Method and means for testing high frequency equipment

Claim 1

In a system for measuring the reflection coefficient of VSWR or a high frequency component device, a circuit comprising a sweep generator provided with an automatic gain control for providing a signal comprised of a sweep of signal frequencies over a high frequency predetermined range of frequencies, a transmission line, means for injecting said signal into one end of said tRansmission line, said transmission line being connected at its other end to the device under test, first detector means coupled to the line at one point thereof, second detector means coupled to the line at a single point spaced from the first detector toward the device being tested, and separated from said device by a plurality of wave lengths at the lowest frequency within the range, said transmission line between the sweep frequency generator and the device being free to transmit incident and all reflected energy, whereby the first and second detecting means sense both the incident and reflected energy on the line at their point of coupling thereto, means for applying the output of the first detecting means to the gain control of the sweep frequency generator to maintain the voltage on the line at the point of coupling of the first detecting means thereto at a substantially constant level, and means for measuring the output of the second detecting means to determine the reflection coefficient or VSWR of the device.