Radio Receiver Interference Suppression via Channel Estimation

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Solution Overview

Problem

Existing radio communication systems face challenges in effectively suppressing interference from different radio systems when sharing a frequency band, as current technologies are limited in their ability to handle interference between systems using distinct communication schemes.

Innovation Solution

A radio reception device and method that estimate and suppress interfering wave components from a first radio system using different communication schemes by generating channel estimate values for both desired and interfering waves, allowing for effective interference suppression even when the systems have different demodulation parameters.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If a frequency band assigned to a first radio system is shared by a second radio system using a different communication scheme, then frequency resource utilization is improved, but interference from the first radio system to the second radio system increases

Engineering Contradiction:

Improvefrequency resource utilizationVSAvoidinterference from first radio system

Core Design Contradiction:

ProductivityVSObject-affected harmful factors

Solution Approach 1:

The patent converts the harmful interference from the first radio system into useful information by estimating the channel characteristics of the interfering waves. The interference signal is no longer treated as pure noise but as a measurable signal that can be characterized and suppressed through channel estimation using correlation processing with known pilot codes from the first radio system.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The patent segments the received signal into desired wave components and interfering wave components through separate channel estimation processes. By independently estimating the channel characteristics of both the second radio system's desired signals and the first radio system's interfering signals, the receiver can separately process and suppress the interference while preserving the desired signal.

Inventive Principle:

Principle #1Segmentation

2Object-affected harmful factors

If transmission power control is used in the second radio system to suppress interference to the first radio system, then interference to the first radio system is reduced, but the separation distance between systems must be short which limits coverage

Engineering Contradiction:

Improveinterference to first radio systemVSAvoidseparation distance

Core Design Contradiction:

Object-affected harmful factorsVSLength of moving object

Solution Approach 1:

Instead of only controlling the transmitter of the second radio system to limit interference, the patent inverts the approach by focusing interference suppression at the receiver end. The receiver estimates and suppresses interfering waves from the first radio system, allowing the transmitter to operate at higher power without causing excessive interference, thereby extending coverage distance.

Inventive Principle:

Principle #13The other way round (Inversion)

3Object-affected harmful factors

If existing interference suppression technologies are used, then interference from the same communication scheme is suppressed, but interference from different communication schemes cannot be effectively suppressed

Engineering Contradiction:

Improveinterference suppressionVSAvoidcompatibility with different communication schemes

Core Design Contradiction:

Object-affected harmful factorsVSAdaptability or versatility

Solution Approach 1:

The patent creates a universal interference suppression mechanism that works across different communication schemes. By using correlation processing with known pilot codes from the first radio system and estimating channel characteristics independently of the specific modulation or coding schemes, the system can suppress interference from any radio system that uses different communication parameters, making the solution broadly applicable.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Data Source

PatentUS9407299B2Radio reception device and radio reception method in radio communication system

Publication Date: 2016.08.02 NEC CORP

AI summary

A radio reception device and a radio receiving method are provided that, when a frequency band assigned to a different radio system is shared, can effectively suppress the influence of interfering waves from this different radio system. A radio reception device is one in a second radio system (11) that can use a frequency band assigned to a first radio system (10), and includes: a desired wave channel estimation section (110) that generates, based on reception signals, first channel estimate values (Es) of interfering wave components arriving from the first radio system, which uses a different communication scheme from that of the second radio system; an interfering wave channel estimation section (120) that generates, based on the reception signals, second channel estimate values (Ei) of desired wave components received through the communication scheme of the second radio system; and an equalization section (105) that suppresses the interfering wave components by using the first and second channel estimate values.