Abstract: A hydrogen getter device includes a package made from a material that is hydrogen permeable and moisture impermeable. A preferred hydrogen getter is a particulate zeolite having a portion of its sodium ions exchanged by an activated metal, such as silver. The package can be a flexible enclosure made from the hydrogen permeable moisture impermeable sheet material and surrounded by a porous protecting material. In one embodiment, the package includes an internal wall to define a first enclosure containing the hydrogen getter and a second enclosure containing a moisture absorbing agent or desiccant, such as a zeolite. The package is suitable for use in electrical enclosures having an internal volume of about 5 liters to about 100 liters or more.

Abstract: A method and apparatus for performing satellite selection in a broadcast communication system is provided. In some embodiments, a controlling data stream broadcast on a first satellite over a broadcast channel is utilized to indicate that information signals such as a television program are being carried on the same channel on a different satellite. Remote receiving apparatus utilize the controlling data stream to locate the information signals by switching to the satellite identified in the controlling data stream.

Abstract: The present invention is a method for generating short, non-systematic, non-linear (6,4) codes that may be implemented in a 4-ARY quadrature-quadrature phase shift keying (QQPSK or Q2PSK) system over GF(16). The codewords are non-systematic in that they do not directly contain the information that is to be transmitted and six symbols are sent to represent four symbols. The present invention uses a code construction method that generates two small, hand-optimized codeword sets and combines those two codeword sets to create two larger codeword sets. The two larger codeword sets are then combined to create a codeword set that is stored in a look-up table for use at a transmission station.

Abstract: A waveform to be transmitted as a burst within a channel that is used for the synchronization of unsynchronized wireless communications terminals in a wireless communications system, and a method of synchronization involving the waveform, that consists of a composite waveform. The composite waveform comprises two or more component waveforms, wherein each of the two or more component waveforms has a known frequency variation throughout the burst. The composite waveform has a composite bandwidth on an order of an available channel bandwidth and each of said two or more component waveforms have a component bandwidth on the order of the available channel bandwidth. Furthermore, a range of values for the differences between the instantaneous frequencies of two of said two or more component waveforms is on an order of twice of said available channel bandwidth.

Abstract: Encoding of prototype waveform components applicable to GeoMobile and Telephony Earth Station (TES) providing improved voice quality enabling a dual-channel mode of operation which permits more users to communicate over the same physical channel. A prototype word (PW) gain is vector quantized using a vector quantizer (VQ) that explicitly populates the codebook by representative steady state and transient vectors of PW gain for tracking the abrupt variations in speech levels during onsets and other non-stationary events, while maintaining the accuracy of the speech level during stationary conditions. The rapidly evolving waveform (REW) and slowly evolving waveform (SEW) component vectors are converted to magnitude-phase. The variable dimension SEW magnitude vector is quantized using a hierarchical approach, i.e., a fixed dimension SEW mean vector computed by a sub-band averaging of SEW magnitude spectrum, and only the REW magnitude is explicitly encoded.

Abstract: A facsimile transmission relay apparatus, referred to as an Intelligent Facsimile Relay (IFR) for improving call success rates in long delay environment such as terrestrial cellular, fixed wireless, and geostationary mobile satellite systems and the like. A first bi-directional telecommunications interface is provided for receiving facsimile signals from a transmitting facsimile device via a first network such as a Public Switch Telephone Network (PSTN). A buffer memory is used by the IFR for storing the facsimile signal, and a second bi-directional telecommunications interface retransmits the facsimile signal via the second network, e.g., a wireless network, to a receiving facsimile device to avoid signal collisions between the devices.

Abstract: A printed circuit board assembly includes a printed circuit board, with a first side and a second side and at least one opening formed therebetween. The opening has a slug at least partially disposed therein and attached to the first side. The second side of the circuit board has a hot component positioned thereon and overlying the opening. A solder joint is formed between the slug and the hot component to allow dissipation of heat from the hot component.

Abstract: An apparatus and method is disclosed, utilizing a communications network (in this particular design, it is a GEM (Geo-Mobile) satellite system) to initialize a Global Positioning System (GPS) receiver (such one integrated into a handheld user terminal, or phone used within the communication network) to enable the GPS receiver to quickly acquire GPS satellite signals and perform positioning calculations. By systematically feeding the GPS receiver key pieces of information (GPS satellite trajectories, time estimate, position estimate, and additional positional references), the time to first fix (TTFF) of the GPS receiver can be drastically reduced.

Abstract: A system and method employing an improved data compression and decompression technique for use in a communication system Specifically, the system and method employs an improved YK algorithm which uses an appropriate form of the trie data structure for the parsing operation. With the use of this data structure, the parsing complexity using this data structure is essentially proportional to the data size, and hence is very fast. The improved YK algorithm also is capable of handling errors in data without getting into an ambiguous state or causing the hardware or software system to crash. Furthermore, the improved YK algorithm is also capable of parsing the data based on predefined frequency characteristics and predefined grammar. The improved YK algorithm also sequentially updates the grammar, while keeping the number of variables below a pre-defined limit. This changes the grammar gradually, and can potentially increase the compression efficiency.

