UWB communication receiver feedback loop

Abstract

A novel technique and structure that maximizes the extraction of information from reference pulses for UWB-TR receivers is introduced. The scheme efficiently processes an incoming signal to suppress different types of UWB as well as non-UWB interference prior to signal detection. Such a method and system adds a feedback loop mechanism to enhance the signal-to-noise ratio of reference pulses in a conventional TR receiver. Moreover, sampling the second order statistical function such as, for example, the autocorrelation function (ACF) of the received signal and matching it to the ACF samples of the original pulses for each transmitted bit provides a more robust UWB communications method and system in the presence of channel distortions.

Description

RELATED APPLICATION [0001] This application is a continuation of prior application Ser. No. 10 / 815,450 filed Mar. 31, 2004, entitled “UWB Communications Receiver Feedback Loop”, which claims the benefit of U.S. Provisional Application No. 60 / 474,150, filed May 28, 2003, and entitled, “Impulse Communications”, both of which are incorporated herein by this reference. Any disclaimer that may have occurred during the prosecution of the above-referenced application Ser. No. 10 / 815,450 is hereby expressly rescinded.[0002] The United States Government has rights in this invention pursuant to Contract No. W-7405-ENG-48 between the United States Department of Energy and the University of California for the operation of Lawrence Livermore National Laboratory.BACKGROUND OF THE INVENTION [0003] 1. Field of the Invention [0004] The present invention relates to a communication method, apparatus and system, and more particularly to an ultra wide-band (UWB) communication apparatus, system and metho...

AI Technical Summary

Benefits of technology

"The present invention is about an ultra-wideband (UWB) receiver system and method that uses a feedback loop mechanism to enhance the signal-to-noise ratio of reference pulses in a conventional TR receiver. The system and method also correlates and multi-samples received pulses over values indicative of a second order statistical function from transmitted pulse pairs. Additionally, the system and method utilizes the feedback loop mechanism to enhance the signal-to-noise ratio of reference pulses in addition to correlating and multi-sampling received pulses over values indicative of the autocorrelation function to determine an output signal that indicates encoded information. The technical effects of the invention are a more robust and increased signal-to-noise ratio, suppression of AWGN and NBI, and added security for multiple users to communicate in a covert communication system for military applications."

Problems solved by technology

Although UWB communications offer a promising solution to an increasingly overcrowded frequency spectrum, the overlay of UWB signals on coexisting narrowband systems can impart interference, i.e., noise, for both UWB and narrowband systems.

However, strong interference from narrowband systems on UWB devices can be detrimental to low powered UWB waveforms and is not to be overlooked.

Conventional ultra wideband TR receivers perform poorly in low-signal-to-noise-ratio environments due to an increase in the received signal's noise-on-noise component introduced by various types of channel noise, such as, AWGN or narrowband interference (NBI) on the transmitted signal.

Therefore, such receivers are essentially ineffective for covert, low probability of intercept and detection (LPI / D) communication systems where low power UWB signals have to overcome the effect of intentional and non-intentional jamming by narrowband signals.

Moreover, since conventional TR receivers use the same pulse shape for several users in a multiple access channel, the correlation between similar pulses increases the multiple access interference (MAI) as the number of users increases.

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