DTMF (dual-tone multifrequency) sound transferring method and device

Abstract

The invention relates to a DTMF (dual-tone multifrequency) sound transferring method, which comprises the following steps: confirming a forward RTP (real-time protocol) grouping from a media gateway as a DTMF frame through a BSS (base station subsystem) after creating a voice calling, and then processing the DTMF frame so as to obtain a corresponding in-band DTMF signaling frame and send the in-band DTMF signaling frame to an MS (memory system). The invention also provides a DTMF sound transferring device, which comprises a BSS, wherein the BSS comprises a detection unit, a processing unit and a sending unit; the detecting unit is used for detecting the forward RTP grouping from the media gateway as the DTMF frame after creating the voice calling; and the processing unit is used for processing the DTMF frame so as to obtain the corresponding in-band DTMF signaling frame and send the in-band DTMF signaling frame to the MS through the sending unit. Under the transferring mode of IP exchange technique, the BSS digitally processes the DTMF in the forward RTP grouping from the media gateway into the in-band DTMF signaling frame and sends to the MS in the manner of in-band DTMF signaling frame, so as to successfully send the DTMF digital A-D in the forward RTP grouping from the media gateway to the MS, overcome the defects of the prior art that the DTMF digital A-D (analog-digital) can not be sent to the MS, and efficiently realize various services related to DTMF.

Description

technical field [0001] The invention relates to a method and a device for transmitting DTMF tones of a traditional mobile terminal domain (LMSD: Legacy Mobile Station Domain) in a CDMA2000 system. Background technique [0002] The packet-based CDMA2000BSS (Base Station Subsystem) can use IP (Internet Protocol) switching technology to access the CDMA2000 core network based on software switching. Compared with the traditional circuit domain MSS (Mobile Switching Subsystem) system, the biggest change of the CDMA2000 core network based on software switching lies in the separation of call control and bearer, and the replacement of TDM (Time Division Multiplexing) with packet network technology. Using) technology, traditional MSC (Mobile Switching Center) network elements evolve into MSCe (Mobile Switching Center emulation) and MGW (Media GateWay). MSCe provides call control and mobility management functions. The MGW provides media control functions and transmission resources, an...

AI Technical Summary

Problems solved by technology

The second is to use Send Burst DTMF message transmission on the air interface. In this case, when using the original TDM transmission method to realize the transmission of DTMF tones, the CDMA access network needs to reverse the DTMF digits received from the air interface signaling through the voice The coder converts the pulse code modulation (Pulse Coded Modulation: PCM) code stream into the media gateway through the TDM circuit. In the forward direction, the in-band DTMF tone needs to be detected from the PCM code stream transmitted from the TDM circuit through the vocoder, and the BSS sends the The obtained DTMF digits are sent to the terminal through the air interface Send BurstDTMF message; the transmission method of the later IP switching technology is adopted, and the PCM code stream is no longer used between the CDMA access network and the MGW, but the voice frame needs to be directly processed according to the protocol. The RTP (Real-Time Transport Protocol) packet is transmitted through the IP network. At this time, for the DTMF tone, the IP network transmission needs to be encapsulated and decapsulated according to the RFC4733 protocol, and the CDMA access network needs to reverse the signal from the air interface. The received DTMF digits are encapsulated according to the RFC4733 protocol, and transmitted to the media gateway on the IP network. The forward direction needs to decapsulate the RFC4733 protocol frame from the IP network, and transmit the obtained DTMF digits through the air interface Send Burst DTMF message For the terminal, however, there is a problem here. According to the RFC4733 protocol in the RTP packet, a total of 16 DTMF digits 0-9, *, #, A-D are defined, but only 0-9 are defined in the air interface Send Burst DTMF message , *, # There are 12 DTMF digits in total. At this time, if BSC receives the DTMF digits of A-D, it will not be able to transmit them to the terminal

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