METHOD AND SYSTEM FOR TRANSMISSION AND/OR RECEPTION OF SIGNALS UTILIZING A DELAY CIRCUIT AND DDFS

• US 20090080541A1
• Filed: 09/24/2007
• Published: 03/26/2009
• Est. Priority Date: 09/24/2007
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Rofougaran, Ahmadreza
• Granted Patent: US 8,059,706 B2
• Time in Patent Office: Days
• US Class Current: 375/259
• CPC Class Codes: H04B 1/403 using the same oscillator for generating both the transmitter frequency and the receiver local oscillator frequency

Abstract

Aspects of a method and system for transmission and/or reception of signals utilizing a delay circuit and a DDFS are provided. In this regard, a first signal may be delayed by 90°, via a plurality of delay elements and variable capacitance, to generate a second signal. The first and second signal may be mixed to generate a first LO signal, which may be utilized for a first frequency conversion. A second LO signal may be generated via a DDFS and may be utilized for a second frequency conversion. A digital input word of the DDFS, a value of the variable capacitance, and/or at least a portion of the delay elements, may be programmatically controlled based on a desired frequency for transmission and/or desired frequency for reception. The first frequency conversions may be up-conversions and/or down-conversions to/from baseband, one or more intermediate frequencies, and/or RF.

Claims

1. A method for wireless communication, the method comprising:

delaying a first signal to generate a second signal which is 90°

phase shifted relative to the first signal, wherein said delaying is performed via at least a portion of a plurality of delay elements and a variable capacitance;

mixing said first signal and said second signal to generate a first local oscillator signal that is twice a frequency of said first signal, wherein said first local oscillator signal is utilized for a first frequency conversion; and

generating a second local oscillator signal via a direct digital frequency synthesizer, wherein said second local oscillator signal is utilized for a second frequency conversion.

2. The method according to claim 1, comprising up-converting a baseband signal to an intermediate frequency signal utilizing said first local oscillator signal.

3. The method according to claim 2, comprising up-converting said intermediate frequency to a radio frequency suitable for transmission utilizing said second local oscillator signal.

4. The method according to claim 1, comprising up-converting a first intermediate frequency to a second intermediate frequency utilizing said first local oscillator signal.

5. The method according to claim 1, comprising down-converting a received signal to an intermediate frequency utilizing said second local oscillator signal.

6. The method according to claim 5, comprising down-converting said intermediate frequency to baseband utilizing said first local oscillator signal.

7. The method according to claim 1, comprising down-converting a first intermediate frequency to a second intermediate frequency utilizing said first local oscillator signal.

8. The method according to claim 1, comprising programmably controlling a digital input word of said direct digital frequency synthesizer based on a desired frequency for transmission and/or desired frequency for reception.

9. The method according to claim 1, comprising programmably controlling said at least a portion of said plurality of delay elements based on a desired frequency for transmission and/or desired frequency for reception.

10. The method according to claim 1, comprising programmably controlling said variable capacitance based on a desired frequency for transmission and/or desired frequency for reception.

11. A system for wireless communication, the system comprising:

one or more circuits that delay a first signal to generate a second signal which is 90°

phase shifted relative to the first signal, wherein said delaying is performed via at least a portion of a plurality of delay elements and a variable capacitance;

said one or more circuits mix said first signal and said second signal to generate a first local oscillator signal that is twice a frequency of said first signal, wherein said first local oscillator signal is utilized for a first frequency conversion; and

said one or more circuits comprise a direct digital frequency synthesizer, and said one or more circuits generate a second local oscillator signal via said direct digital frequency synthesizer, wherein said second local oscillator signal is utilized for a second frequency conversion.

12. The system according to claim 11, wherein said one or more circuits enable up-conversion of a baseband signal to an intermediate frequency utilizing said first local oscillator signal.

13. The system according to claim 12, wherein said one or more circuits enable up-conversion of said intermediate frequency to a radio frequency suitable for transmission utilizing said second local oscillator signal.

14. The system according to claim 11, wherein said one or more circuits enable up-conversion of a first intermediate frequency to a second intermediate frequency utilizing said first local oscillator signal.

15. The system according to claim 11, wherein said one or more circuits enable down-conversion of a received signal to an intermediate frequency utilizing said second local oscillator signal.

16. The system according to claim 15, wherein said one or more circuits enable down-converting said intermediate frequency to baseband utilizing said first local oscillator signal.

17. The system according to claim 11, wherein said one or more circuits enable down-conversion of a first intermediate frequency to a second intermediate frequency utilizing said first local oscillator signal.

18. The system according to claim 11, wherein said one or more circuits enable programmatic control of a digital input word of said direct digital frequency synthesizer based on a desired frequency for transmission and/or desired frequency for reception.

19. The system according to claim 11, wherein said one or more circuits enable programmatic control of said at least a portion of said plurality of delay elements based on a desired frequency for transmission and/or desired frequency for reception.

20. The system according to claim 11, wherein said one or more circuits enable programmatic control of said variable capacitance based on a desired frequency for transmission and/or desired frequency for reception.