Method and apparatus for improving dynamic range in a communication system

• US 7,321,751 B2
• Filed: 11/27/2002
• Issued: 01/22/2008
• Est. Priority Date: 04/16/1999
• Status: Expired due to Fees

• Current Assignee: ParkerVision, Inc.
• Original Assignee: ParkerVision, Inc.
• Inventors: Moses, Charley D Jr., Looke, Richard C, Bultman, Michael J, Rawlins, Michael W, Rawlins, Gregory S, Sorrells, David F, Cook, Robert W
• Primary Examiner(s): Urban; Edward F.
• Assistant Examiner(s): CHOW, CHARLES CHIANG
• Application Number:
  US10/305,299
• Publication Number:
  US 20030181190A1
• Time in Patent Office: 1,882 Days
• Field of Search: 455/296, 455/118, 455/424, 455/425, 455/456.5, 455/456.6, 455/561, 455/550.1, 455/575.1, 455/189.1, 455/190.1, 455/313, 455314-318, 455/319, 455/323, 455/302, 455/324, 455/325, 455/326, 455/333, 455/310, 455/295, 455/311, 327/113, 327/116, 327/355, 327/356, 327357-363, 327/124, 327/307, 327/561, 327/563, 327/427, 327/407, 327/408, 327434-437, 330/307, 330/296
• US Class Current: 455/118
• 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: H04B 1/12 Neutralising, balancing, or compensation arrangements
• CPC Class Codes: H04B 1/123 using adaptive balancing or compensation means adaptive filter circuits and algorithms H03H
• CPC Class Codes: H04B 1/28 the receiver comprising at least one semiconductor device having three or more electrodes
• CPC Class Codes: H04B 1/30 for homodyne or synchrodyne receivers demodulator circuits H03D1/22

Abstract

An apparatus for improving dynamic range includes a frequency down-conversion module that receives an input signal and a bias circuit. The bias circuit includes a first resistor and a second resistor. The first resister has a first terminal coupled to a bias point and a second terminal coupled to a first voltage reference. The second resistor has a first terminal coupled to the bias point and a second terminal coupled to a second voltage reference. The bias point is coupled to the input signal. The frequency down-conversion module outputs a down-converted output signal. The bias circuit thereby adjusts a voltage of the input signal.

Claims

1. An apparatus for improving dynamic range, comprising:

a frequency down-conversion module that receives an input signal; and

a bias circuit comprising;

a first resistor with a first terminal coupled to a bias point and a second terminal coupled to a first voltage reference; and

a second resistor with a first terminal coupled to said bias point and a second terminal coupled to a second voltage reference;

wherein said bias point is coupled to said input signal;

wherein said frequency down-conversion module comprises a switch and a storage element;

wherein the switch transfers energy from the input signal to the storage element by non-impulse under-sampling the input signal according to non-impulse pulses of a control signal;

wherein an output signal is generated by integrating the transferred energy;

wherein the bias point is configured to bias the input signal to have a center voltage that varies within a minimum and a maximum of a voltage range of the control signal; and

wherein said frequency down-conversion module outputs a down-converted output signal.

2. The apparatus of claim 1, further comprising a tank circuit, wherein said bias point is coupled to said input signal via said tank circuit.

3. The apparatus of claim 2, wherein said tank circuit comprises a capacitor and an inductor connected in parallel and coupled between said input signal and said bias point.

4. The apparatus of claim 1, wherein said bias circuit further comprises a capacitor, wherein a first terminal of said capacitor is coupled to said bias point, and a second terminal of said capacitor is coupled to a third voltage reference.

5. The apparatus of claim 4, wherein said capacitor stabilizes said bias point.

6. The apparatus of claim 1, wherein a first node of said storage element is coupled to a node of said switch, and a second node of said storage element is coupled to a reference potential.

7. The apparatus of claim 6, wherein said storage element comprises a capacitor.

8. The apparatus of claim 1, further comprising an impedance match in series with said input signal.

9. The apparatus of claim 8, wherein said impedance match comprises an inductor.

10. The apparatus of claim 1, further comprising a control signal generator that outputs said control signal.

11. A method of down-converting an electromagnetic signal and improving dynamic range, comprising:

(1) applying a bias voltage to an input signal; and

(2) frequency down-converting the input signal with a frequency down-conversion module to a down-converted signal;

wherein step (2) comprises using a switch to transfer energy from the biased input signal to a storage component by non-impulse under-sampling the input signal according to non-impulse pulses of a control signal;

wherein step (2) comprises generating an output signal by integrating the transferred energy; and

wherein step (1) comprises producing the biased input signal to have a center voltage that varies within a minimum and a maximum of a voltage range of the control signal.

12. The method of claim 11, wherein step (1) comprises the step of:

adjusting the center voltage of the input signal.

13. The method of claim 11, wherein step (1) comprises the step of:

(A) coupling the input signal to a center terminal of a resistor divider circuit.

14. A method of down-converting an electromagnetic signal and improving dynamic range, comprising:

(1) applying a bias voltage to an input signal; and

(2) frequency down-converting the input signal with a frequency down-conversion module to a down-converted signal by non-impulse under-sampling the input signal according to non-impulse pulses of a control signal to thereby transfer energy from the input signal, and integrating the transferred energy;

wherein step (1) comprises;

(A) coupling the input signal to a center terminal of a resistor divider circuit, wherein step (A) comprises;

(i) using a tank circuit to couple the input signal to the center terminal of the resistor divider circuit.

15. A method of down-converting an input signal, comprising the steps of:

(1) receiving an input signal;

(2) biasing the input signal with a bias voltage to produce a biased input signal; and

(3) down-converting the biased input signal to a down-converted signal using a frequency down-conversion module;

wherein step (3) comprises transferring energy from the biased input signal by non-impulse under-sampling the input signal according to non-impulse pulses of a control signal;

wherein step (3) further comprises integrating the transferred energy thereby generating the down-converted signal; and

wherein step (2) comprises producing the biased input signal to have a center voltage that varies within a minimum and a maximum of a voltage range of the control signal.

16. The method of claim 15, wherein step (1) further comprises receiving a radio frequency (RF) signal.

17. The method of claim 15, wherein step (1) further comprises receiving the input signal through an impedance match.

18. The method of claim 17, wherein step (1) further comprises receiving the input signal through an inductor.

19. The method of claim 15, wherein step (2) further comprises generating the bias voltage using a voltage divider circuit.

20. The method of claim 19, wherein step (2) further comprises receiving the bias voltage from the voltage divider circuit.

21. The method of claim 20, wherein step (2) further comprises receiving the bias voltage from the voltage divider circuit via a tank circuit.

22. The method of claim 15, wherein step (2) further comprises ensuring the center voltage is maintained substantially equal to a midpoint of the voltage range.