Abstract: A method and apparatus for encoding data for transmission in a communication system provides increased efficiency in bandwidth utilization through higher data rates, lower error rates, lower power levels, and/or increased capacity. A set of orthogonal codes is partitioned into subsets. The data to be transmitted is partitioned into packets of bit sequences, each of which is mapped to an orthogonal code in an assigned subset. The number of members in a particular subset is determined by the relative transmission requirements of the data signal the subset will be used to encode.

Abstract: An improved apparatus and method for pointing a satellite dish to receive signals from a geo-synchronous satellite. An aperture cover is used to partially block electromagnetic radiation provide to a feed horn and power and/or signal quality measurements are taken with the aperture cover covering various portions of the feed horn opening. Based on these power and/or signal quality measurements, it is determined in what direction and what angle in that direction the satellite dish must be re-oriented to achieve optimal signal strength from a geo-synchronous satellite or other fixed position microwave source.

Abstract: A system and method for tracking a user. The system is adapted for use in a wireless communication system and creates a plurality of beams within a coverage area. A first beam is directed at a user in a first microcell and a number of additional beams illuminate microcells immediately adjacent the first microcell. The system is equipped with a mechanism for detecting movement of the user from the first microcell to one of the immediately adjacent microcells. On the detection of movement of the user, the system redirects the first beam from the first microcell to a second microcell, the second microcell being one of the adjacent microcells. In the illustrative embodiment, the system is implemented in a stratospheric platform based communication system including a hub adapted to communicate with a stratospheric platform. A transceiver and a phased array antenna are disposed on the platform to communicate with the hub and with the user. A second antenna is provided on the platform to communicate with the hub.

Abstract: A method and apparatus for determining the proper satellite communications service to be provided to a subscriber unit that may be integrated with the geographically defined service areas used in terrestrial cellular communications systems. The pre-existing geographically defined service areas are subdivided into quadrilateral tiles wherein each tile corresponds to a single service area. In addition, the tiles are mapped to a grid having a plurality of regularly spaced grid locations. A lookup table is created that references each grid location to the tiles that overlap the grid locations. The position of the subscriber unit and an approximated region of error within which the subscriber unit is likely to be located are used as input. The approximated region of error is mapped to the grid to identify the grid locations that align with the approximated region of error.

Abstract: A system and method employing an access terminal for maintaining discontinuous communications including a gateway receiver for receiving the discontinuous information, a radio frequency (RF) communication link via geosynchronous earth orbit satellite for conveying multiple communication channels using time division multiple access (TDMA), the access terminal initiating information communication with the receiver via at least one of the multiple communication channels. The access terminal further includes a memory for storing protocol processing information and a transmitter for establishing the radio frequency communication link to the receiver of the terrestrial gateway system. The access terminal memory provides for destroying of a signal pattern or protocol assigned to the access terminal by the gateway receiver or transmission of keep-alive bursts by the transmitter during periods of inactivity to maintain information communication with the receiver.

Abstract: An apparatus for providing a secure processing environment is disclosed. In one embodiment, the apparatus includes a read/write memory for storing encrypted information. It also includes a processor, a cipherer and an authenticator. The cipherer is in communication with the read/write memory for receiving encrypted information therefrom and is configured to decrypt the encrypted information into decrypted information to be returned to the memory for subsequent use by the processor. The authenticator authenticates the decrypted information prior to use by the processor and re-authenticates the information prior to re-encryption by the cipherer.

Abstract: A method and system for determining a position of an object utilizes two-way ranging and polystatic techniques. A first communication transceiver at a first known location provides a bidirectional communication path between the first communication transceiver and the object wherein the first communication transceiver transmits a first ranging signal to the object and the object transmits a second ranging signal to the first communication transceiver in response to the first ranging signal. The first communication transceiver further provides a first unidirectional communication path between the first communication transceiver and the object wherein the first communication transceiver performs one of transmitting a third ranging signal to the object and receiving a fourth ranging signal from the object.

Abstract: A message format and associated method for estimating the frequency and timing offset of a reference burst of a random access channel in a time-division multiple access communications system. A signal structure in which the continuous wave segment is split into two parts separated by some portion of the content of the random access channel burst is used to provide more precise frequency estimation. Iteration of separate frequency and timing estimation procedures is used to refine both estimates, as the individual estimation processes are more accurate when there is less error in the other parameter. Multiple hypothesis testing is used, in which more than one initial frequency estimate is carried through the iteration process, with thresholding to identify the best frequency offset. Reliable rejection of false ambiguities is achieved because the degradation in timing estimation, due to large frequency offsets, can be detected with thresholding.

Abstract: A method, and related apparatus, for detecting interference at a first communications terminal comprising establishing a communications link between the first communications terminal and a second communications terminal. Then monitoring a noise floor of the communications link over time, the noise floor representing a base level of noise present in the communications link and calculating a long term noise floor power level without interference in response to the monitoring of the noise floor of the communications link over time. Then monitoring a noise floor of a current communication through the communications link, representing a current level of noise present on the communications link and calculating a short term noise floor power level in response to the monitoring of the noise floor of the current communication through the communications link. Finally, comparing the short-term noise floor power level with the long term noise floor power level without interference.