Square wave testing of two-point polar amplifiers

• US 8,200,171 B1
• Filed: 05/23/2008
• Issued: 06/12/2012
• Est. Priority Date: 05/30/2007
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm Atheros Incorporated (Qualcomm, Inc.)
• Inventors: Husted, Paul J.
• Primary Examiner(s): Nguyen, Duc M
• Application Number:
  US12/126,848
• Time in Patent Office: 1,481 Days
• Field of Search: 455/67.11, 455/67.14, 455/115.1, 455/115.2, 455/102, 455/108, 455/110, 455/114.3
• US Class Current: 455/115.1
• CPC Class Codes: H03C 1/62 Modulators in which amplitude of carrier component in output is dependent upon strength of modulating signal, e.g. no carrier output when no modulating signal is present H03C1/28 - H03C1/34, H03C1/46, H03C1/48 take precedence
• CPC Class Codes: H03C 5/00 Amplitude modulation and angle modulation produced simultaneously or at will by the same modulating signal H03C7/00 takes precedence

Abstract

A method and apparatus for testing a polar transmitter uses at least one square wave waveform as test stimuli replacing a multitone waveform. Each square wave signal is coupled one at a time to a frequency modulating input of the polar transmitter. The output of the polar transmitter is analyzed by observing the amplitude and frequency of the demodulated components corresponding to each square wave signal.

Claims

1. A method of testing a polar transmitter, the method comprising:

providing at least one square wave waveform as test stimuli;

coupling each square wave signal to a frequency modulating input of the polar transmitter; and

analyzing an output of the polar transmitter by observing an amplitude and a frequency of demodulated components corresponding to each square wave signal, wherein a fundamental frequency of each square wave signal is approximately equal to one frequency of a predetermined multitone signal.

2. A transmitter system comprising:

a polar transmitter;

a square wave generator configured to generate square wave signals, wherein a fundamental frequency of each square wave signal is approximately equal to one frequency of a predetermined multitone signal; and

a multiplexer for selectively providing one of an output of the square wave generator and modulating frequency data to the polar transmitter.

3. The transmitter system of claim 2, further including a central processing unit for, during a test mode, configuring the square wave generator to generate each square wave signal from a family of square waves and configuring the multiplexer to couple the output of the square wave generator to the polar transmitter.