Sampling Phase Determination Using Shifted Symbol-Period Sampling

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

High sampling rates required in wireless communication devices for bandwidth communication systems lead to increased hardware costs and power consumption, which is undesirable for low-cost, handheld devices.

Innovation Solution

Sampling the received signal at a period of T+m*(T/n) during the sampling phase determination process, where T is the symbol or chip period, n is the number of phases, and m is a fixed non-zero integer, allowing for reduced oversampling and subsequent correlation to identify optimal sampling phases without the need for high oversampling rates.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If high sampling rates are used in bandwidth communication systems, then signal recovery accuracy is improved, but hardware cost and power consumption increase

Engineering Contradiction:
Improvesignal recovery accuracyVSAvoidpower consumption
Core Design Contradiction:
Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent applies partial oversampling by using a sampling rate that is higher than the minimum Nyquist rate (2B) but lower than traditional oversampling rates (4B or 8B). Specifically, it uses a sampling rate of approximately 2.2B to 2.5B, which provides sufficient accuracy for sampling phase determination without the excessive power consumption of higher sampling rates. This partial action principle resolves the contradiction by finding an intermediate sampling rate that achieves adequate signal recovery accuracy while minimizing power consumption.

Inventive Principle:
Principle #16Partial or excessive action

Solution Approach 2:

The patent changes the sampling rate parameter from traditional high values (4B or 8B) to a optimized range (2.2B to 2.5B). This parameter change allows the system to maintain effective signal recovery and sampling phase determination while significantly reducing the power consumption and hardware cost associated with higher sampling rates. The parameter optimization directly addresses the contradiction between accuracy and energy usage.

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If high sampling rates are used in bandwidth communication systems, then signal recovery accuracy is improved, but hardware cost increases

Engineering Contradiction:
Improvesignal recovery accuracyVSAvoidhardware cost
Core Design Contradiction:
Measurement precisionVSEase of manufacture

Solution Approach 1:

The patent applies partial oversampling by using a sampling rate that is higher than the minimum Nyquist rate (2B) but lower than traditional oversampling rates (4B or 8B). Specifically, it uses a sampling rate of approximately 2.2B to 2.5B, which provides sufficient accuracy for sampling phase determination without the excessive hardware cost of higher sampling rates. This partial action principle resolves the contradiction by finding an intermediate sampling rate that achieves adequate signal recovery accuracy while minimizing hardware cost.

Inventive Principle:
Principle #16Partial or excessive action

Solution Approach 2:

The patent changes the sampling rate parameter from traditional high values (4B or 8B) to a optimized range (2.2B to 2.5B). This parameter change allows the system to maintain effective signal recovery and sampling phase determination while significantly reducing the hardware cost associated with higher sampling rates. The parameter optimization directly addresses the contradiction between accuracy and manufacturing cost.

Inventive Principle:
Principle #35Parameter changes

3Measurement precision

If oversampling by n samples per modulation symbol is performed, then sampling phase determination accuracy is improved, but sampling rate and power consumption increase

Engineering Contradiction:
Improvesampling phase determination accuracyVSAvoidpower consumption
Core Design Contradiction:
Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent applies partial oversampling for phase determination by using a sampling rate that provides sufficient phase accuracy without excessive oversampling. Instead of using n=4 or n=8 samples per symbol, the patent uses a sampling rate of approximately 2.2B to 2.5B, which corresponds to partial oversampling (n≈1.1 to 1.25). This resolves the contradiction by achieving adequate phase determination accuracy with minimal power consumption.

Inventive Principle:
Principle #16Partial or excessive action

Solution Approach 2:

The patent changes the oversampling parameter n from traditional values (4 or 8) to a optimized range corresponding to sampling rates of 2.2B to 2.5B (n≈1.1 to 1.25). This parameter change maintains sampling phase determination accuracy while significantly reducing power consumption. The optimized parameter directly addresses the contradiction between phase accuracy and energy usage.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentUS7616707B2Methods and apparatus for reducing a sampling rate during a sampling phase determination process
Publication Date: 2009.11.10 MALIKIE INNOVATIONS LTD
  • US7616707B2 patent drawing
  • US7616707B2 patent drawing
  • US7616707B2 patent drawing

AI summary

A received signal is sampled at a sampling period of T+m*(T/n) during a sampling phase determination process. T is a symbol or chip period of the received signal, n is a number of phases of the sampled signal, T/n is a phase resolution period, and m is a fixed non-zero integer value where −n<m<n (e.g. m=1 or −1). By sampling the received signal at the sampling period of T+m*(T/n), a sample set for each one of n phases of the sampled signal is produced. For each sample set, a correlation process is performed between the sample set and a predetermined correlation signal to produce a correlation result. Once an optimal correlation result is identified from the correlation process, the received signal is sampled at a sampling period of T at a phase associated with the optimal correlation result. Advantageously, oversampling at a sampling rate of n/T is not required during the sampling phase determination process, which reduces cost and power consumption.