2472 results about "Multiple antenna" patented technology

A method for transmitting channel status information (CSI) of downlink multi-carrier transmission includes generating the CSI including at least one of a rank indicator (RI), a first precoding matrix index (PMI), a second PMI and a channel quality indicator (CQI) for one or more downlink carriers, the CQI being calculated based on precoding information determined by a combination of the first and second PMIs, determining, when two or more CSIs collide with one another in one uplink subframe of one uplink carrier, a CSI to be transmitted on the basis of priority, and transmitting the determined CSI over a uplink channel. If a CSI including an RI or a wideband first PMI collides with a CSI including a wideband CQI or a subband CQI, the CSI including a wideband CQI or a subband CQI has low priority and is dropped.

The present invention provides a compact antenna system having multiple antennas exhibiting polarization and pattern diversity. The system comprises at least two antennas which may have different polarizations, operatively coupled to a passive element which operates as a Balun for a first antenna and which is configured to absorb and re-radiate electromagnetic radiation from the second antenna to produce a desired radiation pattern. The present invention also provides for additional antennas operatively coupled to the passive element or to the first antenna to provide additional diversity.

A system and method are described for compensating for frequency and phase offsets in a multiple antenna system (MAS) with multi-user (MU) transmissions (“MU-MAS”). For example, a method according to one embodiment of the invention comprises: transmitting a training signal from each antenna of a base station to one or each of a plurality of wireless client devices, one or each of the client devices analyzing each training signal to generate frequency offset compensation data, and receiving the frequency offset compensation data at the base station; computing MU-MAS precoder weights based on the frequency offset compensation data to pre-cancel the frequency offset at the transmitter; precoding training signal using the MU-MAS precoder weights to generate precoded training signals for each antenna of the base station; transmitting the precoded training signal from each antenna of a base station to each of a plurality of wireless client devices, each of the client devices analyzing each training signal to generate channel characterization data, and receiving the channel characterization data at the base station; computing a plurality of MU-MAS precoder weights based on the channel characterization data, the MU-MAS precoder weights calculated to pre-cancel frequency and phase offset and / or inter-user interference; precoding data using the MU-MAS precoder weights to generate precoded data signals for each antenna of the base station; and transmitting the precoded data signals through each antenna of the base station to each respective client device.

Fiber, cable, and wireless data channels are typically impaired by reflectors and other imperfections, producing a channel state with echoes and frequency shifts in data waveforms. Here, methods of using OTFS pilot symbol waveform bursts to automatically produce a detailed 2D model of the channel state are presented. This 2D channel state can then be used to optimize data transmission. For wireless data channels, an even more detailed 2D model of channel state can be produced by using polarization and multiple antennas in the process. Once 2D channel states are known, the system turns imperfect data channels from a liability to an advantage by using channel imperfections to boost data transmission rates. The methods can be used to improve legacy data transmission modes in multiple types of media, and are particularly useful for producing new types of robust and high capacity wireless communications using non-legacy OTFS data transmission methods.

An antenna assembly includes a common reflector and multiple monopole type antenna elements positioned on a ground plane and fed with a switch assembly. The switch assembly is capable of feeding individual antennas as well as combining multiple antennas for improved radiation pattern coverage. Multiple antenna elements are placed around the common reflector to cover sectors of space around the antenna assembly to provide transmission and reception of radio frequency (RF) signals for mobile communication devices in a wireless network. The ground plane can be grounded or capacitively coupled to an existing circuit board or metal surface, allowing for reduced ground plane dimensions.

A method and system performs antenna tuning using detected changes in antenna self-capacitance in a wireless communication device. A modem detects changes in antenna self-capacitance by utilizing multiple antenna elements. The modem determines a current antenna loading condition using the detected changes in antenna self-capacitance. The modem determines appropriate tuning states for each antenna matching and tuning circuit (AMTC) associated with a respective antenna element. In order to determine the appropriate tuning states, the modem utilizes pre-established antenna self-capacitance information which is mapped to antenna tuning states. The antenna tuning states which are respectively mapped to pre-established antenna self-capacitance are empirically pre-determined by correlating antenna self-capacitance changes to antenna impedance changes. The modem is thus able to change the tuning states of multiple tunable matching circuits and perform antenna tuning using (a) detected real-time changes in antenna self-capacitance and (b) pre-established mappings of antenna self-capacitance and antenna tuning states.

