Method for removing phase instabilities caused by flexure of cables in microwave network analyzer measurements

A method of removing phase errors in any signal caused by movement of a cable carrying the signal comprising:

• terminating said cable with a reflection means having a stable phase;
• providing a source of microwave frequency electromagnetic energy signals;
• transmitting a microwave frequency electromagnetic energy signal from said source along said cable from an input to an output thereof;
• sampling said transmitted signal;
• reflecting a portion of said transmitted signal from the reflection means terminating said cable;
• sampling said reflected signal;
• measuring the phase difference between said transmitted and reflected signals to establish a predetermined reference signal representative of said phase difference;
• removing said reflection means from termination of said cable;
• connecting a device under test (DUT) to said cable;
• applying said transmitted microwave freqeuncy signal to said DUT;
• sampling said transmitted signal and any signal reflected by said DUT;
• measuring the phase difference between said transmitted and DUT reflected signals to establish an error signal;
• comparing said error signal to said predetermined reference signal to develop a correction signal;
• and
• applying said correction signal to said source of microwave frequency signals for changing the characteristics of said transmitted signal to compensate for said error.