Abstract: In a direction finding system, pluralities of signals provided by different sets of less than all of a plurality of arrayed antennas are code division multiplexed, downconverted by a single receiver, A/D converted and separated to derive signals that are processed to estimate the directions of arrival of the signals received by the different sets of antennas at different frequencies. The signals from different antennas are coded with different codes that have a common M-sequence and different phases for the different antennas. The derived signals are processed to detect the presence of signals and simultaneously demodulate and estimate the directions of arrival of signals by the antennas at the different frequencies. The different sets of antennas from which the received signals are provided for coding and multiplexing are selectively varied in accordance with the estimated directions of arrival and estimated magnitudes.

Abstract: An high speed apparatus and method for extending a dynamic range of a signal processing device which receives an analog input signal. A peak indicator uses a 90.degree. phase shifter and zero crossing detector to indicate when the analog input signal is at a peak amplitude within each of its cycles, and an analog to digital converter (ADC) samples input signal amplitude when each peak amplitude is indicated to provide a digital control word for each sampled peak. A gain controller adjusts the gain of the analog input signal provided to the signal processing device in response to the digital word. Preferably the ADC calculates log.sub.2 of the sampled peak amplitude so that the digital word is a power-of-two operator, the gain controller compresses the analog input signal by a factor of one over the power-of-two, and the output signal from the signal processing device is thereafter expanded by a data shifter which shifts the output by an amount corresponding to the power-of-two.

Abstract: A system and method for adjusting the dynamic range of a receiver in a communication system in which an input signal is attenuated by a calculated amount before the input signal is provided to a mixer in the receiver. The attenuation amount is set so that reciprocal mixing noise caused by mixing the input signal with the local oscillator phase noise in the mixer is reduced until the total noise is the receiver noise floor (the sum of thermal noise and receiver noise figure), without degrading the signal-to-noise ratio of the input signal.