JPH08317023A - Digital mobile phone - Google Patents

Abstract

(57) [Summary] [Structure] Microphone 1, A / D converter 2, speech coder / decoder selector 3, 4, 5, 6, full rate speech coder 7, half rate speech coder Device 8, full-rate speech decoder 9, half-rate speech decoder 10, switching devices 11, 12, 13, 14, 18, 19, 20, 21,
A digital mobile phone including a storage device 15, a transceiver 16, an antenna 17, a D / A converter 22, and a speaker 23. [Effect] The efficiency of the storage unit is improved, the storage capacity consumed per hour becomes constant, and the recording time becomes the longest.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital mobile phone having at least a voice coding unit, a voice decoding unit and a storage unit.

[0002]

2. Description of the Related Art Conventional mobile telephones are often used while moving outdoors and have the disadvantage that a memo sheet must be filled in when recording a conversation during a call.

In response to such inconvenience, a method of connecting a voice input / output terminal to a portable telephone and connecting a voice storage device such as a tape recorder to the outside, or a voice encoder and a digital memory to set the contents of a call to a digital memory The method of storing is implemented.

The latter method can also be applied to a digital mobile phone (see Japanese Patent Laid-Open No. 4-29447).

[0005]

The digital mobile phone can be provided with a plurality of voice encoders having different encoding speeds according to the Japanese standard. Specifically, a full-rate speech encoder that encodes speech at an encoding rate of 11.2 kilobits per second and a half-rate speech encoder that encodes speech at an encoding rate of 5.6 kilobits per second are provided. be able to. However, the encoded data by the full-rate speech encoder and the half-rate speech encoder are encoding methods that do not have connectivity with each other, and in conventional digital mobile phones, this different encoded data must be mixed. Since it is stored in the digital memory, the efficiency is very poor and there is a problem that it cannot be used.

Further, since the encoded data by the full-rate speech encoder and the half-rate speech encoder have different storage capacities per time, depending on the degree of use of the full-rate speech encoder and the half-rate speech encoder. However, there is a problem that the maximum storage time differs greatly because the capacity that can be stored in the digital memory is different.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and includes a voice encoder for encoding voice, a voice decoder for decoding encoded voice,
In a digital mobile phone having a storage unit for storing encoded voice, a plurality of voice encoding units having different encoding speeds are provided, and the storage unit is the lowest in the plurality of voice encoding units. This is a digital mobile phone that stores only data encoded at the encoding speed.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, a digital mobile phone of the present invention is provided with a voice coder / voice decoder having two different coding speeds, and includes a microphone 1, an A / D. Converter 2, speech coder / decoder selector 3, 4, 5, 6, full-rate speech coder 7, half-rate speech coder 8, full-rate speech decoder 9, half-rate speech decoding Device 10, switching device 11, 12, 1
3, 14, 18, 19, 20, 21, a storage device 15, a transceiver 16, an antenna 17, a D / A converter 22, and a speaker 23.

In a normal call state, the combination of one of the full-rate speech encoder 7 and the full-rate speech decoder 9 or the combination of the half-rate speech encoder 8 and the half-rate speech decoder 10 is used for speech coding. It is selected by the switching units 3, 4, 5, 6 of the decoder / decoder.

When the full rate speech encoder 7 and the full rate speech decoder 9 are selected, the speech input from the microphone 1 is converted into digital speech data by the A / D converter 2, and the full rate speech encoder is selected. The encoded voice data is encoded by 7 at the encoding rate of 11.2 kilobits per second and transmitted to the base station by the transceiver 16 and the antenna 17. Further, the encoded voice data coming from the base station is received by the antenna 17 and the transceiver 16, decoded by the full rate decoder 9 into digital voice data, converted into an analog signal by the D / A converter 22, and the speaker 23. Output by.

According to the present invention, when the full-rate speech encoder 7 and the full-rate speech decoder 9 are selected when recording the conversation content during a call, the storage device 15 is used after converting to the half-rate encoding rate. It is characterized by storing in.

The operation for conversion will be described below. When recording the conversation of the user during a call, the voice data encoded by the full-rate voice encoder 7 is transmitted / received by the transmitting / receiving device 16,
While being sent to the antenna 17, it is input to the storage device 15 by the switch 12 and temporarily stored.

To record the conversation of the other party during a call, the encoded voice data received from the antenna 17 and the transmitter / receiver 16 is sent to the full rate decoder 9, while the switch 19 is used.
Is input to the storage device 15 and is temporarily stored. The encoded voice data that is temporarily stored in the storage device 15 is the voice data that is encoded by the full rate encoder on the other side.

Next, after the call is ended, the voice data encoded at the full-rate encoding rate temporarily stored in the storage device 15 by the switching device 19 is automatically or arbitrarily operated by the operator. read out.

After that, the full-rate decoder 9 decodes it into digital audio data, and the switch 18 and the storage device 15
Is read by the switching unit 13 via the, and encoded by the half-rate speech encoder 8 to a half-rate coding rate (5.6 kilobits per second) and written in the storage unit 15 by the switching unit 14. After conversion into the coding rate of the rate, it is stored in the storage device 15.

The conversion operation of the coding rate may be performed in real time during a call in the case of a mobile phone having a sufficient signal processing device capability.

When the call uses the half-rate speech encoder 8 and the half-rate speech decoder 10, the encoded speech data is transferred from the switch 14 or the switch 21 to the storage device 1.
5 need not be changed and the coding rate need not be changed.

As described above, by storing only the voice data encoded by the voice encoder having the lowest coding rate (specifically, the half-rate voice encoder 8) in the storage device 15, the storage device is obtained. The efficiency of 15 becomes very good, the storage time of the storage device 15 becomes constant, and the storage time becomes maximum.

In the present embodiment, the case of a digital type mobile phone provided with two voice encoders and voice decoders having different encoding speeds has been described, but a plurality of encoding speeds of two or more encoding speeds are described. Even for digital type mobile phones provided with different voice encoders and voice decoders, voice data encoded by the voice encoder with the lowest coding speed is always recorded in the recording device 15. If constituted, the effect of the present invention can be obtained similarly.

[0021]

As described above, according to the digital portable telephone of the present invention, the efficiency of the storage unit is improved by storing only the one encoded at the lowest encoding speed in the storage unit. Thus, it is possible to provide a digital mobile phone in which the storage capacity consumed per hour is constant and the recording time is maximum.

[Brief description of drawings]

FIG. 1 is a block diagram showing a digital mobile phone of the present invention.

[Explanation of symbols]

1: Microphone 2: A / D converter 3, 4, 5, 6: Switch of audio encoder / decoder 7: Full-rate audio encoder 8: Half-rate audio encoder 9: Full-rate audio decoding Device 10: Half rate speech decoder 11, 12, 13, 14, 18, 18, 19, 20, 21: Switching device 15: Storage device 16: Transceiver 17: Antenna 22: D / A converter 23: Speaker 23

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location H04M 11/10 H04B 7/26 Q

Claims (1)

[Claims] 1. A digital mobile phone having a voice encoding unit for encoding voice, a voice decoding unit for decoding encoded voice, and a storage unit for storing the encoded voice, The speech coding unit has a plurality of units having different coding rates, and the storage unit stores only the speech coded at the lowest coding rate of the plurality of speech coding units. Digital mobile phone.