JPH08140147A - Digital cordless telephone terminal - Google Patents

Abstract

PURPOSE: To provide the digital cordless telephone terminal with which a high- definition audio signal can be transmitted by providing plural audio signal encoding/decoding means inside the telephone set of a slave station and detecting the idle state of time slots. CONSTITUTION: A signal processing part 3 is provided with a MODEM circuit and a channel CODEC part or the like. A speech CODEC part 4 is composed of two kinds of audio encoding/decoding means. A detecting part 6 detects the idle state of time slots to be used for a radio circuit part 2. A selecting part 7 selects any one CODEC at the speech CODEC part 4 corresponding to the result of the detecting part 6. The slave station detects the idle state of time slots through a base station while using the detecting part 6 inside the telephone set. Since time slots #2, #3, #6 and #7 are used and transmission/ reception is enabled, the slave station designates the time slot by using a time slot designating part 9 inside the telephone set together. High-definition transmission is enabled by the selection of the speech CODEC part 4 at the selecting part 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital cordless telephone terminal for transmitting high quality voice.

[0002]

2. Description of the Related Art Conventional digital cordless telephone terminals,
For example, personal handy phone (hereinafter referred to as PHS)
In the case of 32k-ADPC,
M is the basic specification.

Therefore, inside the telephone, analog data of voice is converted from analog to digital, and these data are converted into 32 kb by an adaptive differential quantization (ADPCM) circuit.
Convert to ps data and send out.

[0004]

However, in the above-mentioned conventional example, although it is strong against noise due to the digital radio depending on the form of use, in consideration of various usage conditions, high-quality voice is produced as much as possible. In addition to the current band of 0 to 4000 Hz, high-quality transmission such as 7 kHz audio band transmission means is required.

Therefore, an object of the present invention is to provide a digital cordless telephone terminal capable of high-quality transmission of voice in different bands.

[0006]

According to the present invention, a large amount of voice data can be transferred by using a plurality of slots at the same time for time division duplex / time division (TDMA / TDD). When a time slot in which data can be transferred can be secured, by having a plurality of voice encoding / decoding means inside the telephone, by selecting one of the plurality of voice encoding / decoding means, It realizes high-quality transmission using a plurality of time slots.

[0007]

1 is a block diagram showing the configuration of a mobile telephone (hereinafter referred to as a slave station) used in the first embodiment of the present invention.

The antenna 1 transmits and receives radio waves to and from the master station, and the radio circuit section 2 has a frequency synthesizer, an IF, a transmission / reception amplifier, etc. necessary for transmission / reception at a radio frequency. The signal processing unit 3 has a modulation / demodulation circuit (π / 4 shift QPSK or the like in PHS) and a channel codec unit.

The speech codec section 4 is shown in FIG.
It is composed of two types of speech encoding / decoding means (hereinafter referred to as codec). The control unit 5 is composed of a microcomputer, RAM, ROM, etc. that controls the entire slave unit.

The detection unit 6 is a TDMA / T of the radio circuit unit 2.
The selection unit 7 detects the empty slot state of the time slot used in the DD, and the selection unit 7 selects one of the codecs of the speech codec unit 4 based on the detection result of the detection unit 6. The operation unit 8 has a display unit such as a display unit and a key input unit including various input keys.

The time slot designating section 9 designates a time slot to be used based on the detection result of the detecting section 6, and the speaker 10 and the microphone 11 carry out transmission / reception and the like.

FIG. 2 is a block diagram showing the coding units of the two types of codecs in the speech codec unit 4.

These have already been standardized by the standard standards JT-G721 and JT-G722.

The audio signal 21 input from the microphone 10 is input to the transmission audio section 22 and the sampling circuit 33.

The transmission audio section 22 inputs the audio signal 21 and outputs a signal 23 sampled at a uniform 14 bits and 16 kHz. The transmission quadrature mirror filter 24 is
Sampling signal 23 is input, 8 kHz sampling output 25 in the low range (0 to 4000 Hz) and high range (4000 to 8000 Hz).
8 kHz sampling output 26 of the (Hz). Then, the output 25 is quantized into 6 bits by the low band ADPCM encoder 27 and becomes a 48 kbps signal 28. Also,
The output 26 is quantized into 2 bits by the high band ADPCM encoder 29 and becomes a 16 kbps signal 30.

