Repeater with digital channelizer

• US 6,873,823 B2
• Filed: 06/20/2002
• Issued: 03/29/2005
• Est. Priority Date: 06/20/2002
• Status: Expired due to Term

• Current Assignee: Axell Wireless Limited (Cobham PLC)
• Original Assignee: Dekolink Wireless Ltd. (Cobham PLC)
• Inventors: Baber, Alex, Hasarchi, Abraham
• Primary Examiner(s): Maung, Nay
• Assistant Examiner(s): Orgad, Edan
• Application Number:
  US10/175,146
• Publication Number:
  US 20030236067A1
• Time in Patent Office: 1,013 Days
• Field of Search: 455/11.1, 455 17- 23, 455/119, 455/67.13, 455/67.11, 455/306, 455/307, 375348-350
• US Class Current: 455/11.1
• CPC Class Codes: H03H 17/0294 Variable filters; Programmable filters
• CPC Class Codes: H04B 1/001 Channel filtering, i.e. selecting a frequency channel within the SDR system multiplexing of multicarrier modulation signals being represented by different frequencies H04L5/06; multiplexing of multicarrier modulation signals H04L5/023
• CPC Class Codes: H04B 1/109 by improving strong signal performance of the receiver when strong unwanted signals are present at the receiver input
• CPC Class Codes: H04B 7/15542 Selecting at relay station its transmit and receive resources selection of wireless resources by user or terminal H04W72/02; arrangements affording multiple use of the transmission path by two-dimensional division of the resources H04L5/0003, or by allocating sub-channels H04L5/003

Abstract

In order to retransmit a communication channel at a specific frequency, a receiver may receive a signal including the communication channel'"'"'s specific frequency. An analog to digital converter may generate a digital signal correlated to the received signal and the digital signal may be passed through a digital filter configured to filter the digital signal and pass frequency components at or around the frequency of the communication channel'"'"'s specific frequency. A digital to analog converter may generate an analog signal correlated to the filtered digital signal and a transmitter may transmit the analog signal.

Claims

1. A method of retransmitting a communication channel comprising:

receiving a signal having a frequency within a frequency range of the communication channel;

generating a digital signal correlated to the received signal;

filtering the digital signal with a digital filter bank configured to pass a plurality of frequency components within said frequency range, wherein said digital filter bank is able to generate a separate and distinct transfer function for each of at least some of said frequency components;

generating an analog signal correlated to the filtered digital signal; and

transmitting the analog signal correlated to the filtered digital signal.

2. The method according to claim 1, further comprising down-converting the received signal to an intermediate frequency prior to generating a digital signal.

3. The method according to claim 2, further comprising up-converting the analog signal correlated to the filtered digital signal prior to transmitting the analog signal.

4. A method of retransmitting a communication channel comprising:

receiving a signal having a frequency within a frequency range of the communication channel;

generating a digital signal correlated to the received signal;

filtering the digital signal with a digital filter bank configured to pass a plurality of frequency components within said frequency range, wherein said digital filter bank is able to generate a separate and distinct transfer function for each of at least some of said frequency components;

generating an analog signal correlated to the filtered digital signal;

transmitting the analog signal correlated to the filtered digital signal; and

filtering the digital signal with a second digital filter bank configured to pass a plurality of frequency components within a second frequency range, associated with a second communication channel, wherein said digital filter bank is able to generate a separate and distinct transfer function for each of at least some of said frequency components.

5. The method according to claim 4, further comprising combining the digital signals out from each of said filtering steps and generating an analog signal correlated to the combined digital signal.

6. The method according to claim 5, further comprising transmitting the analog signal correlated to the combined digital signal.

7. A system for retransmitting a communication channel within a predetermined frequency range, said system comprising:

a receiver to receive a signal having a frequency within the frequency range of the communication channel;

an analog to digital converter to generate a digital signal correlated to the received signal;

a digital filter bank configured to filter the digital signal by passing a plurality of frequency components within said frequency range, wherein said digital filter bank is able to generate a separate and distinct frequency transfer function for each of at least some of said frequency components;

a digital to analog converter to generate an analog signal correlated to the filtered digital signal; and

a transmitter to transmit the analog signal correlated to the filtered digital signal.

8. The system according to claim 7, further comprising a down converter to convert the received signal to an intermediate frequency.

9. The system according to claim 8, further comprising an up converter to convert the analog signal correlated to the filtered digital signal to a transmission frequency.

10. The system according to claim 7, further comprising a second digital filter bank configured to pass a plurality of frequency components within a second frequency range, wherein said digital filter bank is able to generate a separate and distinct transfer function for each of at least some of said frequency components associated with a second communication channel.

11. The system according to claim 10, further comprising a summing unit to combine outputs from said first and second digital filters.

12. The system according to claim 7, wherein said digital filter bank is configured to notch out narrow band noise interference within a frequency band of said communication channel.

13. A system for retransmitting a communication channel within a predetermined frequency range, said system comprising:

a receiver to receive a signal having a frequency within the frequency range of the communication channel;

an analog to digital converter to generate a digital signal correlated to the received signal;

a field programmable digital filter bank configured to filter the digital signal by passing a plurality of frequency components within said frequency range, wherein said digital filter bank is able to generate a separate and distinct transfer function for each of at least some of said frequency components;

a digital to analog converter to generate an analog signal correlated to the filtered digital signal; and

a transmitter to transmit the analog signal correlated to the filtered digital signal.

14. The system according to claim 13, wherein said field programmable digital filter bank is locally controllable.

15. The system according to claim 13, wherein said digital filter is remotely controllable.

16. The system according to claim 13, wherein said filter bank is able to choose an optimal transfer function for each of said plurality of frequency components.

17. A system for retransmitting a communication channel within a predetermined frequency range, said system comprising:

a receiver to receive a signal having a frequency within the frequency range of the communication channel;

a first gain control unit to adjust said signal to produce an input signal;

an analog to digital converter to generate a digital signal correlated to the input signal;

a digital filter bank configured to filter the digital signal by passing a plurality of frequency components within said frequency range, wherein said digital filter bank is able to generate a separate and distinct transfer function for each of at least some of said frequency components;

a digital to analog converter to generate an analog signal correlated to the filtered digital signal;

a second gain control unit to adjust said analog signal to produce a desired output signal; and

a transmitter to transmit the output signal correlated to the filtered digital signal.

18. The system according to claim 17, wherein said second gain control unit comprises a variable gain amplifier.

19. The system according to claim 17, wherein said digital bank is further configured to filter the digital signal by passing a plurality of frequency components within said frequency range, wherein said digital filter bank is able to generate a separate and distinct filter gain for each of at least some of said frequency components.