Abstract: A method (600) and simulation tool (200) having enhanced accuracy and speed for simulation using ray launching in a mixed environment (20) by using adaptive ray expansion mechanisms can include a memory (204) coupled to a processor (202). The processor can select (602) a target area within the mixed environment and modify (604) the propagation properties of the adaptive ray expansion mechanisms according to characteristics classified for the target area. The processor can further classify characteristics for the target area by transmitting and reflecting rays for indoor building regions and for outdoor building regions. The number of bounces or a power level threshold assigned to a transmitted ray is a function of the environment where it propagates. The simulation tool can determine the target area or a region of interest by using a global positioning service device (230) externally attached to a device performing functions of the simulation tool.

Abstract: A system (100) and method (400) for improving Radio Frequency (RF) Antenna Simulation is provided. The method can include determining (402) a proximity of an antenna (250) to a scattering structure (210), determining (410) a switching distance to the scattering structure that establishes when to switch the antenna on (416) and off (418) from a composite antenna pattern to a free space antenna pattern, and predicting RF coverage of the antenna responsive to the switching. The switching distance can be a function of a material type and a surface geometry of the scattering structure and a wavelength of the antenna. The method can also include evaluating a sensory mismatch in the antenna, and using a composite antenna pattern corresponding to the sensory mismatch.

Abstract: A system (170) and method (300) for ray launching is provided. The system can include a transmitter (110) for successively launching a plurality of rays, and a receiver (120) for receiving transmission rays and reflection rays. A controller (141) can be included for selectively adjusting an angular spacing and eliminating rays in successive launches to focus an energy on the receiver. A method (430) of terminating rays for reducing computational complexity is provided. A method (340) for ray weighting for increasing a computational speed of ray propagation is provided. In one aspect, a quality of service (108) can be determined at the receiver based on ray propagation.

Abstract: An Orthogonal Frequency Division Multiplexer (OFDM) transmitter and receiver apparatus consistent with certain embodiments of the present invention receives data to be transmitted and maps (204) a first portion of the data to a first polarization state and a second portion of the data to a second polarization state. A first transmitter (216) transmits the first portion of the data as a set of first OFDM subcarriers using an antenna (230) exhibiting a first polarization. A second transmitter (234) transmits the second portion of the data as a set of second OFDM subcarriers using an antenna (240) exhibiting a second polarization, wherein the first polarization is orthogonal to the second polarization. A receiver apparatus uses a first antenna (302) exhibiting the first polarization and a second antenna (306) exhibiting the second polarization.

Abstract: A method (20 or 500) and system (200) for method for computing wireless signal diffraction in a three-dimensional space can include the steps of selecting at least a source point, finding (19) sinkpoints that fail to have a line-of-sight path to the source point and storing the sinkpoints found, placing (21) diffraction points on all edges of a three-dimensional geometry, and building (24) a visibility matrix based on weighted paths for all source points and all sink points. The method can further include applying (25) a path finding algorithm on the visibility matrix for each sink point to all source points and storing store optimal paths for each source point to all sink points if they exist. The method can further include determining (23) if a last source point is selected before building the visibility matrix.

Abstract: A method (600) and simulation tool (200) having enhanced accuracy and speed for simulation using ray launching in a mixed environment (20) by using adaptive ray expansion mechanisms can include a memory (204) coupled to a processor (202). The processor can select (602) a target area within the mixed environment and modify (604) the propagation properties of the adaptive ray expansion mechanisms according to characteristics classified for the target area. The processor can further classify characteristics for the target area by transmitting and reflecting rays for indoor building regions and for outdoor building regions. The number of bounces or a power level threshold assigned to a transmitted ray is a function of the environment where it propagates. The simulation tool can determine the target area or a region of interest by using a global positioning service device (230) externally attached to a device performing functions of the simulation tool.

Abstract: A system (100) and method (400) for improving Radio Frequency (RF) Antenna Simulation is provided. The method can include determining (402) a proximity of an antenna (250) to a scattering structure (210), determining (410) a switching distance to the scattering structure that establishes when to switch the antenna on (416) and off (418) from a composite antenna pattern to a free space antenna pattern, and predicting RF coverage of the antenna responsive to the switching. The switching distance can be a function of a material type and a surface geometry of the scattering structure and a wavelength of the antenna. The method can also include evaluating a sensory mismatch in the antenna, and using a composite antenna pattern corresponding to the sensory mismatch.