These signals 28 and 30 are multiplexed into a multiplexer 31.
Is output as data 32 of 64 kbps and is input to the selection unit 7.

The audio signal 21 is output as a PCM signal of 64 kbps by the sampling circuit 33, and AD
Converted to a 32 kbps signal by the PCM encoder 34,
It becomes the output signal 35. This signal 35 is also input to the selecting section 7 in the same manner.

Next, in the system as shown in FIG. 3, the case where the slave station (a) 45 in the A zone and the slave station (b) 46 in the B zone communicate with each other will be described.

First, both slave stations 45 and 46 perform call connection control in the main unit 41 via the base stations 42 and 43. Therefore, the usage state of the time slot in transmission is as shown in FIG. 4, and a certain frequency is transmitted in a time division manner.

Here, one cycle is composed of 8 time slots with a period of 5 ms. Therefore, transfer of approximately 32 kbps is possible in one time slot.

For example, when the time slot # 1 in FIG. 4 is used for transmission from the slave station 46, the other party (slave station 45)
Sends back the received data at the timing of time slot # 5. Transmission and reception are performed between the slave station (a) 45 in the A zone and the slave station (b) 46 in the B zone of FIG. 3 using such a transmission means.

In this case, it is assumed that at the time of call setup, transmission and reception are performed using the time slots # 2 and # 6 shown in FIG. However, when the slave station b in the B zone moves to the C zone, the base station is changed from 43 to 44, so that the call setup needs to be redone between the slave stations 45 and 46.

At this time, the slave stations 45 and 46 are connected to the base station 42,
The empty state of the time slot is detected by the detection unit 6 inside the telephone via 44. At this time, if the time slots can be continuously secured in both the A zone and the C zone as shown in FIG.
Select Also, time slots # 2, # 3, # 6,
Since it becomes possible to perform transmission / reception using # 7, both the slave stations 45 and 46 specify the time slot in the time slot specifying unit 9 inside the telephone.

Therefore, the selection unit 7 is used to select 64 kbps and 7 kHz of the speech codec unit 4, and it becomes possible to transmit a high-quality audio signal for voice transmission.

Next, a second embodiment of the present invention will be described. The configurations shown in FIGS. 1 and 2 are common to the present embodiment.

Next, in the system as shown in FIG. 7, the slave station (a) 56 in the A zone, the slave station (b) 57 in the B zone, and the slave station (c) 58 in the C zone communicate with each other. The case of performing will be described.

First, the slave station (a) 56 in the A zone has only one type of normal 32 kbps codec, and it communicates with the slave station (b) 57 in the B zone via the base stations 53 and 54. Further, transmission / reception is performed via the public network 52 and the main device 51 on the B zone and C zone side. At this time as well, transmission / reception is performed in time slots # 2 and # 6 shown in FIG.

However, once the slave station (b) 57 in the B zone is used.
Puts a call to the other station (a) 56 on hold and puts a call from the other station (a) 56 to the other station (c) 58 in the C zone via the base station 55. c) When handing over to 58, the detecting unit 6 of the slave station detects an empty slot state with the main device 51 in both the B zone and the C zone.

Also in this case, when a call is set up for transmission / reception, and empty time slots can be continuously secured, two time slots are used at a time as shown in FIG. Slots # 2, # 3, # 6,
Send and receive at # 7.

FIG. 8 is a block diagram showing the configuration of a slave station used in the third embodiment of the present invention.

As shown, in this embodiment, the first
In addition to the configuration of the embodiment (FIG. 1), a request unit 12 is provided. The request unit 12 monitors the signal of the speech codec unit 4 and clocks a silent state in both directions for a certain period of time, and outputs a request for using a plurality of time slots when there is no sound for a predetermined period of time. To do.

The configuration of the speech codec section 4 is as follows.
It is assumed that it is common with the first embodiment (FIG. 2). In addition, in this embodiment, the time slot designation unit 9
It is used as a re-designating unit that re-designates the time slot to be used based on the detection result of the detection unit 6.

Next, in the system as shown in FIG. 9, the case where the mobile station (a) 45 in the A zone and the mobile station (b) 46 in the B zone first talk will be described.

