Dynamic matched filter bank and its application in multi-channel spread spectrum communication systems

• US 20040008759A1
• Filed: 07/11/2002
• Published: 01/15/2004
• Est. Priority Date: 07/11/2002
• Status: Active Grant

• Current Assignee: George L. Yang
• Original Assignee: George L. Yang
• Inventors: Yang, George L.
• Granted Patent: US 7,317,753 B2
• Time in Patent Office: Days
• US Class Current: 375/152
• CPC Class Codes: H04B 1/7093 Matched filter type
• CPC Class Codes: H04B 2001/70935 using a bank of matched fileters, e.g. Fast Hadamard Transform
• CPC Class Codes: H04B 2201/7071 with dynamic control of receiver resources

Abstract

A dynamic matched filter bank consists of a plurality of matched filters with either the reference signal for each matched filter changes with the time or the input signal to a matched filter is the received signal modified by a different way for a different matched filter. A receiver employed a set of dynamic matched filter banks in a multi-channel spread spectrum communication system consists of a signal register, a block PN generator, a plurality of spreading sequence generators, a plurality of register arrays, a plurality of multiplier arrays, a plurality of matched filters, a plurality of signal combiners, and a controller. The block PN generator generates a section of PN sequence at the end of every symbol period with feedback logic to shift a block of chips each time. A register array captures each section of PN sequence from the block PN generator and delays it for a symbol period. The rest register arrays are in cascade and delay the section of sequence at each of their inputs by one symbol period. The signal register generates a moving section of the received signal. Each of the multiplier arrays multiplies each moving section of the received signal by a section of PN sequence from either the block PN generator or one of the register arrays to provide a input signal to a corresponding matched filter. Each of the matched filter is to find the correlation between the section of its input signal and the section of its reference signal, which is a spreading sequence from a corresponding spreading sequence generator. Each of the signal combiners will combine the components from corresponding matched filters. The controller will monitor the signals from all matched filters and all signal combiners, extract necessary information, and generate various control signals.

Claims

1. A subsystem for detecting, tracking, and combining the components of a multipath fading signal spanned over several symbol periods, comprising:

a signal register, receiving a input signal, for generating a section of the input signal, which is a moving section of sampled version of the input signal with the delay between any two adjacent samples being equal;

a block reference signal generator for generating a section of a reference signal and holding the section for a certain amount of time, then generating another section of the reference signal, with the second section being immediately after the first section and the lengths of two sections being equal, and holding the new section for same amount of time, and repeating the process; and

a plurality of matched filters, wherein each matched filter is for finding the correlation between a section of the input signal and a section of the matched-filter specific reference signal for the matched filter.

2. A subsystem for detecting, tracking, and combining the components of a multipath fading signal spanned over several symbol periods as in claim 1, wherein a section of a reference signal is a set of sampled values of the reference signal in one symbol period and wherein a certain amount of time is one symbol interval.

3. A subsystem for detecting, tracking, and combining the components of a multipath fading signal spanned over several symbol periods as in claim 1, wherein a section of the matched-filter specific reference signal for the matched filter is a section of the signal selected from the group consisting of the reference signal and its varied versions with one to plurality symbol delays.

4. A subsystem for detecting, tracking, and combining the components of a multipath fading signal spanned over several symbol periods as in claim 1, wherein a block reference signal generator is a linear feedback shift register with a feedback logic to shift a plurality of chips at one time.

5. A subsystem for detecting, tracking, and combining the components of a multipath fading signal spanned over several symbol periods as in claim 1, further comprising a plurality of register arrays, one of which is coupled to the block reference signal generator with each of the rest coupled to its previous register array, wherein each register array is for delaying the section of the signal at its input by a symbol period and providing a corresponding matched filter a section of the matched-filter specific reference signal.

6. A subsystem for detecting, tracking, and combining the components of a multipath fading signal spanned over several symbol periods as in claim 5, further comprising:

a controller, receiving signals from all the matched filters and all the signal combiners, for extracting and generating various control signals; and

a plurality of signal combiners, wherein a respective signal combiner is coupled to a plurality of matched filters, each signal combiner for combining the components of a multipath signal.

7. A subsystem for detecting, tracking, and combining the components of a multipath fading signal spanned over several symbol periods as in claim 1, further comprising a plurality of register arrays, each of which is coupled to the block reference signal generator, wherein each register array is for capturing the section of the reference signal at different time, holding the section by a plurality of symbol periods, and providing a corresponding matched filter a section of the matched-filter specific reference signal.

8. A subsystem for detecting, tracking, and combining the components of a multipath fading signal spanned over several symbol periods as in claim 7, further comprising:

a controller, receiving signals from all the matched filters and all the signal combiners, for extracting information and generating various control signals; and

a plurality of signal combiners, wherein a respective signal combiner is coupled to a corresponding matched filter, each signal combiner for combining the components of a multipath signal.

9. A subsystem for detecting, tracking, and combining the components of a multipath fading signal spanned over several symbol periods, comprising:

a signal register, receiving a input signal, for generating a section of the input signal, which is a moving section of sampled version of the input signal with the delay between any two adjacent samples being equal;

a first component reference signal generator for generating a section of a first component reference signal and holding the section for a certain amount of time, then generating another section of the first component reference signal, with the second section being immediately after the first section and the lengths of two sections being equal, and holding the new section for same amount of time, and repeating the process;

a second component reference signal generator for generating a section of a second component reference signal; and

a plurality of matched filters, wherein each matched filter is for finding the correlation between a section of the matched-filter specific input signal to the matched filter and a section of the matched-filter specific reference signal for the matched filter.

