Abstract: A wireless access unit (12) for providing an interface between a satellite communications system (32) and a plurality of terrestrial user devices (14-26) in a centralized or distributed architecture includes a spectrum allocation unit (92) for dynamically allocating spectrum to the plurality of terrestrial user devices (14-26) based on a spectral environment about the wireless access unit (12). A spectrum scan unit (60) scans the spectral environment about the wireless access unit (12) and generates a spectrum signal indicative thereof. An environment understanding unit (61) provides signal information corresponding to signal emitters in proximity to the distributed or centralized network. A spectrum table (90) assembles data related to the spectral environment and the proximity emitters for use by the spectrum allocation unit (92) in dynamically allocating spectrum.

Abstract: A system (8) for digital processing of optical image data includes a wavelet decomposition unit (12) for decomposing an input image (10) into a plurality of frequency subbands. Each subband is then converted to a frequency domain representation, phase scrambled, and then converted back into a time domain representation in a phase scrambling unit (14). The subbands are then subject to trellis coded quantization (TCQ) in a trellis coded quantization encoding unit (16, 40) before being transmitted into a channel (28). In one embodiment, fixed rate trellis coded quantization (FRTCQ) is used in a communications system having a relatively noiseless channel.

Abstract: An information transfer system (ITS) (10) is capable of providing interoperability among a large number of external communications systems that each use different signal formats. The ITS (10) includes a group of interface units having a plurality of wireless interface units (12a-12n) for converting between a plurality of wireless signal formats and a common signal format and a plurality of wired interface units (14a-14n) for converting between a plurality of wired signal formats and the common signal format. In addition, the ITS (10) includes a switch (16) for selectively establishing connections between interface units in the group of interface units. Some or all of the interface units are dynamically reconfigurable for supporting new or changing signal formats.

Abstract: An adaptive arrangement and method for the coded digital transmission of images includes an adaptive transmitter (101) having an image coder (109) which is operable at multiple image coding rates, a channel coder (111) which is operable at a plurality of channel coding rates, and is further operable to provide a plurality of power outputs, baud rates, and a plurality of image delivery rates. The transmitter (101) further includes a channel status monitor (115) which monitors the communication channel (105) connecting the transmitter (101) to a receiver (103). The channel status monitor (115) responds to changes in the quality of the communications channel by varying one or more of the image coding rate, the channel coding rate, the power, the baud rate, and the image delivery rate.

Abstract: The invention relates to a communication system (300) having a receiver (304) that is capable of performing targeted interference suppression. An interference classifier (314) within the receiver (304) analyzes a signal received from a channel (306) and identifies and classifies interference components within the signal. An interference suppressor (316) then suppresses the interference components in the signal based on interference type. In one embodiment, the interference suppressor (316) includes a plurality of interference suppression modules that are each optimal for suppressing certain interference types. The interference suppressor (316) selects one of the interference suppression modules based on the type of interference present in the received signal. In another embodiment, a hybrid interference mitigation system (10) is provided by combining targeted interference suppression, frequency hopping adaptation, and processing gain adaptation.

Abstract: The invention relates to a communication system (300) having a receiver (304) that is capable of performing targeted interference suppression. An interference classifier (314) within the receiver (304) analyzes a signal received from a channel (306) and identifies and classifies interference components within the signal. An interference suppressor (316) then suppresses the interference components in the signal based on interference type. The interference suppressor (316) includes a plurality of interference suppression modules that are each optimal for suppressing certain interference types. In one embodiment, one or more of the interference suppression modules perform interference suppression using modal moment estimates to identify different modes within the signal.

Abstract: The invention relates to a communication system (300) having a receiver (304) that is capable of performing targeted interference suppression. An interference classifier (314) within the receiver (304) analyzes a signal received from a channel (306) and identifies and classifies interference components within the signal. An interference suppressor (316) then suppresses the interference components in the signal based on interference type. In one embodiment, the interference suppressor (316) includes a plurality of interference suppression modules that are each optimal for suppressing certain interference types. The interference suppressor (316) selects one of the interference suppression modules based on the type of interference present in the received signal. In another embodiment, a hybrid interference mitigation system (10) is provided by combining targeted interference suppression, frequency hopping adaptation, and processing gain adaptation.

Abstract: A communications network (10) having a plurality of wireless nodes (12-28) distributed within a region of interest makes routing decisions based on terrain information for the region of interest. A link quality determination unit (54) determines the quality of individual node-to-node links within the network (10), based on the location of the nodes (12-28) and the terrain about the nodes (12-28). A path selection unit 58 then determines an optimal path through the network 10 based on the link quality information. In one embodiment, communications corridors (102) are defined as preferred subpaths within a network for use in connecting remote nodes.

Abstract: A direct conversion receiver (DCR)(10) comprises amplitude modulated interference (AMI) nulling circuitry (32) for achieving enhanced cancellation of AMI. The AMI nulling circuitry (32) includes a first signal processor (42) and a second signal processor (44) for processing first and second differential output signals, respectively, from a mixer (24a). The first signal processor (42) includes an adjustable transfer function that is controlled by a controller (50). The controller (50) adjusts the transfer function of the first signal processor (42) to equalize the magnitudes of AMI components in the first and second differential output signals. The first and second differential output signals are then combined in a manner which cancels the equalized AMI components.