Abstract: A method (10 or 500) and system (200) for simulating and improving accuracy of empirical propagation models for radio frequency coverage can include a display (210) and a processor (202) coupled to the display. The processor can be operable to input (502 and 504) low-resolution data and high-resolution data, select (506) an area of interest being simulated for empirical propagation models, and classify (508) receivers as belonging to a predetermined type of object. If a receiver in the area of interest is a low resolution object, then normal losses can be applied (510). If a receiver in the area of interest is a high resolution object, then losses specific to the high resolution object can be applied (512). If a receiver is classified as being inside a building, then the processor can further compute (516) a median power for a location of the receiver and add in-building penetration losses.

Abstract: A method (10) and system (200) for generating a high resolution database from low resolution databases introduces (12) a low resolution database and selects a desired area, classifies (16) portions of the desired area and geographically locates and generates (20) a new desired area based on a higher resolution setting than is found on the low resolution database. The method can further incorporate (22) the portions of the desired area that were geographically located in the new desired area and replaces (24) the portions of the desired area that were geographically located with a higher resolution object. The method can define (14) the low resolution database and identify (18) the higher resolution setting. The method can also save (26) a composite resolution database. The method can use an aerial image and its pixilation to create a higher resolution image by interpolation to form a higher resolution image.

Abstract: A system (170) and method (300) for ray launching is provided. The system can include a transmitter (110) for successively launching a plurality of rays, and a receiver (120) for receiving transmission rays and reflection rays. A controller (141) can be included for selectively adjusting an angular spacing and eliminating rays in successive launches to focus an energy on the receiver. A method (430) of terminating rays for reducing computational complexity is provided. A method (340) for ray weighting for increasing a computational speed of ray propagation is provided. In one aspect, a quality of service (108) can be determined at the receiver based on ray propagation.

Abstract: A technique is used in a wideband wireless communication system (100). In some embodiments available channels are determined (310) and one is selected (315) for assignment to each of a set of communication units based on a relative frequency path loss for each available channel. In some embodiments a communication unit is assigned (505) a channel selected from among available channels and a relative signal loss parameter of the communication unit, such as transmit power, is adjusted (510), based on a relative frequency path loss determined from the channel frequency of the assigned channel. In other embodiments, transmit information is split (705) into a plurality of data streams, each characterized by an associated relative signaling sensitivity, and each data stream is assigned (715) to one of a plurality of the transmit channels, wherein data streams are assigned channels of decreasing channel frequencies in order of decreasing associated relative signaling sensitivities of the data streams.

Abstract: A system and method for determining a most likely material composition of an object. At least one respective stored radiation polarization transformation is stored for at least one material composition at a plurality of wavelengths. A transmitted electromagnetic signal with at least one wavelength within the plurality of wavelengths and that has a predetermined transmitted polarization profile is transmitted. The transmitted signal encounters an object and is received as at least one received signal. Processing determines a respective received polarization for each of the at least one wavelength of the received signal, determines a respective calculated polarization transformation between the transmitted polarization profile and the received polarization of the respective wavelength, for each of the at least one wavelength.

Abstract: Communication systems include a transmitter that modulates a radio signal transmitted from two differently polarized antennas during a state time in which a wave state of the radio signal conveys information and is based on one or more polarization states selected from a constellation of polarization states comprising at least three polarization states. The communication system includes a receiver that intercepts the radio signal by two differently polarized antennas during the state time, and demodulates the signal. The polarization states may identify user devices or may quantify a portion of the information intended for a user device.