10. A subsystem for detecting, tracking, and combining the components of a multipath fading signal spanned over several symbol periods as in claim 9, wherein a section of a first component reference signal is a set of sampled values of the first component reference signal in one symbol period and wherein a certain amount of time is one symbol interval.

11. A subsystem for detecting, tracking, and combining the components of a multipath fading signal spanned over several symbol periods as in claim 9, wherein a first component reference signal generator is a linear feedback shift register with a feedback logic to shift a plurality of chips at one time.

12. A subsystem for detecting, tracking, and combining the components of a multipath fading signal spanned over several symbol periods as in claim 9, wherein a section of the matched-filter specific reference signal for the matched filter is a section of the second component reference signal.

13. A subsystem for detecting, tracking, and combining the components of a multipath fading signal spanned over several symbol periods as in claim 12, further comprising:

a plurality of register arrays, one of which is coupled to the first component reference signal generator with each of the rest coupled to its previous register array, wherein each register array is for delaying the section of the signal at its input by a symbol period; and

a plurality of multiplier arrays, one of which is coupled to the first component reference signal generator with each of the rest coupled to its corresponding register array, wherein each multiplier array is for multiplying a section of the input signal by a section of signal from a device selected from the group consisting of the first component reference signal generator and a plurality of register arrays and providing a corresponding matched filter a section of the matched-filter specific input signal.

14. A subsystem for detecting, tracking, and combining the components of a multipath fading signal spanned over several symbol periods as in claim 9, further comprising:

a plurality of register arrays, each of which is coupled to the first component reference signal generator, wherein each register array is for capturing a section of the first component reference signal at different time, holding the section by a same plurality of symbol periods, and providing a corresponding matched filter a section of the matched-filter specific reference signal; and

a multiplier array, coupled to the second component reference signal generator, is for multiplying a section of the input signal by a section of the second component reference signal and providing each matched filter a section of the matched-filter specific input signal.

15. A subsystem for detecting, tracking, and combining the components of a multipath fading signal spanned over several symbol periods in a radio link of a multi-channel spread spectrum communication system, comprising:

a signal register, receiving an input signal, for generating a moving section of the sampled version of input signal;

a first component reference signal generator, with a feedback logic based on shifting a block of chips at end of each symbol period, for generating a section of a first component reference signal and holding the section for one symbol period, then generating another section of the first component reference signal, with the second section being immediately after the first section and the lengths of two sections being equal, and holding the new section for one symbol period, and repeating the process;

a plurality of register arrays, one of which is coupled to the first component reference signal generator with each of the rest coupled to its previous register array, wherein each register array is for capturing the section of the signal at its input and holding the section for one symbol period, then capturing another section of the signal at its input and holding the new section for symbol period, and so on;

a plurality of second component reference signal generators, wherein a respective second component reference signal generator for generating a spreading signal to spread the information on a corresponding channel;

a plurality of matched filters, wherein a respective matched filter for finding the correlation between a section of the matched-filter specific input signal to the matched filter and a section of the matched-filter specific reference signal for the matched filter;

a plurality of signal combiners, wherein a respective signal combiner is coupled to the corresponding matched filters, each signal combiner for combining the components of a multipath signal together; and

a controller, receiving signals from all the matched filters and all the signal combiners, for extracting information and generating various control signals.

16. A subsystem for detecting, tracking, and combining the components of a multipath fading signal spanned over several symbol periods in a radio link of a multi-channel spread spectrum communication system as in claim 15, wherein a section of the matched-filter specific reference signal for the matched filter is a section of signal from a corresponding second component reference signal generator.

17. A subsystem for detecting, tracking, and combining the components of a multipath fading signal spanned over several symbol periods in a radio link of a multi-channel spread spectrum communication system as in claim 16, further comprising a plurality of multiplier arrays, one of which is coupled to the first component reference signal generator with each of the rest coupled to its corresponding register array, wherein each multiplier array is for multiplying a section of the input signal by a section of the signal from a device selected from the group consisting of the first component reference signal generator and a plurality of register arrays and providing a corresponding matched filter a section of the matched-filter specific input signal.

18. A subsystem for detecting, tracking, and combining the components of a multipath fading signal spanned over several symbol periods in a radio link of a multi-channel spread spectrum communication system as in claim 15, wherein a section of the matched-filter specific input signal to the matched filter is a section of the input signal.

19. A subsystem for detecting, tracking, and combining the components of a multipath fading signal spanned over several symbol periods in a radio link of a multi-channel spread spectrum communication system as in claim 18, further comprising a plurality of exclusive-or arrays, one of which is coupled to the first component reference signal generator with each of the rest coupled to its corresponding register array, wherein each exclusive-or array is for exclusive-oring a section of the signal from a device selected from the group consisting of the first component reference signal generator and a plurality of register arrays with a section of the signal from a corresponding second component reference signal generator and providing a corresponding matched filter a section of the matched-filter specific reference signal.