A kind of pilot allocation method

Abstract

The invention discloses a method for allocating pilot frequencies. In the method, the service priority of a cell is divided into four priorities: A, B, C, and D. Different service priorities are assigned different pilot sets. The pilot sets allocated by a cell The higher the orthogonality, the lower the probability that users in the cell will reuse pilots with users in other cells. In order to measure the influence of a single user on the system when pilot multiplexing occurs, the pilot pollution intensity is introduced. After the pilot set is allocated, the pilot pollution intensity of users in each cell is calculated again, and the pilots are redistributed for users with higher pilot pollution intensity. The present invention introduces a pilot-based channel estimation technique in the pilot allocation, which can accurately estimate the current channel state, thereby judging whether the cell users are polluted by the pilot. By applying the solution provided by the embodiment of the present invention, the actual demand of each cell can be taken into consideration, the average reachability and rate of users of the Massive MIMO system can be improved, and pilot pollution can be reduced to a large extent.

Description

technical field [0001] The invention relates to wireless communication technology, in particular to a pilot allocation method suitable for Massive MIMO systems. Background technique [0002] As a key technology of 5G, Massive MIMO will play a vital role in the development of 5G. Massive MIMO is also called a large-scale antenna system. The number of base station antennas is as few as dozens, as many as hundreds, or even thousands. Massive MIMO has advantages that traditional MIMO cannot match. However, due to the limitation of pilot resources, there must be pilot multiplexing among users, so that the base station cannot correctly identify the pilots from multiple cells and multiple users, and thus cannot perform accurate channel estimation on the uplink channel, that is, pilot pollution The phenomenon of pilot frequency pollution seriously hinders the normal transmission of user signals. When the number of users increases, the phenomenon of pilot frequency pollution becomes...

AI Technical Summary

Problems solved by technology

[0009] Traditional pilot pollution mitigation algorithms do not take business information into account, but in practice, different businesses have different requirements

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