Multimode receiver

• US 7,266,361 B2
• Filed: 10/17/2003
• Issued: 09/04/2007
• Est. Priority Date: 10/17/2002
• Status: Expired due to Fees

• Current Assignee: Toumaz Technology Ltd.
• Original Assignee: Toumaz Technology Ltd.
• Inventors: Burdett, Alison
• Primary Examiner(s): Orgad; Edan
• Assistant Examiner(s): HU, RUI MENG
• Application Number:
  US10/531,446
• Publication Number:
  US 20060126702A1
• Time in Patent Office: 1,418 Days
• Field of Search: 455/130, 455/313, 455/323, 455/341, 455/334, 455/335, 455/324, 375/136, 375/336
• US Class Current: 455/334
• CPC Class Codes: H03H 11/0444 Simulation of ladder networks
• CPC Class Codes: H03H 2011/0494 Complex filters
• CPC Class Codes: H04B 1/26 for superheterodyne receivers multiple frequency-changing H03D7/16
• CPC Class Codes: H04B 1/30 for homodyne or synchrodyne receivers demodulator circuits H03D1/22

Abstract

An electric circuit suitable for use as a radio receiver or part of a radio receiver, the electric circuit comprising amplification means, frequency mixer means, and filter means, wherein the frequency mixer mans is configurable to down-convert a wanted component of the amplified input signal to one of at least two intermediate frequency bands, and the filter means is dynamically reconfigurable between a first filter configuration which provides a first operating mode, and a second filter configuration which provides a second operating mode.

Claims

1. An electric circuit for use as a radio receiver or as part of a radio receiver, the electric circuit comprising:

amplification means for receiving an analogue input signal;

analogue frequency mixer means for receiving an output of the amplification means, the mixer means comprising a plurality of mixers being switchable into and out of use in order to configure the mixer means to down-convert a wanted component of the amplified input signal to one of at least two intermediate frequency bands, at least one of the mixers being reused for different configurations of the frequency mixer means;

analogue filter means for receiving an output of the frequency mixer means, the filter means being switchable between at least two filter configurations; and

control means coupled to the frequency mixer means and to the filter means and capable of selecting a frequency mixer means operating mode and filter configuration appropriate to the input signal to provide at least two of a low-IF, zero-IF, and superheterodyne architecture.

2. An electric circuit according to claim 1, the frequency mixer comprising four mixers configurable to provide at least two of:

a quadrature mixer for zero-IF use; and

a fully complex mixer for low-IF use; and

a single real mixer for superheterodyne use.

3. An electric circuit according to claim 1, wherein the filter means comprises a set of interconnected circuit elements, and switches which modify the interconnections between the circuit elements.

4. An electric circuit according to claim 1, wherein the filter means comprises a set of interconnected circuit elements, and means for providing adjustable bias signals or connections internal to the circuit elements, so as to substantially change their operating point or transfer function of the filter means.

5. An electric circuit according to claim 1, wherein one of said filter configurations is a low pass configuration for zero-IF use.

6. An electric circuit according to claim 1, wherein one of said filter configurations is a complex bandpass configuration for low-IF use.

7. An electric circuit according to claim 1, wherein one of said filter configurations is a real bandpass configuration for superheterodyne use.

8. An electric circuit according to claim 1, wherein the filter means provides quadrature inputs and quadrature outputs, the filter means being switchable to allow feedback to be passed from the quadrature outputs to opposite quadrature inputs.

9. An electric circuit according to claim 1, wherein the filter means comprises amplifiers and integrators arranged to simulate a passive filter, the time constants of the integrators being adjustable to adjust the filter means'"'"' transfer function.

10. An electric circuit according to claim 9, wherein the integrator is a transconductor capacitor structure having a tuneable bias current.

11. An electric circuit according to claim 1, wherein the filter means comprises transconductors and capacitors arranged to form active gyrators.

12. An electric circuit according to claim 11, wherein the transconductors are provided with tuneable bias currents, and the capacitors are provided with switches which may be used to switch the capacitors into or out of the filter active gyrators.

13. An electric circuit according to claim 1, wherein the filter means implements an all-pole lowpass filter.

14. An electric circuit according to claim 13, wherein the filter means is dynamically reconfigurable between the all-pole lowpass filter implementation and the elliptic filter implementation.

15. An electric circuit according to claim 1, wherein the filter means implements an elliptic filter.

16. An electric circuit according to claim 15, wherein the filter means is dynamically reconfigurable between the all-pole lowpass filter implementation and the elliptic filter implementation.

17. An electric circuit according to claim 1, wherein the filter means comprises a finite input response filter with adjustable delay sections and weights.

18. An electric circuit according to claim 1 and comprising detection means coupled to receive at an input the output of the filter means for extracting modulation information therefrom, the detection means being coupled to the control means so that the control means can switch the detection means between at least two operating modes.

19. An electric circuit according to claim 18, wherein the detection means can be switched between at least a real value and a complex modulus operating mode.

20. An electric circuit according to claim 1, wherein said filter means comprises a plurality of filters which can be switched into and out of use, at least one of the filters being reused in different filter configurations.