Communication method and device

Abstract

Provided are a communication method and apparatus, which relate to the field of communications, and are particularly suitable for a broadcast system, the method comprising: a terminal device receivesa first downlink channel from an access network device, with the first downlink channel being scrambled by a first identifier and being used for bearing first data; and the terminal device receives asecond downlink channel from the access network equipment, the second downlink channel is scrambled by a second identifier and is used for retransmitting the first data, and the first identifier and the second identifier are identifiers configured by the access network equipment. Through the method, a feedback retransmission mechanism combining broadcast initial transmission and local retransmission can be realized, and thus the spectral efficiency of a communication system is improved.

Description

technical field [0001] The present application relates to the communication field, and in particular to a communication method and device. Background technique [0002] In the prior art, the downlink data transmission services provided by the wireless communication system for terminal devices can generally be classified into two types: unicast services and broadcast-multicast services. [0003] Unicast is a point-to-point communication, that is, a single-point communication between a network device and a terminal device. The network device can send data for each terminal device to achieve personalized services, but when the number of terminal devices is large and the access traffic of the terminal device When the network is large, all unicast data transmission methods will overwhelm the network equipment. Broadcast and multicast can support point-to-multipoint communication, that is, network devices transmit the same data to multiple terminal devices, such as mobile TV serv...

AI Technical Summary

Problems solved by technology

In the broadcast data transmission method, all terminal devices located in the local area network will receive the data transmission, broadcast does not need to do path selection, so the network cost is low, but it cannot provide personalized services to many terminal devices receiving data

Multicast is to transmit data to a group of terminal devices. Terminal devices that need the same data stream can share a data stream, which can provide richer services than broadcast while reducing the load on network devices. However, compared with unicast, multicast There is no error correction mechanism, and the communication quality will be seriously affected when packet loss occurs, so it is necessary to use a more robust modulation and coding method, resulting in low spectral efficiency

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