Wireless local area network (WLAN) using universal frequency translation technology including multi-phase embodiments and circuit implementations

• US 7,110,444 B1
• Filed: 08/04/2000
• Issued: 09/19/2006
• Est. Priority Date: 08/04/1999
• Status: Expired due to Fees

• Current Assignee: ParkerVision, Inc.
• Original Assignee: ParkerVision, Inc.
• Inventors: Cook, Robert W., Rawlins, Gregory S., Bultman, Michael J., Sorrells, David F., Moses, Charley D. Jr., Looke, Richard C., Rawlins, Michael W.
• Primary Examiner(s): Fan, Chieh M.
• Assistant Examiner(s): Kim, Kevin
• Application Number:
  US09/632,856
• Time in Patent Office: 2,237 Days
• Field of Search: 375/222, 375/328, 375/324, 375/349, 455/131, 455/137, 455/150.1, 455/189.1, 455/190.1, 455/313, 455/323, 455/326
• US Class Current: 375/222
• CPC Class Codes: H03C 3/40 using two signal paths the outputs of which have a predetermined phase difference and at least one output being amplitude-modulated
• CPC Class Codes: H03D 3/006 by sampling the oscillations and further processing the samples, e.g. by computing techniques H03D3/007 takes precedence
• CPC Class Codes: H03D 7/00 Transference of modulation from one carrier to another, e.g. frequency-changing H03D9/00, H03D11/00 take precedence; dielectric amplifiers, magnetic amplifiers, parametric amplifiers used as a frequency-changers H03F
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/02 Terminal devices

Abstract

Frequency translation and applications of the same are described herein, including RF modem and wireless local area network (WLAN) applications. In embodiments, the WLAN invention includes an antenna, an LNA/PA module, a receiver, a transmitter, a control signal generator, a demodulation/modulation facilitation module, and a MAC interface. The WLAN receiver includes at least one universal frequency translation module that frequency down-converts a received EM signal. In embodiments, the UFT based receiver is configured in a multi-phase embodiment to reduce or eliminate re-radiation that is caused by DC offset. The WLAN transmitter includes at least one universal frequency translation module that frequency up-converts a baseband signal in preparation for transmission over the wireless LAN. In embodiments, the UFT based transmitter is configured in a differential and multi-phase embodiment to reduce carrier insertion and spectral growth.

Claims

1. A wireless modem apparatus, comprising:

a receiver for frequency down-converting an input signal including,

a first frequency down-conversion module to down-convert the input signal, wherein said first frequency down-conversion module down-converts said input signal according to a first control signal and outputs a first down-converted signal;

a second frequency down-conversion module to down-convert said input signal, wherein said second frequency down-conversion module down-converts said input signal according to a second control signal and outputs a second down-converted signal; and

a subtractor module that subtracts said second down-converted signal from said first down-converted signal and outputs a down-converted signal;

wherein said second control signal is delayed relative to said first control signal by (0.5+n) cycles of said input signal, wherein n is an integer greater than or equal to 1.

5. The apparatus of claim 1, wherein said subtractor module comprises a differential amplifier.

2. A wireless modem apparatus, comprising:

a receiver for frequency down-converting an input signal including,

a first frequency down-conversion module to down-convert the input signal, wherein said first frequency down-conversion module down-converts said input signal according to a first control signal and outputs a first down-converted signal;

a second frequency down-conversion module to down-convert said input signal, wherein said second frequency down-conversion module down-converts said input signal according to a second control signal and outputs a second down-converted signal; and

a subtractor module that subtracts said second down-converted signal from said first down-converted signal and outputs a down-converted signal;

wherein said first frequency down-conversion module under-samples said input signal according to said first control signal, and said second frequency down-conversion module under-samples said input signal according to said second control signal.

3. A wireless modem apparatus, comprising:

a receiver for frequency down-converting an input signal including,

a first frequency down-conversion module to down-convert the input signal, wherein said first frequency down-conversion module down-converts said input signal according to a first control signal and outputs a first down-converted signal;

a second frequency down-conversion module to down-convert said input signal, wherein said second frequency down-conversion module down-converts said input signal according to a second control signal and outputs a second down-converted signal; and

a subtractor module that subtracts said second down-converted signal from said first down-converted signal and outputs a down-converted signal;

wherein said first and said second frequency down-conversion modules each comprise a switch and a storage element.

4. The apparatus of claim 3, wherein said storage elements comprises a capacitor that reduces a DC offset voltage in said first down-converted signal and said second down-converted signal.

