna 10 is connected via the filter 207, the power amplifier 206, the filter 205 and the antenna switching / matching circuit 201.
Sent from

In the radio receiving unit 1, a received input wave from the external antenna 10 is input to the mixer 110 via the antenna switching / matching circuits 201 and 101, the filter 108, and the amplifier 109, where the local oscillator 117
_Is converted into a signal in the intermediate frequency band by the local oscillation signal L _Rcode from. The signal in the intermediate frequency band is passed through an amplification / filter circuit 111 and is then mixed by a mixer 112 with a local oscillator 11.
4 is converted into a baseband signal according to the local oscillation signal _{LIF code} from. This baseband signal is supplied to the switch 11
5, sent to the control unit 3 via the amplifier 116, where T
Processing such as separation of DMA, decoding of ADPCM, and conversion to analog signals is performed, and the speaker 4 or the display unit 7
Output to

Next, the operation of the cellular radio telephone will be described. At this time, the necessary circuits include the power supply control unit 30.
It is assumed that power is supplied in advance from No. 6. Further, according to the control signal CONT from the control unit 3, the terminals a and b of the changeover switches 115 and 208 of the wireless receiving unit 1 and the wireless transmitting unit 2 are both connected. Further, in the antenna switching / matching circuit 201, in the case of the cellular type, the input signal from the terminal c is always output to the terminal a and transmitted from the external antenna, and the reception is performed from the terminal a when the external antenna is used. Control signal C so that the input (antenna reception wave) is output to the terminal d.
Controlled by ONT. Also, the antenna switching / matching circuit 101 controls the control signal so that the input to the terminal b is output to the terminal d when the external antenna is used for reception and the input to the terminal a is output from the terminal d when the internal antenna is used. Controlled by CONT. Here, whether to use the external antenna 10 or the internal antenna 9
The control unit 3 determines while checking the reception electric field.

When a sound is input to the microphone 5 in the above state, the sound signal is transmitted to the analog ASIC 301 and the DSP.
VSELP (Vector Sum Excited Linear Pr
The digital signal is digitized by a circuit, and thereafter, this digital signal is converted into two pulse trains as in the case of the cordless system, waveform-shaped, and sent to the quadrature modulator 210 of the wireless transmission unit 2 at the timing of the TDMA control circuit. , Four-phase modulates the local oscillation signal L _Scell from the local oscillator 209.

Here, since the terminals a and b of the switch 208 are connected to each other, the output of the quadrature modulator 210 is output to the terminal b as it is, and is passed through the filter 204, the amplifier 203, and the filter 202 to switch the antenna. The signal is input to the terminal c of the matching circuit 201. Then, as described above, the signal is transmitted from the external antenna 10 according to the connection state of the antenna switching / matching circuit 201.

On the other hand, the received wave from the external antenna 10 or the internal antenna 9 is transmitted to the antenna switching / matching circuit 20.
1 and 101, the signal is input to the filter 102,
03, and the local oscillator 11
Mixed with the local oscillation signal L _Rcell from 7, it is converted into a signal of intermediate frequency band. The signal in this intermediate frequency band is amplified and
The signal is converted into a baseband signal by the mixer 106 via the filter circuit 105 by the local oscillation signal _LIFcode from the local oscillator 114. The baseband signal is sent to the control unit 3 via the changeover switch 115 and the amplifier 116, where it is subjected to processing such as separation of TDMA, decoding of VSELP, and conversion to an analog signal. Output to

Table 1 shows the frequency of the transmission / reception operation in each of the above-described systems, specifically, in the PDC system and the PHS system in Japan. In this table, “Down” and “Up” mean that

[Table 1] If it sees, it corresponds to reception and transmission, respectively. In the PDC system, a frequency band is divided into an uplink and a downlink as described above, and a plurality of lines are used in a time-division manner for each frequency channel. There are two systems, 800 MHz band and 1.5 GHz band. On the other hand, the PHS system has a configuration in which each frequency channel set in one band of the 1.9 GHz band is used in a time division manner, and transmission and reception lines are separated and used by this time division. As is clear from this table, in the PDC system, the transmission / reception (up / down) band is 130 MHz and 48 MHz in both the 800 MHz band and the 1.5 GHz band.
Hz apart, which exactly matches the intermediate frequency of each system. Accordingly, local oscillation signal L _{Rce ll} from the local oscillation signal L _Scell and local oscillator 117 from the local oscillator 209
Have the same frequency and these local oscillators can be combined into one oscillator. Note that the output frequency of the local oscillation signal L _Scell from the local oscillator 209 in the cordless mode is 940 MHz when the PDC (800 MHz) is supported.
In the case of z, PDC (1.5 GHz), the frequency is fixed at 1429 MHz.

