JP2001510972A - Wireless transmission method and wireless telephone to DECT standard - Google Patents

Abstract

(57) [Summary] According to the present invention, a wireless transmission method between a transmitting device and a receiving device is proposed. Here, an effective channel (B field) is provided for transmitting a voice signal and / or a data signal, and a signaling channel (A field) provided with an error correction code is provided for transmitting signaling data. Upon detecting a signal pause, a signal pause identification signal is transmitted from the transmitting device to the receiving device via the signaling channel, and based on the signal pause signal, the signal received by the valid channel (B field) during the reception of the signal pause identification signal. Is not used. The error correction is applied to the signaling channel, so that the receiving device does not reliably output a signal during a signal pause, and to avoid a transmission error that may occur in an effective channel during a signal pause or when transmitting a mute pattern. Can be.

Description

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a method for wireless transmission between a transmitting device, a receiving device and a wireless telephone, and to a wireless telephone according to the DECT standard.

[0002] Digital wireless telephones according to the DECT (Digital Enhanced Cordless Telephon) standard are increasingly being loved. The technical specifications are, for example, David, Benter "Digitale M
obilfunksystem ", Stuttgart, 1996, Kapital 8.1. The radio interface defined by DECT is a frequency division multiple
Access) and TDMA (Time Division Multiple Access). The used frequency spectrum from 1880 MHz to 1900 MHz is divided into ten carriers each having a channel width of 1728 kHz. Each carrier is divided into 24 time slots as shown in FIG. 1, and these time slots form a frame having a total length of 10 ms. The first twelve time slots are for the uplink from the mobile to the fixed station, and the following twelve time slots are reserved for the downlink from the fixed station to the mobile. A duplex connection is a pair of time slots, eg, time slot 1
1 and a time slot 23. Up and down connection paths are 5
They are separated from each other by a duplex interval of ms.

FIG. 2 is a publication, Components 31 (1993), Heft 6,215-218pp .; S. Althammer, D. Br.
uckmann: From "Hochoptimierte IC's future DECT-Schnurlostelefone", the basic circuit configuration of the base station BS and the mobile unit MT of the wireless telephone facility is shown. According to this, base station B
S and the mobile unit MT have a radio unit FKT with an antenna ANT assigned to transmit and receive radio signals, a signal processing device SVE, and a central control unit ZST, which are interconnected as shown. Have been. The radio unit FKT has a substantially known device,
For example, it includes a transmitter SE, a receiver EM and a synthesizer SYN. The signal processing device SVE includes, for example, an encoding / decoding device CODEC. The central control unit ZST provides an OSI / ISO hierarchical model (Research Report-Deutsche Telekom, Jg. 48, 2/1995, 102-111pp .; (2)) for both the base station BS and the mobile unit MT.
: ETSI-Publikation ETS 300175-1 ... 9, see Oktober 1992) having a microprocessor μP with a program module, a signal control unit SST, and a digital signal processor DSP, So that they are interconnected. Among the layers defined in the hierarchical model, the base station BS and the mobile station MT
The first four layers that are directly relevant to are illustrated. The signal control unit SST is configured as a time switch controller TSC in the base station BS, and as a burst mode controller BMC in the mobile unit MT. These two signal control units T
An important difference between SC and BMC is that the base station-specific signal control unit TSC additionally performs a switching function with respect to the mobile station-specific signal control unit BMC.

The basic functions of the circuit unit configured as described above are described in, for example, the publication “Components”.
31 (1993), Heft 6,215-218pp.

[0005] Considering that 10 carrier frequencies are used as already mentioned, the total capacity is 120 full-duplex channels. The DECT radio system automatically selects the channel with the best connection quality.

FIG. 1 shows at the bottom the structure of an individual time slot having a duration of 416.6 μs, corresponding to 480 bits. First, there is a guard band having 60 bits. This is to enable reliable separation from adjacent time slots. Of the remaining 420 bits, 32 bits are used for synchronization (S field),
Bits are used for parity check (X field). Sixty-four bits are used for the signaling channel (A field), of which sixteen bits are error codes, for example, a cyclic redundancy check (CRC). The remaining 48 bits are used for signaling, for example, for information on connection establishment, exchange of identifiers, transfer to another netcell (handover). The signal speed of the full-duplex channel is, for example, 64 bits / 10 ms = 6.4 kbit / s. Data transmitted on the signaling channel is protected from transmission errors by error correction bits. In contrast, the 320 bits of the effective channel (B field) are not specially protected against transmission errors. The transmission speed of the effective channel is 32 kbit / s.

