Abstract: The present invention provides a software defined radio transceiver that includes a programmable cellular radio front end and a programmable baseband processor. The programmable cellular radio front end is typically a digital radio frequency processor configured to support a cellular communication standard. The programmable baseband processor is connected to the digital radio frequency processor.

Abstract: The present invention provides a software defined radio transceiver that includes a programmable cellular radio front end and a programmable baseband processor. The programmable cellular radio front end is typically a digital radio frequency processor configured to support a cellular communication standard. The programmable baseband processor is connected to the digital radio frequency processor.

Abstract: A transceiver, method, and system for optical communication. The system including at least a first and second optical transceivers each having an optical assembly unit with a single-aperture for transmitting and receiving optical communication signals and receiving beacon signals, and the optical assembly unit having one or more light sources attached thereto for emitting beacon signals. The transceiver, method, and system providing for superior tracking of optical communication signals/light beams transmitting information in free-space.

Abstract: The present invention is a channel-aided, decision-directed delay-locked loop (CADD-DLL) implemented, in one embodiment of the present invention, for pilot-symbol-aided (PSA) code-division multiple-access (CDMA) communication. In one embodiment of the present invention initial pseudo-noise (PN) code acquisition is accomplished with the aid of a conventional non-coherent PN code acquisition system, and, upon acquiring the initial PN code epoch, PN code tracking is performed using a channel-aided, decision-directed PN code tracking mechanism. The tracking loop in accordance with the present invention includes delay and advance PN correlators. The correlators are followed by data and phase correction as well as amplitude matching devices, the outputs of which are subtracted to form an error signal for code tracking purposes.

Abstract: The present invention provides for joint estimation of data clock and frame timing in, for example, an M-ary phase-shift-keying (MPSK) signaling scheme with raised-cosine (RC) baseband pulse shaping. Asynchronous samples of the MPSK signal are obtained at a sampling rate greater than the Nyquist rate. A Fast Fourier Transform (FFT) processor processes the acquired samples, and the outcome is passed on to an absolute-value device followed by a peak detector. The present invention then operates to extract clock and frame information from the MPSK signal using a dotting pattern. In addition to clock recovery, the present invention provides for frame synchronization using the dotting pattern. The present invention thus eliminates the need for a long unique work (UW) frame synchronization pattern often included in the preamble of, for example, a time-division multiple-access (TDMA) signal to establish frame synchronization.

Abstract: An interferometric, self-homodyne optical receiver is disclosed for detecting and demodulating phase modulated optical signals without requiring a local oscillator normally associated with coherent optical receivers. The self-homodyne receiver includes an interferometer having a phase modulator optically coupled to one channel of the interferometer and a phase-locked arrangement providing electrical signals which control the phase modulator and phase of one channel of the interferometer with respect to the other channel.