Now, as apparent from the above description of the operation,
Each circuit in the wireless receiving unit 1, the wireless transmitting unit 2, and the control unit 3 includes one that operates in both modes of the cellular system and the cordless system, and one that operates in only one mode. Of these circuits, a circuit that operates in only one operation mode and requires power supply supplies power only during its operation and does not supply power when it is not operating, thereby reducing power consumption as a terminal. You can save money. A power supply control unit 306 provided in the control unit 3 is a circuit that performs this control, and turns on and off the current from the power supply unit 8 so that the output S0,
S1 and S2 are turned on and off. Here, the output S0 is output in both the cellular and cordless modes, and circuits operating in both modes, for example, the local oscillator 209 and the quadrature modulator 21
0, amplifier 116, CPU 304, etc. The output S1 is a circuit operating only in the cordless system, for example, the local oscillator 212, the amplifier 206,
9. Power is supplied to the ADPCM circuit and the like in the DSP 302. The output S2 is a circuit that operates only in the cellular system, for example, the amplifiers 203 and 103, the DSP 30
2 to supply power to the VSELP circuit and the like. However, as a method of dividing the power supply to these circuits, as for the method of consuming only a small amount of power, even if only one mode is operated, the power is always supplied.
Only circuits that require large power consumption, such as circuits and VSELP circuits, may be the destinations of the outputs S1 and S2. With such a configuration, it is possible to realize a terminal that has the power consumption of both modes even if it has the functions of both modes.

Next, the operation mode switching of the terminal will be described. In either case of the cellular system or the cordless system, the terminal is turned on and transmits / receives a signal to / from the base station so that the terminal can access the base station in the area where the terminal exists. Registration is performed, and a reception standby state in which a call can be sent and received at any time is established. However, when both functions are built in as in the terminal of the present invention, power consumption is wasted.

One method for solving this problem is a method in which the user determines which service area he / she is currently in, and sets an operation mode by input from the key input unit 6. Then, the control unit 3 reads this setting, and controls the power supply control unit 306 and the changeover switches 115 and 208 as described above. In this case, if the user does not know which service area the user is in, a call is first attempted as a low power consumption cordless system, and if successful, the call is started as it is.
If the cordless system cannot be used, set the cellular system.
However, in this case, for example, if the cordless system is set, a call may not be received from the other party.

Another mode setting method always attempts to register with a base station in a cordless mode. If the operation is successful, the power supply and various switches are automatically set by the control unit 3 so that the terminal operates as a cordless terminal, and a reception standby state is set. When the cordless system cannot be registered with the base station, the power supply and various switches are automatically set by the control unit 3 so as to operate as the cellular system terminal, and are registered in the corresponding base station to wait for reception. State. According to this method, when a call can be made as a cordless system, the terminal operates as the terminal, and when the cordless system cannot be used, the cellular system is automatically set only when the cordless system cannot be used. If you are in a callable area, you can talk anywhere and on a high-speed mobile, and you can always receive.

In the above description, the circuit commonly used in the two systems and the circuit used only in one system are treated separately. However, the circuits for each system are completely different in configuration and the power supply is switched. You may make it perform by the mode switching method of this invention. Further, in the embodiment of FIG. 1, the present invention has been described as a terminal covering the PDC system and the PHS system in Japan. It is clear that the invention can be applied to systems with different methods.

[0025]

According to the present invention, the system to be used is automatically or manually switched when waiting for reception, so that a low power consumption and inexpensive system can be used without confirming the service area. Calls can be made even in areas where high speed mobiles are not available. In addition, by sharing a portion that can be shared by the two systems as a terminal, an economical configuration can be achieved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration example of a mobile communication multi-function terminal according to the present invention.

[Explanation of symbols]

 Reference Signs List 1 wireless receiving unit 2 wireless transmitting unit 3 control unit 101, 201 antenna switching / matching circuit 114, 117, 209, 212 local oscillator 115, 208 local oscillation signal 104, 106, 110, 112, 211 mixer 210 quadrature modulator 301 analog ASIC 302 DSP 303 Digital ASIC 304 CPU 306 Power supply control unit

Claims (2)

[Claims] 1. A mobile communication decoding terminal having a transmission / reception function of two different mobile communication systems, a shared circuit shared by the two mobile communication systems, and the two mobile communication systems. And a first dedicated circuit and a second dedicated circuit used only in any one of the two mobile communication systems. Characterized in that it comprises a power supply control means for controlling power supply to only one of the terminals and not to supply power to unnecessary ones. 2. The mobile communication complex terminal according to claim 1, wherein the first system is a cordless mobile communication system, and the second system is a digital cellular mobile communication system. Terminal.