Abstract: Real-time calibration of a tunable matching network that matches the dynamic impedance of an antenna in a radio frequency transmitter system. The radio frequency transmitter system includes two non-linear equations that may be solved to determine the reflection coefficient of the antenna. The tunable matching network is repeatedly perturbed and the power reflected by the antenna is measured after each perturbation at the same node within the tunable matching network. The power values are used by an optimizer in converging to a solution that provides input impedance of the antenna. The elements of the matching circuit are adjusted to match the input impedance of the antenna.

Abstract: A fixed wireless terminal utilizes a method for accessing a wireless local loop (WLL) telephone network to provide both a diagnostic mode of operation and a digital data delivery mode of operation in a system which utilizes a protocol which provides support for only the digital data delivery mode of operation. The method includes setting up a call to a WLL device which includes a mobile station and a communication interface. The mobile station receives call setup signals followed optionally by a predetermined guard time. The communication interface is responsive to a predetermined guard time for switching to a diagnostic mode, and in the absence of the predetermined guard time being transmitted, the communication interface maintains the digital data delivery mode.