Abstract: The Highly Structured Rosette Antenna Array Data Communications System is a high capacity wireless network in which data is communicated from and to remotely located subscribers. The system uses cells that are comprised of a multiplicity of oblong microcells arranged in a circle, giving the cell a rosette-like pattern like frequency channels are assigned to every N′″ microcell, where N is the number of distinctly different frequency channels. The sum of the distinctly different channels is the total bandwidth assigned to the rosette. Typically, if M is equal to the total number of microcells in the rosette, then M/N is equal to the number of like-frequency microcells in the rosette.

Abstract: A simplified method of history handling for the Viterbi decoding of convolutional codes is described herein. The state number, or one or more of the most-significant bits of the state number, is loaded into the corresponding state history. Each state number represents the sequence of data bits that, in convolutional encoding, would give rise to the corresponding state. The most recent data bit provides the least significant bit of the state number. This invention reduces the processing requirements associated with the handling of the history, and is especially useful for decoder implementations using general-purpose processors.

Abstract: This invention provides a multistage frequency multiplier having a plurality of frequency doublers. Each doubler incorporates a three-terminal transistor device and is connected to an adjacent doubler via an interstage network. The network comprises a transmission line having its electrical parameters selected to achieve conjugate impedance matching at the intermediate harmonic frequency generated by the corresponding doubler. This network also includes a quarter-wavelength open-ended stub for suppressing a main input frequency component received by the corresponding frequency doubler. A shunt resistor on the transistor gate is preferably used to stabilize the network. This interstage network simplifies overall circuit topology to reduce total circuit size, and provides increased drive power levels to permit broader bandwidth and stabilize required output level from a local oscillator.

Abstract: Interleavers based on golden-section increments are disclosed for use with Turbo and Turbo-like error-correcting codes. The interleavers have a tendency to maximally spread the error-bursts generated by an error-burst channel or decoder, independent of the error-burst length. The code block size uniquely defines a golden section increment without having to perform a time consuming search for the best increment value. The disclosed embodiments include golden relative prime interleavers, golden vector interleavers and dithered golden vector interleavers. Also disclosed are methods to reduce the size of memory required for storing the interleaving indexes.

Abstract: A method for the joint detection of multiple coded digital signals that share the same transmission medium in a manner that causes mutual interference. The method is comprised of two steps that are applied to preliminary estimates of each digital signal, one or more times. The first step is to obtain reliability estimates for each data element of each digital signal by combining the preliminary estimates, a statistical model for the interference, and any a priori information regarding the data elements. The second step is to revise these reliability estimates for each digital signal based on the forward error correction code used for that digital signal. When the steps are repeated, the revised reliability estimates from the second step are used as a priori information for the first step.

Abstract: The invention comprises an enhancement to max-log-APP processing that significantly reduces performance degradation associated with introducing the "max" approximation into log-APP computations, while still maintaining lower computational complexity associated with max-log-APP processing. This enhancement is achieved by adjusting extrinsic information produced by a max-log-APP process where the magnitude of the extrinsic information is reduced, for example, by multiplying it with a scale factor between 0 and 1.

Abstract: A method of encoding data is described herein. According to the method, source data elements are coded using one or more product codes having a common component code. The resulting one or more primary product codewords consist of a plurality of first codewords of the common component code. One or more first sets of codewords of the common component code are assembled such that each of the first sets comprises two or more distinct first codewords forming part of a same primary product codeword. Each of the codewords of each of the first sets is codeword-mapped to a second codeword of the common component code using a one-to-one codeword-mapping. One or more second sets of second codewords are provided, where each second set corresponds to a first set of codewords. The codeword-mapping includes re-ordering, according to a known interleaving pattern, the symbols within a codeword.

Abstract: An antenna array is disclosed wherein radiators are parasitically coupled to each other, forming an efficient feed network. Parasitic coupling of patches is arranged so that some patches are fed by a plurality of other patches which are parasitically coupled thereto. The resulting array is low profile and high gain. By positioning patches on different layers with different dimensions, a broadband design for the antenna array is achieved.

Abstract: Due to the frequency dependence of phasing mechanisms applied in planar printed reflectors, when using planar printed reflector antennas beam squint occurs as the frequency is scanned within the operating band. In order to reduce or eliminate beam squint, an incident signal incident upon a reflector is altered in such a way that the outgoing signal retains a same direction. In an embodiment, this is achieved by providing feed elements in different locations, each feed element for feeding a signal of a different frequency. In another embodiment, two reflector arrays are used wherein beam squint caused by the first reflector array is compensated for by the second reflector array.

Abstract: A dielectric resonator antenna system is disclosed wherein a dielectric material having a high dielectric constant is placed between a dielectric resonator antenna (DRA) and the antenna feed. Preferably the dielectric material having a high dielectric constant is either in the form of an insert within a cavity of the DRA or alternatively is in the form of a thin layer between the feed and the DRA for enhancing coupling therebetween. It is preferred that the high dielectric constant material be at least twice the value of the dielectric resonator antenna.

Abstract: In the past, parabolic offset reflector antennas were fed a signal through a corrugated horn in order to optimize field distribution and polarization at the reflector. It has been found that cost savings and other advantages are realized by using an array of radiating patches. The geometrical placement of the radiating patches and the power distribution to each patch is arranged such that radiated energy from the patches sums at the reflector surface to produce the predetermined field distribution and polarization.

Abstract: A method is provided for transmitting and/or receiving files via a facsimile machine or computer fax modem. Electronic binary files residing on a computer, for example executable files, word processing files, database files and other types of files are converted to a machine readable binary bitmap in the form of a black and white bar code. Preferably the converted file is encrypted before being transmitted and printed. A receiving computer fax modem or facsimile machine can then print the file for later retransmission or storage, or a computer fax modem can reconstruct the file so that it can be used and/or executed after being received.