US 2014/0306720 A1 · Using a Shared Local Oscillator to Make Low-noise Vector Measurements

Abstract

Measurements, e.g. S-parameter measurements may be performed by obtaining a complex ratio of at least two signals, using a single signal-receiver while eliminating noise problems traditionally associated with single receiver systems. A Vector Signal Generator (VSG) may be used to generate the input stimulus (signal), making it possible to share the local oscillator (LO) signal of the VSG with a single vector receiver, such that the phase noise of the LO signal is common to both the VSG and the vector receiver. When the stimulus signal from the VSG is observed with the vector receiver, the LO phase noise is unobservable, resulting in a significant reduction of the phase noise in the measured signals in both the numerator and the denominator, which in turn leads to a significant reduction in the phase noise of the ratio while retaining the benefits of a simple, single receiver.

Claims21

Dependent claims

A measurement system comprising:

a local oscillator configured to generate a periodic signal;
a signal generator configured to receive the periodic signal, and generate a stimulus signal based on the received periodic signal;
a test port configured to output a test signal based on the stimulus signal;
and
a receiver configured to:
receive the periodic signal;
alternately receive, as an input signal, a first coupled signal derived from the stimulus signal, and a second coupled signal derived from the stimulus signal;
generate an output signal based on the received input signal according to the periodic signal.

5 more elements

Dependencies are inferred from the claim text.

Using a Shared Local Oscillator to Make Low-noise Vector Measurements

Life of this patent

Using a Shared Local Oscillator to Make Low-noise Vector Measurements

Life of this patent

Abstract

Claims21