Abstract: Optimization of a cellular network is facilitated by an apparatus that performs drive test measurements of a cellular network to identify co-channel interference. The co-channel interference is identified by measuring the signal strengths at various locations within a cell sector and analyzing the recorded information. A key aspect of the invention is synthesizing the received signals to identify the cellular transmitters originating the signals. If signal energy is detected from more than one cellular transmitter on a single frequency, the co-channel interference is identified. This process is particular well suited within a GSM cellular system by detecting the transmission of forward control channel messages and using the information within the forward control channel messages to identify the origination cellular transmitters.

Abstract: A multi-voltage transformer includes an average current loop circuit, a pulse width generator, a push-pull driver, and a pulse width modulator coupled to the average current loop circuit, the pulse width generator, and the push-pull driver for generating pulses for driving a power supply. In a standard operating mode, the power supply is powered by an AC power source. The power supply uses the AC power source to drive the output of the power supply and to recharge the batteries associated with the power supply. When the power supply is operating on AC power, it translates the AC sinusoidal wave signal into a saw tooth wave signal that drives a pulse width modulator. When the AC power source is interrupted, the transformer switches the power source from the AC power source to a battery backup source. The transformer is designed to operate with a variety of battery voltages.

Abstract: Intermittent miscounts generated by counters used in a phase-locked loop (“PLL”) are precisely measured by detecting changes to a predetermined waveform, such as a sawtooth waveform. The miscounts are detected using an open loop, not closed loop, set-up which comprises two separate signal generators feeding two separate frequencies into MAIN and REF counters of a PLL. Offsetting the frequencies slightly and integrating an output generates the predetermined waveform. Thereafter, miscounts can be detected by comparing waveforms corresponding to miscounts to theoretically predicted, predetermined waveforms.