Multi-user detection method for SCMA (Sparse code multiple access) communication system for dynamic message scheduling

Abstract

The invention discloses a multi-user detection method for an SCMA (Sparse code multiple access) communication system for dynamic message scheduling and belongs to the field of single detection of the wireless communication system. The method adopts a dynamic scheduling strategy and utilizes a residual (the difference degree before and after updating of one message) as a measurement criteria. During each of the second to tmaxth iteration processes, the method comprises the following steps of firstly, selecting a user node ujmax and a resource node ckmax which are corresponding to a maximum residual value according to the residual values from all user nodes to resource nodes, which are computed in the last iteration; updating messages from the resource node ckmax to all corresponding user nodes except for the user node ua of the ujmax; and updating messages from the user node ua to all corresponding resource nodes except for the user node cb of the ckmax. According to the method, the dynamic scheduling method updates the non-convergent node messages in the iteration preferentially, so that the iterative decoding convergence rate of the whole codon can be accelerated; the updated node messages are utilized in real time in each iteration, so that the utilization rate of the updated nodes can be effectively improved; and the computational complexity is low and the BER (Bit Error Rate) performance is excellent.

Description

technical field [0001] The invention belongs to the field of signal detection of wireless communication systems, and relates to a multi-user detection method of a sparse code multiple access (SCMA) uplink communication system with fast convergence speed, in particular to a multi-user detection method of dynamic message scheduling, which is used for Solve the multi-user detection problem of the future 5G (fifth generation mobile communication) mobile communication alternative multiple access technology. Background technique [0002] Multiple access is one of the core technologies of the physical layer of wireless communication, which enables the base station to distinguish and serve multiple end users at the same time. In order to meet the requirements of 5G (fifth generation mobile communication) for large capacity, massive connections, and low-latency access, it was proposed in the invention patent "System and Method for Sparse Code Multiple Access" with application number ...

AI Technical Summary

Problems solved by technology

However, in practical engineering applications, as the number of iterations increases, the hardware calculation complexity of the communication system is getting higher and higher, so the hardware requirements are also getting higher and higher; and in this method, all resource nodes to user node messages renew is the message from the user node to the resource node obtained based on the t-1th iteration Update of all user node to resource node messages is updated based on the current iteration Although Make good use of the current iterative update but is generated based on the previous iteration The update message from user nodes to resource nodes in the current iteration is not fully utilized, resulting in a low convergence rate

In summary, although the above parallel MPA detection method can effectively improve the probability of correct decoding, it cannot meet the high-speed and high-efficiency requirements of 5G due to its high computational complexity and low convergence rate.

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