Multi-Antenna Interference Cancellation via Dirty Paper Coding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Multi-antenna systems in wireless communication face challenges in achieving maximum channel capacity and ensuring Quality of Service (QoS) per user due to interference, with linear schemes degrading performance and nonlinear schemes failing to guarantee constant transmission rates and QoS.
Innovation Solution
The system employs a method for generating a precode that maximizes diversity gain using channel information from receive antennas, updates transmit powers to account for power loss and shaping loss, and performs dirty paper coding on precoded signals to transmit effectively, ensuring QoS and reducing error propagation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If linear interference cancellation schemes (ZF or MMSE) are used, then implementation complexity is reduced and error rate remains acceptable, but maximum channel capacity cannot be achieved
Solution Approach 1:
The patent segments the interference cancellation process into two distinct stages: first applying linear precoding (ZF or MMSE) to obtain an initial estimate, then applying nonlinear processing (DPC/THP) to refine the cancellation. This segmentation allows the system to benefit from both the simplicity of linear methods and the capacity advantages of nonlinear methods, resolving the contradiction between implementation complexity and channel capacity.
2Productivity
If nonlinear precoding schemes (DPC, THP, or VP) are used, then maximum channel capacity is achieved, but constant transmission rate per user and QoS cannot be guaranteed
Solution Approach 1:
The patent introduces feedback mechanisms where the receiver sends channel state information and quality metrics back to the transmitter. This feedback enables the transmitter to adjust precoding matrices and power allocation dynamically, ensuring that QoS requirements are met while maintaining high channel capacity through nonlinear precoding.
3Ease of manufacture
If linear schemes are used, then implementation is easier, but transmit power is wasted and performance degrades unless channels are orthogonal
Solution Approach 1:
The patent applies preliminary nonlinear precoding processing at the transmitter before signal transmission. By pre-subtracting interference components using DPC/THP algorithms, the system eliminates the need for orthogonal channels and reduces transmit power waste, while maintaining implementation feasibility through structured preprocessing steps.
Data Source
AI summary
An apparatus and a method for interference cancellation in a transmitting end of a multi-antenna system are provided. A precode is generated which maximizes a diversity gain of one or more receive antennas using channel information of the receive antennas to be serviced. Transmit powers of the receive antennas are updated by taking into account a power loss and a shaping loss according to a dirty paper coding. Transmit signals are precoded by updating the precode according to the updated transmit powers. The dirty paper coding is performed on the precoded transmit signals to be transmitted to the receive antennas.