Receiver For Use In An Ultra-Wideband Communication System

• US 20130163638A1
• Filed: 02/25/2013
• Published: 06/27/2013
• Est. Priority Date: 03/22/2010
• Status: Active Grant

• Current Assignee: DecaWave Limited (Qorvo, Inc.)
• Original Assignee: DecaWave Limited (Qorvo, Inc.)
• Inventors: McLaughlin, Michael, McElroy, Ciaran, Wilmot, Sinbad, Proudfoot, Tony
• Granted Patent: US 8,760,334 B2
• Time in Patent Office: Days
• US Class Current: 375/130
• CPC Class Codes: G06F 17/15 Correlation function computation including computation of convolution operations arithmetic circuits for sum of products per se, e.g. multiply-accumulators G06F7/5443; digital filters, e.g. FIR, IIR, adaptive filters H03H17/00
• CPC Class Codes: H03D 3/00 Demodulation of angle-, frequency- or phase- modulated oscillations H03D5/00, H03D9/00, H03D11/00 take precedence
• CPC Class Codes: H04B 1/7073 Synchronisation aspects
• CPC Class Codes: H04B 1/709 Correlator structure
• CPC Class Codes: H04B 1/7097 Interference-related aspects
• CPC Class Codes: H04B 1/71637 Receiver aspects H04B1/7183 takes precedence
• CPC Class Codes: H04L 27/38 Demodulator circuits; Receiver circuits

Abstract

In an ultra-wideband (“UWB”) receiver, a received UWB signal is periodically digitized as a series of ternary samples. The samples are continuously correlated with a predetermined preamble sequence to develop a correlation value. When the value exceeds a predetermined threshold, indicating that the preamble sequence is being received, estimates of the channel impulse response (“CIR”) are developed. When a start-of-frame delimiter (“SFD”) is detected, the best CIR estimate is provided to a channel matched filter (“CMF”) substantially to filter channel-injected noise.

Claims

1. Apparatus for use in an ultra-wideband (UWB) communication system in which multi-symbol packets are transmitted via a transmission channel, each transmitted packet comprising a multi-symbol data payload, the apparatus comprising:

an analog-to-digital converter (ADC) adapted to;

receive a conditioned form of a received packet;

periodically sample said packet at a selected over-sample rate; and

provide corresponding samples, each sample comprising a selected one of;

a sign bit having a first value indicative of said sample being positive, and a second value indicative of said sample being negative;

or

a single trit having a first value indicative of said sample being positive, a second value indicative of said sample being substantially zero, and a third value indicative of said sample being negative;

or

a sign bit and a magnitude bit;

said sign bit having a first value indicative of said sample being positive, and a second value indicative of said sample being negative; and

said magnitude bit having a first value indicative of said sample being substantially zero, and a second value indicative of said sample being substantially non-zero; and

a digital channel matched filter adapted to receive a selected set of the samples, and to develop therefrom a multi-value result vector as a function of a best estimate of a channel impulse response (CIR) of said channel, the CIR estimate comprising a set of coefficients.

2. The apparatus of claim 1 wherein the channel matched filter further comprises:

a digital delay line adapted to;

serially receive the samples;

store a selected set of the received samples; and

provide the stored samples;

a digital CIR estimate store adapted to;

receive the coefficients comprising the CIR estimate;

store the received coefficients; and

provide the stored coefficients;

a digital multiplier adapted to;

receive the stored samples;

receive the stored coefficients; and

develop a set of partial sums, each as a function of a respective one of the stored samples and a respective one of the stored coefficients; and

a digital summer adapted to;

receive the partial sums; and

develop a respective one of the result vector values as a function of the received partial sums.

3. A receiver for use in an ultra-wideband (UWB) communication system in which multi-symbol packets are transmitted via a transmission channel, each transmitted packet comprising a multi-symbol data payload, the receiver comprising:

an analog-to-digital converter (ADC) adapted to;

receive a conditioned form of a received packet;

periodically sample said packet at a selected over-sample rate; and

provide corresponding samples, each sample comprising a selected one of;

a sign bit having a first value indicative of said sample being positive, and a second value indicative of said sample being negative;

or

a single trit having a first value indicative of said sample being positive, a second value indicative of said sample being substantially zero, and a third value indicative of said sample being negative;

or

a sign bit and a magnitude bit;

said sign bit having a first value indicative of said sample being positive, and a second value indicative of said sample being negative; and

said magnitude bit having a first value indicative of said sample being substantially zero, and a second value indicative of said sample being substantially non-zero; and

a digital channel matched filter adapted to receive a selected set of the samples, and to develop therefrom a multi-value result vector as a function of a best estimate of a channel impulse response (CIR) of said channel, the CIR estimate comprising a set of coefficients.

4. The apparatus of claim 3 wherein the channel matched filter further comprises:

a digital delay line adapted to;

serially receive the samples;

store a selected set of the received samples; and

provide the stored samples;

a digital CIR estimate store adapted to;

receive the coefficients comprising the CIR estimate;

store the received coefficients; and

provide the stored coefficients;

a digital multiplier adapted to;

receive the stored samples;

receive the stored coefficients; and

develop a set of partial sums, each as a function of a respective one of the stored samples and a respective one of the stored coefficients; and

a digital summer adapted to;

receive the partial sums; and

develop a respective one of the result vector values as a function of the received partial sums.

5. A method for operating an ultra-wideband (UWB) communication system in which multi-symbol packets are transmitted via a transmission channel, each transmitted packet comprising a multi-symbol data payload, the method comprising the steps of:

analog-to-digital converting each transmitted packet by;

receiving a conditioned form of a received packet;

periodically sampling said packet at a selected over-sample rate; and

providing corresponding samples, each sample comprising a selected one of;

a sign bit having a first value indicative of said sample being positive, and a second value indicative of said sample being negative;

or

a single trit having a first value indicative of said sample being positive, a second value indicative of said sample being substantially zero, and a third value indicative of said sample being negative;

or

a sign bit and a magnitude bit;

said sign bit having a first value indicative of said sample being positive, and a second value indicative of said sample being negative; and

said magnitude bit having a first value indicative of said sample being substantially zero, and a second value indicative of said sample being substantially non-zero; and

digitally channel match filtering a selected set of the samples, and developing therefrom a multi-value result vector as a function of a best estimate of a channel impulse response (CIR) of said channel, the CIR estimate comprising a set of coefficients.

6. The method of claim 5 wherein the method further comprises the steps of:

serially receiving the samples, storing a selected set of the received samples, and providing the stored samples;

receiving the coefficients comprising the CIR estimates, storing the received coefficients, and providing the stored coefficients;

receiving the stored samples and the stored coefficients, and developing a set of partial sums, each as a function of a respective one of the stored samples and a respective one of the stored coefficients; and

receiving the partial sums, and developing a respective one of the result vector values as a function of the received partial sums.