Abstract: An orthogonal frequency division multiplexing (OFDM) transmitter method, consistent with certain embodiments of the present invention arranges OFDM data symbols representing data bits for transmission in a packet. A prescribed pattern of OFDM data symbols are removed (212) and replaced (216) with pilot symbols. The packet is then transmitted (220) to an OFDM receiver that receives the packet (224) and determines a channel correction factor from the pilot pattern. The receiver then estimates a plurality of channel correction factors, one for each of the plurality of OFDM symbols representing data (228) and uses these correction factors to correct the OFDM symbols representing data (232). Arbitrary data are then inserted in place of the pilot symbols (236). The OFDM symbols representing data along with the arbitrary data are then decoded using an error correction decoder that corrects the errors induced by substitution of the pilot symbols for data symbols (240).

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: 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: 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: An orthogonal frequency division multiplexing (OFDM) transmitter method, consistent with certain embodiments of the present invention arranges OFDM data symbols representing data bits for transmission in a packet. A prescribed pattern of OFDM data symbols are removed (212) and replaced (216) with pilot symbols. The packet is then transmitted (220) to an OFDM receiver that receives the packet (224) and determines a channel correction factor from the pilot pattern. The receiver then estimates a plurality of channel correction factors, one for each of the plurality of OFDM symbols representing data (228) and uses these correction factors to correct the OFDM symbols representing data (232). Arbitrary data are then inserted in place of the pilot symbols (236). The OFDM symbols representing data along with the arbitrary data are then decoded using an error correction decoder that corrects the errors induced by substitution of the pilot symbols for data symbols (240).

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: The apparatus includes a memory for storing representations of a microcellular transmitter and a macrocellular transmitter. The representation of the microcellular transmitter is configured to transmit a representation of a first signal, the representation of the macrocellular transmitter is configured to transmit a representation of a second signal. A database is responsive to the memory. The database has a plurality of data structures, and the plurality of data structures comprise a map of a geographic area. A predetermined location is positioned on the map. A facet having a size and comprising at least three points defining a plane is associated with the predetermined location. First and second instruction sets are available to calculate a characteristic of the first and second signals. A processor responsive to the memory and the database uses one of the first instruction set and the second instruction set to calculate the characteristic at the predetermined location.