A synchronization method and device for non-IP data transmission

Abstract

The application discloses a synchronization method for Non-IP data transmission, comprising: the receiving party receives stream information and time information of the voice stream in the real-time transport protocol RTP packet from the sending party; the receiving party saves the received information and records the current time System frame number SFNi of the system frame number SFNi, obtain the mapping relationship between the time information and the system frame number SFNi; when the receiver receives the voice packet that adopts Non-IP mode transmission from the sender, obtain the system frame number SFNj of the current moment, Calculate the relative time difference between SFNi and SFNj, calculate the relative time stamp of the voice packet according to the time information, and recover the corresponding RTP time stamp. The present application also provides a corresponding device. Applying the technical solution disclosed in this application can enable the receiver to restore the absolute time and relative time of the voice packet in the multi-stream concurrent scenario, realize multi-stream synchronization, and thus restore the synchronous playback of video and audio.

Description

technical field [0001] The present application relates to the field of communication technologies, and in particular to a method and device for synchronizing Non-IP data transmission. Background technique [0002] With the continuous development of wireless communication technology, wireless technology has developed from 2G to 4G, and some technologies of 4.5G and 5G are gradually introduced. The data transmission of the wireless mobile Internet is also mainly based on IP. However, when transmitting services with a small amount of data, such as voice services or small data packets of the Internet of Things, if the data is transmitted in the IP packet format, the data transmission efficiency is too low. [0003] For example: the voice packet format of AMR commonly used in wireless communication is as follows figure 1 shown. according to figure 1 : Class A, Class B and Class C of the AMR speech frame are 244bit, and the total speech frame plus supplementary bits is a maxim...

AI Technical Summary

Problems solved by technology

[0008] In multimedia services, due to the small length of the voice packet, when the above-mentioned AMR Over PDCP method is used for transmission, the sender will take out the voice payload (Payload) and transmit it using the AMR Over PDCP method. Contains a timestamp, so that the receiver will not be able to obtain the timestamp and can only play it in the order it was received

If it is a video and audio dual-stream scenario, the receiver cannot synchronize audio and video playback; in other scenarios, similar problems exist in scenarios such as multi-stream voice mixing using the AMR Over PDCP transmission method

[0009] It can be seen that when the prior art adopts non-IP (Non-IP) mode, such as the AMR Over PDCP mode to transmit the business of small-length data packets such as multimedia voice, since the RTP header is not transmitted, the time-related information in the RTP and RTCP headers (Information such as time stamp) will be lost, resulting in the inability of the receiver to recover the time information, and in multi-stream or dual-stream transmission scenarios such as audio and video, the receiver cannot synchronize audio and video playback

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