Here, both slave stations 45 and 46 perform call connection control in the main device 41 via the base stations 42 and 43. Therefore, the usage state of the time slot for transmission is as shown in FIG. 10, and a certain frequency is transmitted in time division.

It should be noted that FIG. 10 shows the relationship between the time slot in transmission and the frequency with time. The frequency of F1 is then used for control. Also,
The frequency bands of F2, F3 and F4 are used for transferring audio signals such as data and voice.

Here, one cycle is composed of 8 time slots with a period of 5 ms. Therefore, transfer of approximately 32 kbps is possible in one time slot.

For example, it is assumed that the slave station (b) 46 and the slave station (a) 45 use the frequency F2 shown in FIG.
FIG. 5 shows this one-cycle time slot.

It is also assumed that the time slots # 2 and # 6 shown in FIG. 5 are used for transmission and reception at the time of call setup. In this state, it is assumed that the slave station (c) 47 in the same B zone is talking to another telephone at the same frequency using slots # 3 and # 7.

However, after a certain time has passed, the slave station (c) 4
7 released the call and ended the call. Therefore, the slave station (b)
At 46, the detection unit 6 detects that an empty time slot is secured. After this, under the control of the control unit 5, the request unit 12 monitors the silent state, and starts timekeeping for a predetermined time period.

After that, by detecting the silence for the predetermined time, a call using a plurality of time slots is made again, so that the slave station (b) 46 in the B zone uses the control bit in the same time slot. , A zone slave station (a) 45
Inquiry is made to the base station 42 and the slave station (a) 45 as to whether a plurality of time slots can be secured. Here, when the information indicating that the reservation is possible is returned, the control for the reservation of a plurality of time slots is started between both slave stations and the base station.

At this time, the slave stations 45 and 46 are connected to the base station 42,
The detection unit 6 inside the telephone detects the empty state of the time slot via 43. Then, as shown in FIG. 6, when the time slots can be continuously secured in both the A zone and the B zone, the selection unit 7 selects the output signal 32.

Further, since the slave station (b) 46 can perform transmission / reception using the time slots # 2, # 3, # 6 and # 7, the slave stations (a) and (b) are In both cases, the time slot is designated by the time slot designation section 9 inside the telephone.

Therefore, the selection unit 7 is used to select the codec of 64 kbps and 7 kHz, and it becomes possible to transmit a high quality audio signal for voice transmission.

FIG. 11 is a block diagram showing the structure of a slave station used in the fourth embodiment of the present invention.

The slave station of the fourth embodiment has a structure in which the request unit 12 is omitted from the structure shown in FIG. 8 of the third embodiment. Further, the operation unit 8 of this embodiment is provided with a key 60 for requesting high-quality audio transmission.
In the present embodiment as well, the configuration of the speech codec unit 4 is assumed to be the same as that of the first embodiment (FIG. 2).

FIG. 12 is a front view showing the structure of the operation surface of the telephone terminal of the slave station (b). As shown, a speaker 61 and a microphone 62 are provided on this operation surface.
, 0-9, # and * keys 71, power ON / OF
An F key 72, a call key 73, and an HQ key 74 for requesting high-quality voice transfer are provided. This HQ key 74
Corresponds to the key 60 described above.

Next, similarly to the third embodiment, in the system as shown in FIG. 9, first, the mobile station (a) 45 in the A zone and the mobile station (b) 46 in the B zone call. A case will be described.

Here, both the slave stations 45 and 46 perform call connection control in the main device 41 via the base stations 42 and 43. Therefore, the usage state of the time slot for transmission is as shown in FIG. 10, and a certain frequency is transmitted in time division.

It is also assumed that at the time of call setting, transmission and reception are performed using the time slots # 2 and # 6 shown in FIG. In this state, it is assumed that the slave station (c) 47 in the same B zone is talking to another telephone at the same frequency using slots # 3 and # 7.

Now, in this state, it is assumed that the operator of the slave station (b) 46 presses the above-mentioned HQ key 74. By this operation, the control unit 5 instructs the empty slot detection means of the detection unit 6 to monitor for securing empty slots.

Then, after a certain time has passed, the slave station (c) 4
7 releases the call and terminates, the slave station (b) 46
The detection unit 6 reports the detection signal to the control unit 5.

