US 7,065,466 B2 · Attenuator test system

Abstract

System for testing attenuators by a flatness and standing wave ratio tests which includes a vector network analyzer (VNA) adapted to be coupled to a device under test (DUT) and which provides an input stimulus signal for the DUT and, when certain conditions are satisfied, receives an output signal from the DUT, and a calibration receiver adapted to be coupled to the DUT via a down-converter. When certain conditions are satisfied, the output signal from the DUT is sent to the calibration receiver (through the down-converter to be possibly modified thereby depending on the testing frequency). A signal generator provides a local oscillator (LO) signal for the down-converter. A control unit is connected to the instruments and embodies software which analyzes the testing conditions, i.e., the attenuator value being tested, and selects whether the network analyzer or the calibration receiver will measure the output signal from the DUT.

Claims19

Dependent claims

A system for testing attenuators, comprising:

a vector network analyzer adapted to be coupled to a device under test (DUT), said network analyzer being arranged to provide an input stimulus signal for the DUT and being arranged to receive an output signal from the DUT;
a down-converter having frequency conversion capability;
a signal generator for providing a local oscillator (LO) signal for said down-converter;
a calibration receiver adapted to be coupled to the DUT via said down-converter such that an output signal from the DUT is receivable by said down-converter, optionally modified thereby and sent to said calibration receiver;
and
a control unit coupled to said network analyzer and said calibration receiver and arranged to select which of said network analyzer and said calibration receiver measure the output signal from the DUT.

3 more elements

A method for measuring flatness of an attenuator over a specified frequency range, comprising:

forming a file of attenuator values to be used in the test;
determining instruments to be used in the measurement based upon predetermined conditions relating to the attenuator values in the file, the instruments being selected from a vector network analyzer, a calibration receiver and a down-converter whereby when the attenuator values in the file are all less than or equal to 50 dB, only the network analyzer is used, when the attenuator values in the file are all above 50 dB, only the calibration receiver and the down-converter are used and when at least one of the attenuator values in the file is above 50 dB and at least one of the attenuator values in the file is less than or equal to 50 dB, the network analyzer, the calibration receiver and the down-converter are used;
and
sequentially testing each of the attenuator values by
when the attenuator value being tested is less than or equal to 50 dB, connecting a device under test (DUT) to the network analyzer, directing an input stimulus signal from the network analyzer to the DUT and receiving and measuring output signals from the DUT at the network analyzer,
when the attenuator value being tested are is greater than 50 dB, measuring the source power at each frequency, while down-converting the frequency when greater than 1 GHz, without the DUT being connected in a test setup with the calibration receiver and down-converter, and when the source power measurements are completed for the frequencies in the specified frequency range, connecting the DUT to the test setup and measuring the source power at each frequency value, while down-converting the frequency when greater than 1 GHz.

3 more elements

Dependencies are inferred from the claim text.

Attenuator test system

Life of this patent

Attenuator test system

Life of this patent

Abstract

Claims19