Abstract: A system and method for testing wireless communication devices uses a waveguide designed for operation beyond cutoff for frequencies used by the wireless communication device to be tested. The waveguide has first and second ends with at least an opened first end to permit the easy insertion and removal of the wireless communication device. An antenna located within the waveguide and coupled to an external test system permits wireless communication between the external test system and the wireless communication device when inserted in the waveguide. Radio frequency (RF) signals propagate between the antenna located within the waveguide and the wireless communication device when inserted into the waveguide. The length of the waveguide is designed to provide sufficient attenuation of RF transmissions when measured at the opened end of the waveguide.

Abstract: A compact selectable AC/DC coaxial coupling having a cylindrical signal coupling capacitor disposed within a section of coaxial transmission line. Inner and outer plates of the capacitor are electrically connected to an external connector and the center conductor of the transmission line, respectively. A radially biased conductive collet or a conductive mesh axially disposed on the center conductor is biased into and out of contact with the inner plate of the capacitor to enable or disable DC coupling. Alternatively, a resilient contact member is displaced through an externally accessible actuating rod to connect the center conductor to the inner plate of the capacitor. The integral nature of these switching mechanisms within a coaxial environment provides both low insertion losses and continuous impedance matching.

Abstract: Method and apparatus for improving the signal-to-noise ratio of a divide-by-N phase-locked loop includes a variable divider circuit to provide a plurality of feedback signals of substantially equal phase. Each of the plurality of feedback signals includes a signal component and a noise component wherein the signal components of the plurality of feedback signals have substantially equal phase and wherein the noise components of the plurality of feedback signals are not substantially correlated. A respective plurality of control circuits is provided to combine the plurality of feedback signals with a reference signal to provide a plurality of control signals wherein each control signal is a substantially direct current voltage the magnitude of which is proportional to the phase difference between the reference signal and the feedback signal which comprised its origin.