Method and system for transmission or reception of FM signals utilizing a DDFS clocked by an RFID PLL
View Patent ↗Aspects of a method and system for transmission or reception of FM signals utilizing a DDFS clocked by an RFID PLL are provided. In this regard, one or more signals utilized to transmit or receive FM communication may be generated by clocking a DDFS via a signal generated to enable RFID communication. The DDFS may be controlled via a control word from a processor. In this regard, the control word may determine a frequency and/or phase of the signals output by the DDFS. The control word may be switched between two or more values to generate different frequencies and/or phases in different time intervals. Additionally, the control word may be adjusted to maintain a constant phase and/or frequency in spite of changes to the signal clocking the DDFS.
1. A method for signal processing, the method comprising:
generating a first signal to enable transmission and reception of radio frequency identification (RFID) signals via a single antenna; and
clocking a direct digital frequency synthesizer (DDFS) via said generated first signal to generate a plurality of signals, wherein:
for transmission via said single antenna, said plurality of generated signals are modulated by audio information to generate a frequency modulated (FM) signal;
for reception via said single antenna, said plurality of generated signals are utilized to demodulate an FM signal modulated by audio information; and
a control word input to said DDFS is switched between two values to simulate said transmission and said reception occurring simultaneously.
2. The method according to claim 1 , comprising generating a control word input to said DDFS that controls a frequency of said plurality of signals generated by said DDFS.
3. The method according to claim 1 , comprising switching said control word input to said DDFS between two values in successive time intervals to perform time-division duplexing of FM transmission and FM reception.
4. The method according to claim 3 , wherein said FM transmission occurs at a first frequency and said FM reception occurs at a second frequency.
5. The method according to claim 1 , comprising adjusting a control word input to said DDFS, which controls a frequency of said plurality of signals generated by said DDFS, in response to changes in a frequency of said first signal.
6. The method according to claim 1 , wherein a frequency of said first signal is within one of the following frequency bands: 868 MHz to 928 MHz, 2.4 GHz to 2.483 GHz, and 5.725 to 5.875 GHz.
7. The method according to claim 1 , wherein a frequency of each of said generated plurality of signals is within a frequency band of 60 MHz to 130 MHz.
8. The method according to claim 1 , wherein each of said generated plurality of signals comprise an in-phase component and a quadrature-phase component.
9. The method according to claim 1 , comprising generating said first signal via a phase locked loop.
10. The method according to claim 9 , wherein said phase locked loop operates at a fixed frequency.
11. A system for signal processing, the system comprising:
one or more circuits that generate a first signal to enable transmission and reception of radio frequency identification (RFID) signals via a single antenna; and
said one or more circuits clocks a direct digital frequency synthesizer (DDFS) via said generated first signal to generate a plurality of signals, wherein:
for transmission via said single antenna, said a plurality of generated signals is modulated by audio information to generate a frequency modulated (FM) signal; or
for reception via said single antenna, said a plurality of generated signals are utilized to demodulate an FM signal modulated by audio information; and
a control word input to said DDFS is switched between two values to simulate said transmission and said reception occurring simultaneously.
12. The system according to claim 11 , wherein said one or more circuits generate a control word input to said DDFS that controls a frequency of said a plurality of signals generated by said DDFS.
13. The system according to claim 10 , wherein said one or more circuits switches said control word input to said DDFS between two values in successive time intervals to perform time-division duplexing of FM transmission and FM reception.
14. The system according to claim 13 , wherein said FM transmission occurs at a first frequency and said FM reception occurs at a second frequency.
15. The system according to claim 11 , wherein said one or more circuits adjusts a control word input to said DDFS, which controls a frequency of said a plurality of signals generated by said DDFS, in response to changes in a frequency of said first signal.
16. The system according to claim 11 , wherein a frequency of said first signal is within one of the following frequency bands: 868 MHz to 928 MHz, 2.4 GHz to 2.483 GHz, and 5.725 to 5.875 GHz.
17. The system according to claim 11 , wherein a frequency of each of said generated a plurality of signals is within a frequency band of 60 MHz to 130 MHz.
18. The system according to claim 11 , wherein each of said generated a plurality of signals comprise an in phase component and a quadrature component.
19. The system according to claim 11 , wherein said one or more circuits comprise a phase locked loop that generates said first signal.
20. The system according to claim 19 , wherein said phase locked loop operates at a fixed frequency.