Abstract: A method and a system for calibrating at least one antenna (1,1-1,3. 1,j). At least a first antenna (1,4) within a first antenna array (102) can be selected as a primary reference antenna. At least one antenna (4,3) that is not within the first antenna array can be selected as a secondary reference antenna. At least a first signal propagation characteristic (122) can be measured based on at least one signal wirelessly communicated between the primary reference antenna and the secondary reference antenna. At least a second signal propagation characteristic (118) can be measured based on at least one signal wirelessly communicated between the secondary reference antenna and at least a second antenna (1,2) within the first antenna array. At least a first calibration coefficient can be determined for the second antenna.

Abstract: A method and a system for calibrating at least one antenna (1,1-1,3. 1,j). At least a first antenna (1,4) within a first antenna array (102) can be selected as a primary reference antenna. At least one antenna (4,3) that is not within the first antenna array can be selected as a secondary reference antenna. At least a first signal propagation characteristic (122) can be measured based on at least one signal wirelessly communicated between the primary reference antenna and the secondary reference antenna. At least a second signal propagation characteristic (118) can be measured based on at least one signal wirelessly communicated between the secondary reference antenna and at least a second antenna (1,2) within the first antenna array. At least a first calibration coefficient can be determined for the second antenna.

Abstract: A method, apparatus and system for performing over-the-air calibration routines in a multiple-input multiple-output (MIMO) communication system. An antenna array of a transceiver (e.g., transceiver of a base station) comprises a re-configurable antenna having two switchable configuration states. The antenna exhibits different degrees of electromagnetic coupling to other antennas of the array in a first state than in a second state. The reference antenna is switched to the first state for performing uplink/downlink calibrating transmissions and switched to the second state during uplink and downlink communications or channel sounding calibrating transmissions.

Abstract: A method and apparatus for performing beamforming are provided herein. During operation, a mobile device will notify a base station of the situation in which one or more of its antennas has become unusable. Using this technique, the Multiple Input, Multiple Output (MIMO) algorithms employed at the base station will be adjusted accordingly.

Abstract: A passive repeater includes: a connecting transmission circuit having first and second opposing ends and made of a flexible material for substantially conforming to a portion of a structure, the structure having first and second opposing sides; first and second antenna elements respectively coupled to the first and second opposing ends of the connecting transmission element; and first and second affixing elements respectively coupled to the first and second antenna elements for attaching the first and second antenna elements to the first and second opposing sides of the structure, wherein the first and second antenna elements are operable to transfer a signal from the first opposing side of the structure to the second opposing side of the structure via the connecting transmission circuit.

Abstract: A wireless communication device (100, 400) that can include a first electrically conductive structural member (102), a second electrically conductive structural member (104), and at least a first electrical conductor (118) that electrically connects a first portion (120) of the first structural member to the second structural member. A distance between the first portion and a second portion (122) of the first structural member can be selected to present a desired input impedance for an RF signal applied at the second portion of the first structural member. The distance can be approximately one-quarter of a wavelength of the RF signal or an odd multiple of the one-quarter wavelength. In another arrangement, the distance can be approximately one-half of a wavelength of the RF signal or a multiple of the one-half wavelength.

Abstract: A method and apparatus for recovering from cognitive radio errors are disclosed. The method may include receiving stamp data relating to a cognitive radio from the cognitive radio's database, the stamp data including time, location and sensor information, comparing the received stamp data with information stored in a master database, determining, based on the comparison, whether the cognitive radio's database is corrupt, wherein if the cognitive radio's database is corrupt, downloading a copy of the master database to the cognitive radio.

Abstract: A multiple band antenna has an RF coupling structure (110) and a resonant RF structure (102). The RF coupling structure (110) has an RF connection (116, 118) and an RF coupling end (112, 114). The resonant RF structure (102) is reactively coupled to the RF coupling end (112, 114). The resonant RF structure (102) has a first end (106) and a second end (108) and has a conductive perimeter (102) enclosing at least one slot area (104) configured to induce an additional resonant RF band for the resonant RF structure (102). The first end (106) and the second end (108) are reactively coupled to a ground plane (124, 120) to facilitate longer wavelength operation. Cellular phones (800) and wireless communications sections incorporating such antennas are also provided.

Abstract: A material properties detection system (100). The system can include an antenna (120) that is tuned for operation within a frequency band over which the antenna transmits. The system also can include a transmitter (210) that generates electromagnetic energy across the frequency band and forwards the electromagnetic energy to the antenna. An impedance measurement circuit (215) can be provided. The impedance measurement circuit can measure an input impedance of the antenna over the frequency band and generate measured impedance data (225). The system can include a material characterization application (230) that processes the measured impedance data to generate a material characterization for a structure (110) to which the antenna is proximate. The material characterization can include a dielectric constant, a permittivity, a loss tangent and/or a permeability.

Abstract: Wireless communication systems (100, 800) comprise mobile units (118, 802) provided with a directional coupler (206) and circuit (220) for measuring the complex reflectance (phase and magnitude) of antenna (202) of the mobile units (118, 802). The system (100, 800) has, either in the mobile unit (118, 802) or elsewhere, a processor (238, 808) programmed to perform pattern recognition of the near field environments of the mobile units (118, 802) by using the complex reflectance measurements as feature vectors. Information as to the near field environment at the time of wireless connection drops is suitably accumulated and is used in network upgrade planning and/or mobile unit design evaluation. The complex reflectance is alternatively used to discriminate antenna faults. Alternatively, near field environments that tend to degrade wireless communication performance are detected by the mobile unit using the complex reflectance and the mobile unit then alerts the user.