SIR Estimation in Wireless Receivers Using Combined Channel Estimates
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for estimating signal to interference ratio (SIR) in wireless communications receivers with multiple transmit antennas are inefficient, particularly due to errors caused by orthogonal DPCH pilot structures, leading to performance degradation under low SIR conditions.
Innovation Solution
A method that calculates first and second variables from received signal samples and pilot symbols for each wireless channel, generates channel estimates, and combines them to estimate signal power, noise power, and SIR, exploiting the structure of dedicated downlink DPCH pilot symbols to efficiently compute these values.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If existing methods are used to estimate SIR in wireless communications receivers with multiple transmit antennas, then the estimation process is simple, but errors are caused by orthogonal DPCH pilot structures leading to performance degradation under low SIR conditions
Solution Approach 1:
The patent segments the channel estimation process into separate first and second channel estimates derived from different orthogonal DPCH pilot structures. By calculating first and second variables from received signal samples and pilot symbols for each channel separately, then combining these estimates, the method reduces errors caused by orthogonal pilot structures while maintaining manageable computational complexity through structured segmentation of the estimation process.
2Productivity
If orthogonal DPCH pilot structures are used in multiple transmit antenna systems, then the pilot and data symbols can be transmitted simultaneously, but errors are introduced in SIR estimation particularly under low SIR conditions
Solution Approach 1:
The patent introduces an intermediary combining step where first and second channel estimates are combined to generate a final SIR estimate. This intermediary process allows the system to benefit from simultaneous pilot and data transmission through orthogonal structures while correcting for the errors they introduce. The combination of separate channel estimates acts as a mediator that reconciles the conflicting requirements of transmission efficiency and measurement precision.
3Measurement precision
If separate channel estimates are generated for each wireless channel, then errors from orthogonal pilot structures are reduced, but the numerical complexity of the estimation process increases
Solution Approach 1:
The patent merges the separate first and second channel estimates into a combined SIR estimate through a structured combining process. By calculating variables from received signal samples and pilot symbols for each channel separately to improve accuracy, then combining these estimates in a unified framework, the method achieves reduced errors from orthogonal pilot structures while controlling overall computational complexity through efficient merging of the separate estimation results.
Data Source
AI summary
A method and corresponding system for generating an estimate of at least one of a signal power, a noise power and a signal to interference ratio for signal samples received via first and second wireless channels, the signal samples corresponding to pilot symbols transmitted in respective different structures via the first and second wireless channels. The method comprises: calculating first and second variables, each variable being a sequence of values computed from the received signal samples and the pilot symbols for each respective first and second wireless channel; generating first and second channel estimates from the first and second variables; combining the first and second channel estimates to generate a combined channel estimate; and generating at least one of the signal power, noise power and SIR using the combined channel estimate.