9587results about "Baseband systems" patented technology

Methods and apparatus for transmitting uplink control information (UCI) in carrier aggregated spectrums are disclosed. UCI may include, but is not limited to, Precoding Matrix Indicator (PMI), Rank Indication (RI), Channel Quality Indicator (CQI), Acknowledge / Not Acknowledge (ACK / NACK) and Scheduling Request (SR). For symmetric carrier aggregation, uplink (UL) and downlink (DL) component carriers may be paired and use physical uplink control channel (PUCCH) in each UL component carrier to send UCI for the corresponding DL component carrier. For asymmetric carrier aggregation, methods are provided for UCI transmission and resource allocation depending on component carrier configuration or assignment. Methods are provided for multiple and single component carrier configurations that may further provide backward compatibility.

The communication system of one embodiment is for communicating data through a power distribution system having a medium voltage power line and low voltage power line and comprises a first device comprising a first wireless transceiver, a first modem in communication with the first wireless transceiver and the medium voltage power line. The system may also comprise a second device comprising a second wireless transceiver in wireless communication with the first wireless transceiver; and a second modem in communication with the second wireless transceiver and the low voltage power line.

Coding techniques for a (e.g., OFDM) communication system capable of transmitting data on a number of "transmission channels" at different information bit rates based on the channels' achieved SNR. A base code is used in combination with common or variable puncturing to achieve different coding rates required by the transmission channels. The data (i.e., information bits) for a data transmission is encoded with the base code, and the coded bits for each channel (or group of channels with the similar transmission capabilities) are punctured to achieve the required coding rate. The coded bits may be interleaved (e.g., to combat fading and remove correlation between coded bits in each modulation symbol) prior to puncturing. The unpunctured coded bits are grouped into non-binary symbols and mapped to modulation symbols (e.g., using Gray mapping). The modulation symbol may be "pre-conditioned" and prior to transmission.

A system may perform interconnect BIST (IBIST) testing on source synchronous links. The system may perform, at normal operating frequency, a source synchronous link test that tests a victim line on the source synchronous link using a transition weave pattern. The transition weave pattern causes interaction between a data transition on the victim line, previous transitions on the victim line, and transitions on the other lines of the link (the “aggressor” lines). The interaction caused may be: (i) a first crossing pulse on the victim line; (ii) a second crossing pulse of the opposite polarity on each aggressor line concurrent with the first crossing pulse on the victim line; and (iii) a reflection in the opposite direction of the first transition of the first crossing pulse, wherein the reflection results from a previous transition on the victim line.

A method and apparatus for subcarrier selection for systems is described. In one embodiment, a method for subcarrier selection for a system employing orthogonal frequency division multiple access (OFDMA) comprises partitioning subcarriers into groups of at least one cluster of subcarriers, receiving an indication of a selection by the subscriber of one or more groups in the groups, and allocating at least one cluster in the one or more groups of clusters selected by the subcarrier for use in communication with the subscriber.

The present invention provides a system for operating a power line communications system that is comprised of a plurality of network elements, which may take the form of repeaters, bypass devices, backhaul devices, wireless backhaul devices, enhanced bypass device, communication interface devices and others. In one embodiment, two groups of network elements in the same electrical distribution system are isolated except selected communication link.

An adaptive multicarrier wireless communication system, apparatus and associated methods are generally disclosed herein.

A receiver in a wireless communication system comprises a reverse transform configured to produce a vector of baseband signal values, and a projection canceller configured to project the vector of baseband signal values onto at least one subspace that is substantially orthogonal to an interference subspace. The reverse transform may be adjoint to a forward transform employed by at least one transmitter in the wireless communication system. The combination of interference cancellation with one or more receiver operations may be a substantially adjoint operation relative to one or more transmitter operators and channel-propagation effects. The reverse transform may include a Fourier transform, a wavelet transform, or any other well known invertible transforms. Reverse transforms may include spread-spectrum multiple-access coding and may be implemented in systems configured to perform single-input, multiple output or multiple-input, multiple-output operations. Interference components may be selected in a projection canceller relative to predetermined ratios of interference in the received signal.

An apparatus is provided for high frequency multiplexed electrical line communication for cable TV, telephone, internet, security and other control applications over the mid and low voltage power lines and directly through the transformers. The apparatus includes a transmitter, a receiver, a modem, a multiplexer and multiple couplers at each of two or more locations along an electrical line. The couplers have capacitive circuits serially connected with an air-core or dielectric-core transformer. The capacitive circuits resonate with the transformer at a preselected frequency. The coupler eliminates noise and is matched to the characteristic impedance of the line at the preselected frequency, which linearizes communication on the line and allows high speed data and voice communication over long distances. Multiple modulators and demodulators are used to produce multiple modulated carrier frequencies.