6. A wireless modem apparatus, comprising:

a receiver for frequency down-converting an input signal including,

a first frequency down-conversion module to down-convert the input signal, wherein said first frequency down-conversion module down-converts said input signal according to a first control signal and outputs a first down-converted signal;

a second frequency down-conversion module to down-convert said input signal, wherein said second frequency down-conversion module down-converts said input signal according to a second control signal and outputs a second down-converted signal;

a subtractor module that subtracts said second down-converted signal from said first down-converted signal and outputs a down-converted signal;

a transmitter for up-converting a baseband signal and coupled to said receiver, including,

an inverter, to receive said baseband signal and generate an inverted baseband signal;

a first controlled switch, coupled to a non-inverting output of said inverter, said first controlled switch to sample said baseband signal according to a third control signal, resulting in a first harmonically rich signal;

a second controlled switch, coupled to an inverting output of said inverter, said second controlled switch to sample said inverted baseband signal according to a fourth control signal, resulting in a second harmonically rich signal; and

a combiner, coupled to an output of said first controlled switch and an output of said second controlled switch, said combiner to combine said first harmonically rich signal and said second harmonically rich signal, resulting in a third harmonically rich signal.

7. The apparatus of claim 6, wherein said fourth control signal is phase shifted with respect to said third control signal.

8. The apparatus of claim 6, wherein said fourth control signal is phase shifted by 180 degrees with respect to said third control signal.

9. The apparatus of claim 6, further comprising a filter coupled to an output of said combiner, wherein said filter outputs a desired harmonic from said third harmonically rich signal.

10. The apparatus of claim 6, wherein said apparatus is an infrastructure device.

11. The apparatus of claim 6, wherein said apparatus is a client device.

12. The apparatus of claim 6, wherein said first controlled switch shunts said baseband signal to a reference potential according to said third control signal, and wherein said second controlled switch shunts said inverted baseband signal to said reference potential according to said fourth control signal.

13. The apparatus of claim 6, further comprising an antenna coupled to said transmitter and said receiver.

14. The apparatus of claim 13, further comprising a switch, said switch selectively connecting said transmitter or said receiver to said antenna.

15. The apparatus of claim 6, further comprising a baseband processor coupled to said transmitter and said receiver.

16. The apparatus of claim 6, further comprising a media access controller (MAC) coupled to said transmitter and said receiver.

17. The apparatus of claim 16, wherein said MAC comprises a means for controlling accessing to a WLAN medium.

18. The apparatus of claim 17, wherein said means for controlling includes carrier sense multiple access with collision avoidance (CSMA/CA).

19. The apparatus of claim 6, further comprising a demodulator/modulator facilitation module coupled to said transmitter and receiver.

20. The apparatus of claim 19, wherein said demodulator/modulator facilitation module comprises a means for modulating said baseband signal using differential binary phase shift keying (DBPSK).

21. The apparatus of claim 19, wherein said demodulator/modulator facilitation module comprises a means for de-modulating said down-converted signal using differential binary phase shift keying (DBPSK).

22. The apparatus of claim 19, wherein said demodulator/modulator facilitation module comprises a means for spreading said baseband signal.

23. The apparatus of claim 22, wherein said means for spreading comprises a means for spreading said baseband signal using a Barker code.

24. The apparatus of claim 19, wherein said demodulator/modulator facilitation module comprises a means for de-spreading said down-converted signal.

25. The apparatus of claim 24, wherein said means for de-spreading comprises a means for de-spreading said down-converted signal using a Barker code.

26. The apparatus of claim 19, wherein said demodulator/modulator facilitation module comprises a means for modulating said baseband signal using Gaussian phase shift keying (GPSK).

27. The apparatus of claim 19, wherein said demodulator/modulator facilitation module comprises a means for de-modulating said down converted signal using Gaussian phase shift keying (GPSK).

28. The apparatus of claim 19, wherein said demodulator/modulator facilitation module comprises a means for modulating said baseband signal using Orthogonal Frequency Division Multiplexing (OFDM).

29. The apparatus of claim 19, wherein said demodulator/modulator facilitation module comprises a means for de-modulating said down converted signal using Orthogonal Frequency Division Multiplexing (OFDM).

30. The apparatus of claim 19, wherein said demodulator/modulator facilitation module comprises a means for modulating said baseband signal using Complimentary Code Keying (CCK).

31. The apparatus of claim 19, wherein said demodulator/modulator facilitation module comprises a means for de-modulating said down converted signal using Complimentary Code Keying (CCK).

32. In a wireless LAN device, a method of down-converting a received RF signal, comprising:

down-converting said received RF signal according to a first control signal and a second control signal, resulting in a down-converted signal, wherein said second control signal is delayed relative to said first control signal by (0.5+n) cycles of said received RF signal, wherein n is an integer greater than or equal to 1;

de-spreading said down-converted signal using a spreading code, resulting in a de-spread signal; and

de-modulating said de-spread signal, resulting in a de-modulated signal.