System and method for measuring radio frequency phase shift of an inline device
AssigneeGM Global Technology Operations LLC
InventorIgal Kotzer
Life of this patent
Estimating the term…
Abstract
A testing device includes an oscillator circuit with an inline device. The oscillator circuit includes a loop having a variable gain amplifier and a variable feedback block. The inline device is installed between the variable gain amplifier and the variable feedback block. An output of the variable feedback block is input to the variable gain amplifier. A processor varies a phase of the variable feedback block to locate a block phase shift of the variable feedback block at which the oscillator circuit generates an output signal, determines a device phase shift of the inline device from the block phase shift, and adjusts an operation of a driven circuit operating off of the output of the oscillator circuit using the device phase shift of the inline device.
Claims20
A method for determining a phase shift of an inline device, comprising:
- determining a first block phase shift of an oscillator circuit that allows the oscillator circuit to satisfy a Barkhausen phase condition, the oscillator circuit including a loop having a variable gain amplifier, an adjustable phase shifter and a feedback network, wherein an output of the variable gain amplifier is input to the adjustable phase shifter and the output of the feedback network is input to the variable gain amplifier;
- inserting a transmission line into the loop between the output of the variable gain amplifier and the input to the adjustable phase shifter;
- varying a phase of the oscillator circuit to locate a second block phase shift of the oscillator circuit at which the oscillator circuit generates an output signal;
- determining a device phase shift of the transmission line from a difference of the first block phase shift and the second block phase shift;
- and
- adjusting an operation of a driven device operating off of the output of the oscillator circuit using the device phase shift of the transmission line.
An oscillator circuit, comprising:
- a loop comprising a variable gain amplifier, a feedback network and an adjustable phase shifter, wherein an output of the variable gain amplifier is input to the adjustable phase shifter and the output of the feedback network is input to the variable gain amplifier, wherein a transmission line is insertable into the loop between the output of the variable gain amplifier and the input to the adjustable phase shifter;
- a processor configured to:
- determine a first block phase shift of the oscillator circuit that allows the oscillator circuit to satisfy a Barkhausen phase condition without the transmission line;
- vary a phase of the oscillator circuit to locate a second block phase shift of the oscillator circuit at which the oscillator circuit generates an output signal with the transmission line inserted;
- determine a device phase shift of the transmission line from a difference of the first block phase shift and the second block phase shift;
- and
- adjust an operation of a driven circuit operating off of the output of the oscillator circuit using the device phase shift of the transmission line.
A testing device, comprising:
- an oscillator circuit comprising:
- a loop comprising a variable gain amplifier, a feedback network and an adjustable phase shifter, wherein an output of the variable gain amplifier is input to the adjustable phase shifter and the output of the feedback network is input to the variable gain amplifier, wherein a transmission line is insertable into the loop between the output of the variable gain amplifier and the input to the adjustable phase shifter;
- and
- a processor configured to:
- determine a first block phase shift of the oscillator circuit that allows the oscillator circuit to satisfy a Barkhausen phase condition without the transmission line;
- vary a phase of the oscillator circuit to locate a second block phase shift of the oscillator circuit at which the oscillator circuit generates an output signal with the transmission line inserted;
- determine a device phase shift of the transmission line from a difference of the first block phase shift and the second block phase shift;
- and
- adjust an operation of a driven circuit operating off of the output of the oscillator circuit using the device phase shift of the transmission line.
Dependencies are inferred from the claim text.