Abstract: An antenna system (205) includes an antenna structure (215), a receiver (220), and an antenna system controller (225). The antenna structure includes an arrangement of antennas (237), a signal combiner (240), and a switching matrix (235). The arrangement of antennas is designed to have a set of antenna element separations that are optimized to provide lowest correlation coefficients of intercepted radio signals for a corresponding set of electromagnetic environment types that vary from a very low density scattering environment to a maximum density scattering environment. The antennas (230), (231), (232), (233), (234) in the antenna arrangement each include at least one element that has a common polarization. There is at least one antenna that is a dual polarized antenna. The antenna system selects an antenna element pair that corresponds to the environment type which it is operating and thereby receives a best combined signal.

Abstract: A system and method for determining a most likely material composition of an object (102). At least one respective stored radiation polarization transformation (500) is stored for at least one material composition at a plurality of wavelengths. A transmitted electromagnetic signal (112) with at least one wavelength within the plurality of wavelengths and that has a predetermined transmitted polarization profile is transmitted. The transmitted signal (112) encounters an object (102) and is received as at least one received signal (116, 118). Processing determines a respective received polarization for each of the at least one wavelength of the received signal (116, 118), determines a respective calculated polarization transformation between the transmitted polarization profile and the received polarization of the respective wavelength, for each of the at least one wavelength,.

Abstract: A combined polarimetric and coherent processing receiver (2300) can include at least one antenna (730 and 740), at least one receiver front end (700 and 704), a multipath processor (702, 706, and 714), a polarimetric signal processor (708), and a coherent processor (712). The multipath processor can be a plurality of correlators (702 and 706) coupled to the receiver front end(s) and can process the desired signal arriving from multiple paths coupled to the receiver. The polarimetric signal processor which can include a plurality of adaptive polarimetric filters (710) can be coupled to the multipath processor and can polarimetrically filter signals that are distinguishable from the desired signal. The coherent processor can be coupled to the polarimetric signal processor and can coherently combine the polarimetric filtered signal. The coherent processor can include time varying complex coefficients (714) and a signal combiner (716).

Abstract: A communication device 10 and a corresponding method are arranged for changing the radiation pattern of an antenna 14, where the radiation pattern of the antenna 14 is set to a half-space pattern if the communication device 10 is in close proximity to an object. A reflector 18 is activated to produce the half space radiation pattern. The reflector 18 is deactivated to produce the full space pattern. A switching device 26 determines the state of the reflector 18. A sensing and control device 23 controls the state of the switching device 26.

Abstract: A technique is used in a wideband wireless communication system (100). In some embodiments available channels are determined (310) and one is selected (315) for assignment to each of a set of communication units based on a relative frequency path loss for each available channel. In some embodiments a communication unit is assigned (505) a channel selected from among available channels and a relative signal loss parameter of the communication unit, such as transmit power, is adjusted (510), based on a relative frequency path loss determined from the channel frequency of the assigned channel. In other embodiments, transmit information is split (705) into a plurality of data streams, each characterized by an associated relative signaling sensitivity, and each data stream is assigned (715) to one of a plurality of the transmit channels, wherein data streams are assigned channels of decreasing channel frequencies in order of decreasing associated relative signaling sensitivities of the data streams.

Abstract: A subscriber device (10) includes one or more sensors (102) for measuring a object electromagnetic characteristic, such as conductivity, permittivity or permeability. A controller (104) stores the object electromagnetic parameter in memory (106) and, operating in accordance with a performance enhancement routine stored in the memory (106), enhances operation of the subscriber device (10) in accordance with the electromagnetic parameter. The controller (104) may do this by adjusting the power of an amplifier (112), the frequency of a synthesizer (114) or the impedance of an antenna (110). A software program controlling the subscriber device and a corresponding method are described.

Abstract: An antenna system (205) includes an antenna structure (215), a receiver (220), and an antenna system controller (225). The antenna structure includes an arrangement of antennas (237), a signal combiner (240), and a switching matrix (235). The arrangement of antennas is designed to have a set of antenna element separations that are optimized to provide lowest correlation coefficients of intercepted radio signals for a corresponding set of electromagnetic environment types that vary from a very low density scattering environment to a maximum density scattering environment. The antennas (230), (231), (232), (233), (234) in the antenna arrangement each include at least one element that has a common polarization. There is at least one antenna that is a dual polarized antenna. The antenna system selects an antenna element pair that corresponds to the environment type which it is operating and thereby receives a best combined signal.