[0007] From DE 195 15 546 A1, a method and a device are known for transmitting a voice signal and a data signal between a transmitting device and a receiving device over the same wireless channel. At the transmitting device, the data signal is transmitted to the receiving device via the same wireless channel as the voice signal, together with at least one control signal for indicating the voice pause, and the data signal is separated from the control signal at the receiving device, and during the voice pause, Is output to Thus, when a voice pause occurs and no voice signal is transmitted, the data signal is transmitted and received over the same wireless channel. As a result, the load on the wireless transmission path is reduced in terms of information transmission in both transmission directions.

[0008] From DE 42 36 008 A1, a method is known for reducing the disturbing effect of voice transmission quality, which has deteriorated during a telephone connection with a wireless telephone device. In this method, the A field of the DECT burst governs the information associated with the connection, and when a telephone connection is made between the base station part and the mobile part of the radiotelephone device according to the DECT standard, the audio ADPC is performed.
Click noise and interference noise caused by a bit error during M transmission are prevented by silent switching (muting of a voice signal) performed in each part of the wireless telephone device.

If a signal pause in the DECT radiotelephone mobile occurs, for example, due to a radiotelephone user's voice pause, ambient noise is transmitted to the fixed station and then to the other party on the B channel, or the terminal terminates the signal pause. Silence signal (large mute signal) when detected
May be transmitted to the other party. In the former case, the ambient noise feels rather disturbing, especially if the sensitivity of the microphone is adapted to the detected signal level. In the latter case, when a silent signal is transmitted on an effective channel (B field), it is decoded as normal acoustic data on the receiving side, and if received without error, a "quiet" is formed in the receiving speaker. However, if a transmission error occurs in this mute signal, severe interference noise may instead occur.

An object of the present invention is to provide a wireless transmission method between a transmitting device and a receiving device and a wireless telephone so as to improve transmission quality. In particular, the occurrence of a disturbance signal or disturbance noise is prevented even in the event of a signal pause.

The present invention proposes the following wireless transmission method between a transmitting device and a receiving device.
That is, in this method, when a signal pause is detected, a signal pause identification signal is transmitted from the transmitting device to the receiving device via the signaling channel (A field). It does not use the signal received on the active channel and advantageously does not perform any decoding and / or amplification. This is because the signaling pause identification signal is a signaling channel (
This is because the transmission is performed in the (A field), so that the occurrence of transmission errors at the time of signal suspension can be significantly reduced.

The method according to the invention can be applied, inter alia, to digital radio telephones according to the DECT standard.

The present invention also proposes a radiotelephone having a device for detecting a signal pause and a device for transmitting a signal pause identification signal when a signal pause is detected.

The working principle of the method according to the invention will be described below with reference to the drawings based on embodiments.

FIG. 1 shows an example of a time frame structure used in the method of the present invention.

FIG. 2 shows a block circuit diagram of a known radio telephone device according to the DECT standard.

Wireless telephones are typically used in combination with a base station and one or more mobile stations. A signal is transmitted from the mobile station to the base station via radio. The base station is further connected to a telephone network and signals are transmitted to the other party. The call partner can use a fixed network telephone, a wireless telephone, a mobile telephone, or the like. Time slots 1 to 11 are reserved for transmitting signals from the base station to the mobile unit, and time slots 12 to 23 are reserved for transmitting signals from the mobile device to the base station (uplink connection). The base station and the mobile unit can be configured as shown in FIG. However, the central control unit ZST of the mobile unit MT has an additional device, which identifies a signal pause, ie a voice pause of the subscriber in the mobile unit or the like, with an input level below a set value. When a signal pause or signal interruption is identified, a signal pause identification signal P
Is transmitted in the A field, that is, on the signaling channel of the time slot. The fixed station identifies the signal pause identification signal P in the A field and interrupts decoding, amplification and / or conduction of the signal received in the B field. Since the signaling data in the A field is protected from transmission errors by error correction coding (CRC), the signal pause identification signal can be transmitted reliably. Transmission impairments that may be included in the received data of the B field that are not error correction coded are not further transmitted from the fixed station and are therefore not heard by the receiving device. Therefore, the transmission quality of the DECT-free advertising system of the present invention is improved.

[Brief description of the drawings]

FIG. 1 shows an example of a time frame structure used in the method of the present invention.

