System and method for signal limiting

• US 8,014,724 B2
• Filed: 10/01/2004
• Issued: 09/06/2011
• Est. Priority Date: 10/21/1999
• Status: Expired due to Fees

• Current Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Moloudi, Shervin
• Primary Examiner(s): Milord; Marceau
• Application Number:
  US10/957,043
• Publication Number:
  US 20050054295A1
• Time in Patent Office: 2,531 Days
• Field of Search: 455/63.1, 455/20, 455/228, 455/296, 455/118, 455/306, 455/255, 455/258, 455/307, 455/323, 375/285, 375/346, 375/148, 375/133, 375/322, 331/16, 331/11
• US Class Current: 455/63.1
• CPC Class Codes: H03B 21/01 by beating unmodulated signals of different frequencies
• CPC Class Codes: H03C 3/0983 containing in the loop a mixer other than for phase detection
• CPC Class Codes: H03H 11/1291 Current or voltage controlled filters
• CPC Class Codes: H03H 2011/0494 Complex filters
• CPC Class Codes: H03H 21/0001 Analogue adaptive filters
• CPC Class Codes: H03H 21/0012 Digital adaptive filters
• CPC Class Codes: H03J 2200/10 Tuning of a resonator by means of digitally controlled capacitor bank
• CPC Class Codes: H03L 2207/06 Phase locked loops with a controlled oscillator having at least two frequency control terminals
• CPC Class Codes: H03L 7/0891 the up-down pulses controlling source and sink current generators, e.g. a charge pump
• CPC Class Codes: H03L 7/099 concerning mainly the controlled oscillator of the loop
• CPC Class Codes: H03L 7/104 using an additional signal from outside the loop for setting or controlling a parameter in the loop H03L7/107, H03L7/12 take precedence
• CPC Class Codes: H04B 1/40 Circuits
• CPC Class Codes: H04B 17/104 of other parameters, e.g. DC offset, delay or propagation times
• CPC Class Codes: H04B 17/14 of the whole transmission and reception path, e.g. self-test loop-back
• CPC Class Codes: H04B 17/19 Self-testing arrangements

Abstract

Methods and systems for processing a signal with a corresponding noise profile are disclosed. Aspects of the method may comprise analyzing spectral content of the noise profile. At least one noise harmonic within the signal may be filtered based on said analyzed spectral content. The filtered signal may be limited. The noise profile may comprise a phase noise profile. The signal may comprise at least one of a sinusoidal signal and a noise signal. At least one filter coefficient that is used to filter said at least one noise harmonic may be determined. The filtering may comprise low pass filtering and the limiting may comprise hard-limiting the filtered signal. The signal may be modulated prior to the filtering. The signal may be downconverted prior to the modulating. At least one signal component of the signal may be downconverted.

Claims

1. A system for processing a signal with a corresponding noise profile, the system comprising:

a processor that analyzes spectral content of the corresponding noise profile;

a modulator that modulates the signal;

a filter that filters at least one noise harmonic within the signal based on said analyzed spectral content;

a limiter that limits said filtered signal;

a downconverter that downconverts the signal prior to said modulating, wherein said downconverter downconverts at least one signal component of the signal, and wherein said at least one signal component of the signal comprises one or both of an in-phase signal component and/or a quadrature signal component;

a modulation mixer that modulates said in-phase signal component and/or said quadrature signal component with a modulation frequency; and

an adder that adds said modulated in-phase signal component and said modulated quadrature signal component to obtain a downconverted modulated signal.

2. A system for processing a signal with a corresponding noise profile, the system comprising:

at least one processor that analyzes spectral content of the corresponding noise profile;

said at least one processor modulates the signal;

said at least one processor filters at least one noise harmonic within the signal based on said analyzed spectral content;

said at least one processor limits said filtered signal;

said at least one processor downconverts the signal prior to said modulating, wherein said downconverting comprises downconverting at least one signal component of the signal, and wherein said at least one signal component of the signal comprises one or both of an in-phase signal component and/or a quadrature signal component;

said at least one processor modulates said in-phase signal component and/or said quadrature signal component with a modulation frequency; and

said at least one processor adds said modulated in-phase signal component and said modulated quadrature signal component to obtain a downconverted modulated signal.