Method for designing channel state information reference signal (CSI-RS) in LTE-A (Long Term Evolution-Advanced) system

Abstract

The invention discloses a method for designing a channel state information reference signal (CSI-RS) in an LTE-A (Long Term Evolution-Advanced) system, belonging to the communication field and being used for measuring the CSI. The method comprises the following steps of: 1, RE capable of being used by the CSI-RS in a PRB; 2, multiplexing mode of the CSI-RS among ports of a cell; 3, CSI-RS mode when the port 5 is not used; 4, CSI-RS mode when the port 5 is used; and 5, allocation of the CSI-RS in a homogeneous network and a heterogeneous network. The method for designing the CSI-RS can not only ensure that a user of an LTE works well in an LTE-A network, reduce the influences on the user of the LTE because of adding the CSI-RS, but also ensures that the CSI-RS in the LTE-A system obtains abigger multiplexing factor, reduces the interference among the CSI-RSs, provides an orthorhombic CSI-RS for a CoMP measuring set, improves the accuracy of channel estimation and enhances the propertyof the system.

Description

technical field [0001] The invention belongs to the technical field of communication, and relates to a design of a channel state information reference signal (CSI-RS) for measuring channel state information (Channel State Information, CSI) in a Long Term Evolution-Advanced (LTE-A for short) system. Background technique [0002] In the LTE system, there are many types of downlink reference signals, each with different functions, such as the Sounding Reference Signal (SRS) used for downlink channel quality measurement, used for downlink channel estimation and user equipment (User Equipment for short) UE) coherently demodulated cell-specific reference signal CRS (Cell-specific Reference Signal), dedicated reference signal DRS (Dedicated Reference Signal) for beamforming, etc. [0003] Advanced LTE (Long Term Evolution-Advanced) is an evolved version of LTE Release-8. In addition to meeting or exceeding all relevant requirements of 3GPP TR 25.913, it must also meet or exceed the...

AI Technical Summary

Problems solved by technology

However, in LTE-A, the system will support antenna configurations up to 8x8. If only CRS multiplexing between antennas is carried out according to the original method, the occupied resource elements (Resource Elements, referred to as REs) will be doubled, greatly increasing System overhead, so 3GPP proposed to divide the newly added CRS into two categories, one is demodulation reference signal (DM-RS) for demodulation, and the other is channel state information for downlink channel estimation Reference signal (CSI-RS), the specific design method of CSI-RS in the world is still under discussion, although some consensus has been achieved, but there are still large differences

In terms of antenna port multiplexing, most domestic companies, such as Huawei, China Mobile, and Datang Telecom, support CDM-F multiplexing. For example, Huawei’s proposal R1-103445 submitted to 3GPP suggests using The multiplexing method of F, which is easy to avoid the consideration of port 5 (AP5), simplifies the design, but this multiplexing method first has defects in backward compatibility, and secondly, in a physical resource block (PRB) The multiplexing factor is also limited and cannot provide a large number of orthogonal reference signals

ZTE's proposal proposes to use CDM-T or a mixed CDM-T and CDM-F multiplexing method, and use a multiplexing factor of 9 in the homogeneous network and a multiplexing factor of 16 in the heterogeneous network, but does not give specific It is the implementation method, and the large multiplexing factor increases the system overhead, and the mixed use of CDM-T and CDM-F increases the difficulty of UE channel estimation

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