A dual-mode telephone with a satellite communication adapter is disclosed. According to one embodiment of the present invention, a cellular-type handportable phone is equipped with a connector for the attachment of accessories. This connector provides a satellite communications adapter accessory access to the handset's signal processing resources which may operate in an alternative mode to process signals received from a satellite and converted by the adapter into a suitable form for processing. The processing translates the satellite signals into voice or data, and vice-versa.

Satellite communications adapter for cellular handset

These range errors can be corrected by accurately estimating the frequency deviation error of a radar system. The present invention improves target position determination performance in a radar system by reducing errors introduced by the frequency deviation error. In accordance with a first range calibration technique of the present invention, the radar system measures the range, Doppler range rate, and azimuth angle of a target during at least two successive time instances. The method corrects the range using a frequency deviation correction factor, K. A second calibration technique of the present invention is based on giving more weight to tracks with more reliable data. The frequency deviation correction factor is updated and used for correcting the range.

Method and apparatus for range correction in a radar system

A method of processing radar returns derived from a new radar waveform. The method processes radar returns derived from transmitting the radar waveform to provide simultaneous matched processing and range profiling of different size objects in the presence of clutter. In the present method, radar returns are digitized and processed to produce pulse compressed radar returns having a predetermined (169:1) pulse compression ratio. A pulse to pulse fast Fourier transform on each RF step is performed on the pulse compressed radar returns. The Fourier transformed radar returns are then simultaneously processed by three processing channels, one each for ships, boats and submarines to provide detection of the different size objects. The waveform permits concurrent detection, discrimination, and high resolution range imaging of detected objects within a single dwell, using a single waveform. Thus, a radar search mode using the waveform integrates several search functions without increasing search frame time.

Processing method using an advanced radar waveform for simultaneous matched processing and range profiling of different size targets

A digital compensator for radar transmitter instabilities for use in a digital MTI system. The I and Q coherent phase detector outputs are continuously monitored for phase, amplitude and timing instabilities and arithmetic correction signals are generated and applied to the digitized received signal values to compensate for these instabilities which are particularly characteristic of pulsed magnetron transmitters, for example.

Digital compensator for transmitter instability

A pulse-compression, MTI, doppler-radar system for determining target velty information from a single, frequency-coded uncompressed target-return pulse includes a coded modulator, two pulse compressors, and a phase-comparison processor. The coded modulator generates for transmission an uncompressed pulse with the first and second halves of the pulse coded with the even and odd harmonic sidebands of a pulse repetition frequency, respectively. The first and second halves of the pulse returning from the target are pulse compressed simultaneously by the two pulse compressors. The phase comparison processor then determines the phase difference between the compressed pulses to obtain the target velocity information.

Frequency-coded monopulse MTI

A coherent digital multifunction processor that is capable of multiple-mode processing and can also perform rapid inter-mode switching. Additionally, while processing data in a given mode, the subject processor is capable of self-synchronization, thereby obviating the requirement for external synchronous devices. The instant processor has a central control which may suitably utilize a general purpose computer in one embodiment. The primary modes of operation of the subject processor are: a pulse doppler acquisition and/or tracking mode, a moving target indicator mode, and an incoherence mode.

A Diamant

Papers

Coherent digital multifunction processor