A wireless communication includes a base station that configures a set of non-zero power reference signals corresponding to multiple potential transmission points to one or more users equipment UEs and configures at least one zero-power reference signal, with zero transmission power from one or more of the multiple transmission points. The base station transmits configuration information to at least one UE of the one more UEs, wherein the configuration information corresponds to a set of resource elements that are associated with a set of channel state information reference signals and wherein the set of channel state information reference signals include the set of nonzero-power reference signals and the at least one zero-power reference signal. The UE then performs a channel measurement based on one or more non-zero-power reference signals of the set of non-zero-power reference signals and performs an interference measurement based on the at least one zero-power reference signal.

A method for processing a Channel State Information Reference Signal (CSI-RS) in a wireless communication system based on a multiple access scheme is provided. The CSI-RS transmission method defines a plurality of CSI-RS patterns, assigns the CSI-RS patterns to individual cells, uses the CSI-RSs alternately per Physical Resource Block (PRB) so as to utilize the transmission powers of all antenna ports for transmitting CSI-RSs, transmits Coordinated Multi Point (CoMP) CSI-RSs and non-CoMP CSI-RSs separately, and mutes specific resources in association with the CSI-RS pattern of adjacent cells.

A intelligent backhaul radio have an advanced antenna system for use in PTP or PMP topologies. The antenna system provides a significant diversity benefit. Antenna configurations are disclosed that provide for increased transmitter to receiver isolation, adaptive polarization and MIMO transmission equalization. Adaptive optimization of transmission parameters based upon side information provided in the form of metric feedback from a far end receiver utilizing the antenna system is also disclosed.

A facility transport system for transporting high speed Ethernet data over digital subscriber lines. The system, referred to as 100BaseS, is capable of transmitting 100 Mbps Ethernet over existing copper infrastructure up to distances of approximately 400 meters. The system achieves bit rates from 25 to 100 Mbps in increments of 25 Mbps with each 25 Mbps increment utilizing a separate copper wire pair. Each pair used provides a bidirectional 25 Mbps link with four copper wire pair connections providing 4×25 Mbps downstream channels and 4×25 Mbps upstream channels. The system utilizes framing circuitry to adapt the 100BaseT input data signal to up to four separate output signals. A DSL Ethernet Port card couples the modem to each twisted pair used. Each DSL Ethernet Port card comprises modem transmitter and receiver circuitry for sending and receiving 100BaseS signals onto twisted pair wires. The system utilizes QAM in combination with frequency division multiplexing (FDM) to separate downstream channels from upstream channels and to separate both the downstream and the upstream channels from POTS and ISDN signals.

The communication system includes a hybride fiber / coax distribution network. A head end provides for downstream transmission of telephony and control data in a first frequency bandwidth over the hybrid fiber / coax distribution network and reception of upstream telephony and control data in a second frequency bandwidth over the hybrid fiber / coax distribution network. The head end includes head end multicarrier modem for modulating at least downstream telephony information on a plurality of orthogonal carriers in the first frequency bandwidth and demodulating at least upstream telephony information modulated on a plurality of orthogonal carriers in the second frequency bandwidth. The head end further includes a controller operatively connected to the head end multicarrier modem for controlling transmission of the downstream telephony information and downstream control data and for controlling receipt of the upstream control data and upstream telephony information. The system further includes service units, each service unit operatively connected to the hybrid fiber / coax distribution network for upstream transmission of telephony and control data in the second frequency bandwidth and for receipt of the downstream control data and telephony in the first frequency bandwidth. Each service unit includes a service unit multicarrier modem for modulating at least the upstream telephony information on at least one carrier orthogonal at the head end terminal to another carrier in the second frequency bandwidth and for demodulating at least downstream telephony information modulated on at least a band of a plurality of orthogonal carriers in the first frequency bandwidth. Each service unit also includes a controller operatively connected to the service unit multicarrier modem for controlling the modulation of and demodulation performed by the service unit multicarrier modem. A method of monitoring communication channels, a distributed loop method for adjusting transmission characteristics to allow for transmission of data in a multi-point to point communication system, a polyphase filter technique for providing ingress protection and a scanning method for identifying frequency bands to be used for transmission by service units are also included. Also provided is a method and apparatus for performing a Fast Fourier Transform (FFT). In one embodiment, a scalable FFT system is built using a novel dual-radix butterfly core.