Abstract: The present invention relates to a communications system (100) that is capable of adapting to an unknown or varying spectral environment in a channel (14) between two communications units (12, 16). The system (100) maintains a spectral profile of the channel (14) and uses the spectral profile to determine appropriate transmit parameters for the system (100). The system (100) can be programmed to provide an optimal transmit signal for achieving a predetermined performance goal (such as, for example, maximum data rate at a given bit error rate (BER)) in light of the spectral environment in the channel (14). In one embodiment, the spectral profile is maintained in a spectrum table memory (27) that is periodically (or continuously) updated.

Abstract: A fast Fourier transformer (160) includes an FFT engine (162) having a twiddle index input and a memory bus coupled to a data input (167), a memory (164) coupled to the memory bus, an address generator (163) coupled to the memory (164), a twiddle index generator (150) including an output coupled to the twiddle index input, a counter (161) having an output coupled to inputs of the twiddle index generator (150) and the address generator (163) and a data output (168) coupled to the FFT engine (162) and to the memory (164).

Abstract: A communicator (10) includes a plurality of reconfigurable resource units (13) that can each be dynamically altered to perform any of a multitude of processing tasks. A controller (16) determines a plurality of processing tasks to be supported by the communicator (10) and configures the plurality of reconfigurable resource units (13) accordingly. A memory (18) stores a library of configuration files for use by the controller (16) in configuring the plurality of reconfigurable resource units (13). In one embodiment, the controller (16) continuously adapts the plurality of reconfigurable resource units (13) according to present system requirements.

Abstract: A secure, portable position locating radio has a geolocation receiver providing local position and timing information from geolocation means (e.g. GPS satellites) and a local transceiver for sending local position information to a communication system (e.g., an airborne or orbiting transceiver). A crypto unit is provided between the receiver and local transceiver for encrypting the local position information prior to transmission. A data processor coupled to the local transceiver, receiver and crypto unit controls operation of the device, including storing local position information and separating signals broadcast by the communication system into those intended or not intended for the device. An external interface and display and a real-time clock (e.g., slaved to the GPS receiver) are also coupled to the data processor. Encryption keys and message abbreviation codes are conveniently loaded into the device from a demountable accessory unit at the interface, and stored therein.

Abstract: A local traffic signal controller (3) is interfaced to a conventional pager (16) to provide for centralized control of the traffic signals controlled by the local controller. The central controller (7) may use the existing pager infrastructure (12) to provide for the transfer of program control information to local controllers. A two-way pager may be utilized to provide for the return of information from the local traffic signal controller. Such return information may include indications of lamp failures, traffic pattern information and other status or traffic related information.

Abstract: A secure, portable position locating radio has a geolocation receiver providing local position and timing information from geolocation means (e.g. GPS satellites) and a local transceiver for sending local position information to a communication system (e.g., an airborne or orbiting transceiver). A crypto unit is provided between the receiver and local transceiver for encrypting the local position information prior to transmission. A data processor coupled to the local transceiver, receiver and crypto unit controls operation of the device, including storing local position information and separating signals broadcast by the communication system into those intended or not intended for the device. An external interface and display and a real-time clock (e.g., slaved to the GPS receiver) are also coupled to the data processor. Encryption keys and message abbreviation codes are conveniently loaded into the device from a demountable accessory unit at the interface, and stored therein.

Abstract: A waveguide feed is fabricated by first creating a lead frame (10) from a piece of conductive material. The lead frame (10) is shaped by bending arms (22) and probe portions (18) on the lead frame (10) into a desired shape. The lead frame (10) is then placed in a mold and dielectric molding material is added around relevant portions of the lead frame (10). After the dielectric molding material has solidified, excess molding material and extraneous portions of the lead frame (10) are removed from the molded feed assembly. The assembly can then be connectorized and inserted into a waveguide.

Abstract: A system for a pipeline cascaded content addressable memory CAM system for sequentially processing input data includes an input register, a CAM core, cascade logic and an output register. As the memory association functions produce matches in the CAM core, the cascade logic in parallel composites data associated with each matching CAM core. Each cascade processes a separate data input simultaneously then passes on the cumulative results to the next stage.

Abstract: A method and system simplifies and accomplishes the programming of a PED (12), such as a cellular telephone (22), via the use of a personal computer (PC). The present invention includes software (52, 54) within the PC (14) for providing a graphical user interface (GUI) to the user for ease and simplicity of selecting various programming features and settings associated with the cellular telephone to be programmed. The software further includes a translator (56) for translating these user selected features/settings into specific key depresses to be sent to the cellular telephone, via software and hardware interfaces (58, 18, 20), for accomplishing the programming of such features/settings. Additionally, the software includes the capability to monitor the data being displayed on the cellular telephone because such data may be required to accomplish various programming features.

Abstract: A GPS based search and rescue system utilizes an airborne interrogation unit for extending the range of a second interrogation unit. The airborne unit relays communication between a survival radio and the second interrogation unit. The second interrogation unit is typically a ground based unit and is arranged to provide GPS correction information to the survival radio. The normal line of sight communication between a survival radio and an interrogation unit is extended to an over the horizon communication path by utilizing the airborne interrogation unit as a relay for communications.

Abstract: The present invention encompasses a method of storing ternary data that includes the steps of (1) initializing a conversion register by storing binary-to-ternary mask data in a conversion register; (2) storing ternary data in a content addressable memory (CAM) by inputting a single bit binary data to the conversion register, and converting the binary data into two bits of ternary data using the conversion register; and (3) simultaneously storing the two bits of ternary data in first and second memory cells. For subsequent searching, the method further includes the steps of searching for a match of input search binary data to the stored contents of the CAM; providing a match valid output responsive to the input search binary bits matching any of the stored contents; and generating an address corresponding to a location in the CAM where the match is found.