Therefore, the slave station (b) 46 in the B zone is
Using the control bit in the same time slot, the slave station (a) in the A zone is inquired as to whether a plurality of time slots can be confirmed between the base station 42 and the slave station (a). When the information indicating that reservation is possible is sent back, control for ensuring a plurality of time slots is started between both slave stations and the base station.

At this time, the slave stations 45 and 46 are connected to the base station 42,
The detection unit 6 inside the telephone detects the empty state of the time slot via 43. Then, as shown in FIG. 6, when the time slots can be continuously secured in both the A zone and the B zone, the selection unit 7 selects the output signal 32 of FIG.

In the slave station (b), time slot #
Since it becomes possible to perform transmission / reception using 2, # 3, # 6, and # 7, the slave stations (a) and (b) both specify the time slot in the time slot specifying section 9 inside the telephone. To do.

Therefore, the selecting section 7 is used to select 64 kbps and 7 kHz for the codec circuit, and it becomes possible to transmit a high quality audio signal.

[0056]

As described above, according to the first aspect of the present invention, in the digital cordless telephone system, a plurality of voice signal encoding / decoding means are provided inside the telephone of the slave station and the TDMA / TDD time is set. If continuous time slots can be secured by providing a means for detecting the empty state of slots, by selecting high-quality encoding / decoding means and designating time slots,
This has the effect of enabling high-quality audio signal transmission.

According to the second aspect of the present invention, by providing means for requesting the use of a plurality of time slots during call connection and means for resetting the time slots in response to this request, a call is made once. After setting (establishing), it becomes possible to request high-quality voice transfer even during a call, and if a time slot that enables high-quality transfer can be secured, select a high-quality encoding / decoding means. Re-designating the time slot has the effect of enabling high-quality audio signal transmission.

[Brief description of drawings]

FIG. 1 is a block diagram showing a slave station according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a speech codec section in the first embodiment.

FIG. 3 is an explanatory diagram for explaining a specific operation example in the first embodiment.

FIG. 4 is an explanatory diagram showing a configuration of a time slot in PHP transmission used in the first embodiment.

FIG. 5 is an explanatory diagram showing a usage example of a time slot in the first embodiment.

FIG. 6 is an explanatory diagram showing another usage example of the time slot in the first embodiment.

FIG. 7 is a block diagram showing a slave station according to a second embodiment of the present invention.

FIG. 8 is a block diagram showing a slave station according to a third embodiment of the present invention.

FIG. 9 is an explanatory diagram for explaining a specific operation example in the third embodiment.

FIG. 10 is an explanatory diagram showing a configuration of time slots in PHP transmission used in the third embodiment.

FIG. 11 is a block diagram showing a slave station according to a fourth embodiment of the present invention.

FIG. 12 is a front view showing a configuration of an operation surface of a telephone terminal according to the fourth embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Antenna, 2 ... Wireless circuit part, 3 ... Signal processing part, 4 ... Speech codec part, 5 ... Control part, 6 ... Detection part, 7 ... Selection part, 8 ... Operation part, 9 ... Time slot designation part, 10 ... speaker, 11 ... microphone, 12 ... request part.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication H04M 1/00 P

Claims (2)

[Claims] 1. A digital cordless telephone terminal using a time-division duplex / time-division channel allocation method, and a plurality of encoding / decoding processing means for encoding / decoding voice and an empty slot at the time of call setting. Detecting means for detecting whether or not a plurality of time slots can be used in the usage status of
Selecting means for selecting one of the plurality of encoding / decoding processing means based on a detection signal by the detecting means;
A digital cordless telephone terminal, comprising: a specifying unit for specifying a time slot. 2. In a digital cordless telephone terminal using a time division duplex / time division channel allocation system, a plurality of encoding / decoding processing means for encoding / decoding voice and an empty slot at the time of call setting. Detecting means for detecting whether or not a plurality of time slots can be used in the usage status of
Selecting means for selecting one of the plurality of encoding / decoding processing means based on a detection signal by the detecting means;
Requesting means for requesting the use of a plurality of time slots during call connection, resetting means for resetting the time slots to be used again by the requesting means, and at the time of this resetting, the plurality of encoding / coding A digital cordless telephone terminal, comprising means for switching selection of decoding processing means.