A system and method for initializing a system communication without previous reservations for random access channel (RACH) access includes a first step of defining at least one spread sequence derived from at least one constant amplitude zero autocorrelation sequence. A next step includes combining the spread sequence with a Walsh code to form an extended spread sequence. A next step includes using the extended spread sequence in a preamble for a RACH. A next step includes sending the preamble to a BTS for acquisition. A next step includes monitoring for a positive acquisition indicator from the BTS. A next step includes scheduling the sending of a RACH message. A next step includes sending the RACH message.

An approach is provided for a method of encoding structure Low Density Parity Check (LDPC) codes. Memory storing information representing a structured parity check matrix of Low Density Parity Check (LDPC) codes is accessed during the encoding process. The information is organized in tabular form, wherein each row represents occurrences of one values within a first column of a group of columns of the parity check matrix. The rows correspond to groups of columns of the parity check matrix, wherein subsequent columns within each of the groups are derived according to a predetermined operation. An LDPC coded signal is output based on the stored information representing the parity check matrix.

Apparatus and methods are described that enable concurrent transmission of multiple data signals including clock, synchronization, and power over a single-wire bus between a master device and one or more slave devices. A first transmission channel from the master device to the slave device may modulate the width of periodic pulses between a first voltage level and a second voltage level with respect to a reference potential. A second transmission channel may modulate the amplitude of at least one of the first and second voltage levels to at least one third voltage level. Concurrent communications between a master device and one or more slave devices over a single-wire bus can be achieved.

a radio communication system which includes a base station apparatus and terminal apparatuses and performs TDD two-way communications using an OFDM signal including subcarriers in a downstream communication from the base station apparatus to each terminal apparatus, and an FH signal having the same frequency band as that of the subcarriers in an upstream communication from the each terminal apparatus to the base station apparatus, the each terminal apparatus estimates transmission channel characteristics of the subcarriers based on the OFDM signal received, transmits an estimation result of the estimation unit to the base station apparatus, and the base station apparatus assigns, to the each terminal apparatus, at least one of subcarriers to be used in the downstream communication of the subcarriers and a hopping pattern to be used in the upstream communication, based on the estimation result transmitted from the each terminal apparatus.

A power line coupler for communicating data signals over a power distribution system having a first and second overhead energized medium voltage power line conductors is provided. In one embodiment, the coupler includes a first lightening arrestor having a first end and a second end, wherein the first end of the first arrestor is connected to the first power line conductor. The coupler further includes a first high frequency impedance having a first end connected to the second end of the first lightening arrestor and the first impedance having a second end connected to a neutral conductor of the power line distribution system. The coupler may further include a second lightening arrestor having a first end and a second end, wherein the first end of the second arrestor is connected to the second power line conductor. The coupler further including a second high frequency impedance having a first end connected to the second end of the second lightening arrestor and a second end connected to the neutral conductor. The first high frequency impedance and the second high frequency impedance may each comprise an air core coil that forms an inductor. The coupler may further include a balun having a first winding and a second winding, wherein the first winding is coupled to a communication device, and wherein the second winding has a first end connected to the first end of the first high frequency impedance and a second end connected to the first end of the second high frequency impedance.

Reducing a power of a signal electromagnetically coupled from a PLC medium to a digital subscriber line (DSL) medium. The method involves transmitting a data signal over the PLC medium at a first average power level from one of a plurality of PLC transmitters coupled to the PLC medium, then measuring first noise associated with a first signal received at a DSL receiver coupled to the DSL communication medium caused at least in part by the data signal transmitted over the PLC medium at a second average power level from the one PLC transmitter, the second average power level different than the first average power level, followed by measuring second noise associated with a second signal received at the DSL receiver coupled to the DSL communication medium caused at least in part by the data signal transmission over the PLC medium at the second average power level. A transmit power spectral density (PSD) for the data signal transmitted by the one PLC transmitter over the PLC medium is then changed, based on a difference between the first noise and the second noise, such that the changed transmit PSD for the data signal transmitted by the one PLC transmitter over the PLC medium reduces the power of the signal electromagnetically coupled from the PLC medium to the DSL medium caused by the data signal transmission from the one PLC transmitter over the PLC medium.

In order to facilitate sending of different kinds of channel feedback information, a periodic information transmission in a shared uplink channel is configured, PUSCH, and required resources are allocated for the transmission.