FIG. 2 shows a block circuit diagram of a known radio telephone device according to the DECT standard.

[Procedural Amendment] Submission of translation of Article 34 Amendment of the Patent Cooperation Treaty

[Submission date] January 18, 2000 (2000.1.18)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Name of invention

[Correction method] Change

[Correction contents]

Title: Wireless transmission method and telephone system to DECT standard

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0001

[Correction method] Change

[Correction contents]

The present invention relates to a method for wireless transmission between a transmitting device, a receiving device and a wireless telephone, and a telephone system according to the DECT standard.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction contents]

[0007] From DE 195 15 546 A1, a method and a device are known for transmitting a voice signal and a data signal between a transmitting device and a receiving device over the same wireless channel. At the transmitting device, the data signal is transmitted to the receiving device via the same wireless channel as the voice signal, together with at least one control signal for indicating the voice pause, and the data signal is separated from the control signal at the receiving device, and during the voice pause, Is output to Thus, when a voice pause occurs and no voice signal is transmitted, the data signal is transmitted and received over the same wireless channel. As a result, the load on the wireless transmission path is reduced in terms of information transmission in both transmission directions. In order to prevent the occurrence of disturbing signals and disturbing noises during the transmission of the voice pause, the receiver amplifier of the receiving device during the voice pause is replaced by a noise signal which is formed by the receiving device and which has no transmission error. Supplied. Therefore, the signal received on the effective channel is not further processed in the receiving device.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction contents]

An object of the present invention is to provide a wireless transmission method between a transmitting device and a receiving device, and a telephone system for wirelessly transmitting between a transmitting device and a receiving device, in which a transmission error occurs during transmission of a signal pause. Is remarkably reduced. This object is achieved, according to the invention, by starting from the method defined in the preamble of claim 1. This object is further achieved by a configuration according to the characterizing part of claim 4, starting from a telephone system as defined in the preamble of claim 4.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction contents]

The present invention proposes a method and a telephone system for wireless transmission between a transmitting device and a receiving device as described below. That is, in the method and the system, when the signal pause is detected, the signal pause identification signal is transmitted from the transmitting device to the receiving device via the signaling channel (A field), and the receiver receives the transmission pause identification signal based on the signal pause identification signal. It does not use the signal received on the active channel, and advantageously does not perform any decoding and / or amplification. This is because the signal pause identification signal is transmitted on the signaling channel (A field) protected against transmission errors, so that the occurrence of transmission errors during signal pauses can be significantly reduced.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0012

[Correction method] Change

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[0012] Further refinements of the invention are described in the dependent claims.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0013

[Correction method] Deleted

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0014

[Correction method] Change

[Correction contents]

The principle of the method of the present invention or the functional principle of the telephone system of the present invention will be described below based on embodiments with reference to the drawings.

[Procedural Amendment] Submission of translation of Article 34 Amendment of the Patent Cooperation Treaty

[Submission date] January 18, 2000 (2000.1.18)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

Claims (5)

[Claims] 1. A method for wireless transmission between a transmitting device (BS, MT) and a receiving device (MT, BS), comprising: an effective channel (B field) for transmitting a voice signal and / or a data signal. In a method in which a signaling channel (A field) with an error correction code is provided for transmitting signaling data, when a signal pause is detected from a transmitting device (BS, MT) via a signaling channel The signal pause identification signal (P) is transmitted to the receiving device (MT, BS), and based on this, the receiving device (MT, BS) receives the signal received on the effective channel while receiving the signal pause identification signal (P). Transmission method, wherein the transmission method is not further processed. 2. The method according to claim 1, wherein the receiving device (MT, BS) does not decode and / or amplify the signal received on the active channel during reception of the signal pause identification signal. 3. The transmitting device (BS, MT) and the receiving device (MT, BS)
The method according to claim 1 or 2, wherein the method is a wireless telephone according to the DECT standard. 4. A radiotelephone for use in a telephone system, wherein an effective channel (B field) for transmitting voice and / or data signals is provided with an error correction code for transmitting signaling data. In a radio telephone provided with a signaling channel (A field), a radio telephone (BS, MT) includes a device for identifying a signal pause and a signal for transmitting a signal pause identification signal when a signal pause is identified. Equipment (ZST, SVE, FKT
, ANT). 5. The radio telephone according to claim 4, wherein the radio telephone (BS, MT) is a digital radio telephone according to the DECT standard.