I/Q Receiver Channel Sharing for Image Rejection and Lower Power

Solution Overview

Problem

Low- and intermediate-frequency receiver architectures in wireless communication systems face issues with image interference and increased circuit area and power consumption due to the need for multiple mixers, filters, and analog-to-digital converters.

Innovation Solution

A receiving apparatus that uses a single set of channels for processing in-phase and quadrature signals, employing an image rejection filter and adjusting the down-converted frequency ratio to the switching frequency to reduce power consumption and circuit area.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If two sets of mixers, filters, amplifiers, and analog-to-digital converters are used to process I and Q signals separately, then signal processing reliability is improved, but circuit area and power consumption increase

Engineering Contradiction:

Improvesignal processing reliabilityVSAvoidcircuit area

Core Design Contradiction:

ReliabilityVSArea of stationary object

Solution Approach 1:

The patent merges the processing paths for I and Q signals by using a single set of channels (mixer, filter, amplifier, ADC) to process both signals sequentially through time-division multiplexing, eliminating the need for duplicate hardware components while maintaining signal processing capability

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent implements periodic switching between I and Q signal processing using a selection unit that alternates between the two signals at regular intervals, allowing a single channel to handle both signals in a time-division manner

Inventive Principle:

Principle #19Periodic action

2Reliability

If two sets of mixers, filters, amplifiers, and analog-to-digital converters are used to process I and Q signals separately, then signal processing reliability is improved, but power consumption increases

Engineering Contradiction:

Improvesignal processing reliabilityVSAvoidpower consumption

Core Design Contradiction:

ReliabilityVSUse of energy by stationary object

Solution Approach 1:

The patent merges the processing paths for I and Q signals by using a single set of channels (mixer, filter, amplifier, ADC) to process both signals sequentially through time-division multiplexing, eliminating the need for duplicate hardware components while maintaining signal processing capability

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent implements periodic switching between I and Q signal processing using a selection unit that alternates between the two signals at regular intervals, allowing a single channel to handle both signals in a time-division manner

Inventive Principle:

Principle #19Periodic action

3Object-affected harmful factors

If a low- and intermediate-frequency receiver architecture is used, then image interference is avoided, but circuit complexity increases

Engineering Contradiction:

Improveimage interferenceVSAvoidcircuit complexity

Core Design Contradiction:

Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The patent uses periodic switching between I and Q signals combined with an image rejection filter to eliminate image interference without requiring separate processing channels, reducing circuit complexity while maintaining interference rejection capability

Inventive Principle:

Principle #19Periodic action

Solution Approach 2:

The patent introduces an image rejection filter as an intermediary component that processes the combined I and Q signals to eliminate image interference, avoiding the need for complex separate processing paths

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS9008206B2Receiving apparatus with a single set of channels for processing plural sets of in-phase and quadrature phase signals

Publication Date: 2015.04.14 REALTEK SEMICON CORP

AI summary

The present invention relates to a receiving apparatus of a communication system, which comprises a receiving module, a selection unit, and a processing module. The receiving module receives an input signal and produces a first signal and a second signal. The phases of the first and the second signals are different. The selection unit receives the first and the second signals, and switches for outputting the first or the second signal. The processing module receives and processes the first and the second signals, and produces an output signal. Thereby, the present invention uses the selection unit for processing two phase signals via a set of channels. Thereby, circuit area and power consumption can be reduced, and hence achieving the purpose of saving cost.