Configurable acquisition engine for receiver of spread spectrum signals
AssigneeRaytheon Company
InventorsPhillip M. Izdebski, Gennady Y. Poberezhskiy, Matthew C. Dusard
Life of this patent
Estimating the term…
Abstract
A configurable acquisition engine for direct sequence (DS) spread spectrum (SS) is provided that is reconfigurable without increasing memory size for several use cases having different time-frequency uncertainties. The acquisition engine utilizes a frequency-domain decimation filter to reduce the number of output frequency points while still utilizing information from all frequency bins.
Claims20
A configurable direct sequence (DS) spread spectrum (SS) electronic device including:
- a fast Fourier transform (FFT) module configured to:
- receive an input signal;
- compute an FFT of the input signal;
- output n bins of frequency data having an initial frequency spacing, wherein n is an integer greater than 1, and wherein each of the n bins:
- corresponds to a range of frequencies matching the initial frequency spacing;
- and
- includes a magnitude of a complex-valued FFT output for the bin;
- a frequency-domain decimation filter configured to:
- utilize m bins of the n bins of frequency data from the FFT module having the initial frequency spacing, wherein m is an integer greater than 1;
- and
- output q bins of the n bins of frequency data having a larger frequency spacing, wherein q is an integer greater than 1, and wherein q<m;
- and
- memory configured to receive and store a portion of the n bins of frequency data.
A configurable direct sequence (DS) spread spectrum (SS) electronic device including:
- a fast Fourier transform (FFT) module configured to:
- receive an input signal;
- compute an FFT of the input signal;
- output n bins of frequency data having an initial frequency spacing, wherein n is an integer greater than 1, and wherein each of the n bins:
- corresponds to a range of frequencies matching the initial frequency spacing;
- and
- includes a magnitude value based on an amplitude of frequencies of the FFT in the range of frequencies;
- memory configured to receive and store a portion of the n bins of frequency data;
- and
- circuitry configured to:
- receive a mode of operation;
- when the mode of operation is a first mode:
- pass r bins of the n bins of frequency data from the FFT to the memory, wherein r is an integer greater than 1;
- and
- cause the memory to store the r bins of frequency data as said portion;
- when the mode of operation is a second mode:
- pass s bins of the n bins of frequency data from the FFT to the memory, wherein s is an integer greater than 1, and wherein s is less than r;
- and
- cause the memory to store the s bins of frequency data as said portion;
- and
- when the mode of operation is a third mode:
- pass the m bins of the n bins of frequency data from the FFT to a frequency-domain decimation filter, wherein m is an integer greater than 1;
- and
- cause the memory to store q bins of the n bins of frequency data as said portion, wherein q is an integer greater than 1.
A method of processing an input signal using a configurable direct sequence (DS) spread spectrum (SS) electronic device, the method comprising;
- receiving the input signal;
- correlating the input signal to produce a correlated input signal;
- computing a fast Fourier transform (FFT) of the correlated input signal using an FFT module;
- outputting from the FFT module n bins of frequency data having an initial frequency spacing, wherein n is an integer greater than 1, and wherein each of the n bins:
- corresponds to a range of frequencies matching the initial frequency spacing;
- and
- includes a magnitude value based on an amplitude of frequencies of the FFT in the range of frequencies;
- receiving with a frequency-domain decimation filter m bins of the n bins of frequency data from the FFT module having the initial frequency spacing, wherein m is an integer greater than 1;
- outputting from the frequency-domain decimation filter q bins of frequency data having a larger frequency spacing, wherein q is an integer greater than 1, and wherein q<m;
- and
- storing a portion of the n bins of frequency data in memory.
Dependencies are inferred from the claim text.