Methods and apparatus are provided for communicating data in a multiple antenna communication system having N transmit antennas. According to one aspect of the invention, a header format includes a legacy preamble having at least one legacy long training field and an extended portion having at least N additional long training fields on each of the N transmit antennas. The N additional long training fields may be tone interleaved across the N transmit antennas and are used for MIMO channel estimation. The extended portion may include a short training field for power estimation. The short training field may be tone interleaved across the N transmit antennas and have an extended duration to support beam steering.

Methods and apparatus are provided for improved long preamble formats in a multiple antenna communication system having N antennas. According to one aspect of the invention, a preamble having a legacy portion and a high throughput portion is transmitted (or received) on each of the N transmit antennas, wherein the legacy portion comprises a legacy long training field and the high throughput portion comprises at least N high throughput long training fields, wherein the N high throughput long training fields are transmitted in N time slots using an N×N orthogonal matrix. The orthogonal matrix can be, for example, one or more of a Walsh matrix and a Fourier matrix. The N time slots can optionally comprise a single symbol.

An antenna assembly includes a common reflector and multiple monopole type antenna elements positioned on a ground plane and fed with a switch assembly. The switch assembly is capable of feeding individual antennas as well as combining multiple antennas for improved radiation pattern coverage. Multiple antenna elements are placed around the common reflector to cover sectors of space around the antenna assembly to provide transmission and reception of radio frequency (RF) signals for mobile communication devices in a wireless network. The ground plane can be grounded or capacitively coupled to an existing circuit board or metal surface, allowing for reduced ground plane dimensions.

An RFID reader is provided that includes an antenna array comprising multiple antenna elements circumferentially distributed around a longitudinal axis of the antenna array. Each antenna element includes multiple patch elements disposed above one or more underlying substrates, wherein the patch elements of each antenna element are disposed on an outer side of the antenna element. Further, one or more of the antenna elements is an asymmetric antenna element, wherein a first end of the asymmetric antenna element is wider than a second, opposite end of the asymmetric antenna element, wherein a first patch element disposed proximate to the first end of the asymmetric antenna element is larger than a second patch element disposed proximate to the second end of the asymmetric antenna element, and wherein a resonant frequency associated with the first patch element is approximately the same as a resonant frequency associated with the second patch element.

An apparatus and method for cooperative relay in a multiple-antenna wireless communication system based on relay stations (RSs) are provided. The apparatus includes a serial / parallel converter for dividing data into N number of streams, a channel estimator for calculating a first transmission rate at which a RS performing the cooperative relay can perform decoding and a second transmission rate at which all relay stations performing the cooperative relay can commonly perform decoding, and determining transmission rates for each of the N-number streams, and an adaptive modulation and coding (AMC) unit for encoding and modulating the N-number streams according to their respective transmission rates.

Methods and apparatus for high throughput wireless cells, capable of functioning as access points, are described. The wireless cells may be equipped with multiple radios to increase the amount of throughput available through a single wireless cell. Multiple antennas attached to the radios through RF switches may enable the wireless cell to service multiple clients simultaneously. The physical sectors of the antennas may overlapped to form virtual sectors that provide greater flexibility in client load management and in simultaneously servicing multiple clients. Attenuators may reduce interference from foreign wireless cells or clients. Systems and methods for assigning minimally interfering channels to either physical sectors or to radios to reduce interference between adjacent sectors and overlapping sectors are also disclosed. An antenna horn may also allow any antenna to be used as a directional antenna and may enable the antenna's angle of coverage to be adjusted. The use of multiple antennas on a client to reduce interferences is also described.

A system and method are provided to increase data rates available in mmWave wireless communication systems by adapting a multiple-input multiple-output (MIMO) in a next generation mmWave wireless communication system. The system and method advantageously employ the characteristics of mmWave antenna arrays, including multiple antenna elements in each antenna array, to implement the MIMO scheme by establishing multiple beamformed communication links between a mmWave transmitter and receiver. An outgoing signal is divided into multiple signal elements to correspond to the multiple beamformed links and each of the multiple signal elements is transmitted by the transmitter across a different one of the multiple beamformed links to be reassembled at the receiver. An antenna element allocation scheme is incorporated to assign specific numbers and configurations of antenna elements at each of the transmitted and receiver to each of the multiple beamformed communication links.