Abstract: Soft decision decoding of a codeword of a Reed-Muller (RM) code by selecting an optimal decomposition variable i using a likelihood calculation. A code RM(r, m) is expressed as {(u, uv)|u?RM(r, m?1) and v?RM(r?1, m?1)) where uv denotes a component-wise multiplication of u and v, and (u, uv)=(r1, r2). A receive codeword is separated into r1=u and r2=uv based on the optimal decomposition variable, and r2 is decoded according to the optimal decomposition variable, using a RM(r?1, m?1) decoder to obtain a decoded v and a first set of decoded bits. The decoded v is combined with r1 using (r1+r2v)/2, and (r1+r2V)/2 is decoded using a RM(r, m?1) decoder to obtain a decoded u and a second set of decoded bits.

Abstract: An optical network includes multiple source, cross connect, and destination nodes. A traffic demand matrix is constructed for each possible pair of combinations of the source nodes and the destination nodes. A first energy reduction metric is determined for creating the bypass between the source node and any XC node based on the traffic demand matrix, and a second energy reduction metric is determined for creating the bypass between any XC node and the destination node using the traffic demand matrix. Then, a bypass that terminates at one of the XC nodes that has a largest energy reduction metric is created.

Abstract: A method estimates a wireless channel at a receiver. The signal is transmitted using narrowband orthogonal frequency division demultiplexing (OFDM) and frequency subcarriers, and the signal includes a set of data tones and a set of pilot tones. The channel and pilot tone interference are estimated based on all the pilot tones extracted from the signal and a channel model. The set of data are equalized based on the channel estimate. Data interference is detected according to the pilot interference and the equalized data tones. Subcarrier interference-to-noise ratios are determined based on the data interference. Signal strengths of the data tones are determined based on the equalized data tones, log-likelihood ratios of bits represented by the data tones are determined based on the subcarrier interference-to-noise ratios and the signal strength of the data tones.

Abstract: A set of symbols is encoded using a continuous mapping function to produce corresponding encoded functions, wherein the mapping function is continuous and values of the encoded functions are real and vary continuously. The encoded functions are summed in a spatial domain to generate a summed function, which is biased so that values of a biased function are all positive and real. Then, a physical property of the object is altered according the biased function to arrange a mark on the object.

Abstract: A network includes a transmitter and a receiver, wherein the transmitter includes a set of transmit antennas and the receiver includes a set of receive antennas. The transmitter duplicates a packet as copies of the packet, and selects subsets of the set of transmit antennas independent of channel characteristics between the subsets of transmit antennas and the set of receive antennas, wherein combinations of the antennas in the subsets of the transmit antennas are different. The receiver selects subsets of the set of receive antennas independent of channel characteristics between the subsets of receive antennas and the set of transmit antennas, wherein combinations of the antennas in the subsets of the receive antennas are different. The selected subsets are used to transmit the packet, and retransmit the packet in case of a failure in a previous transmission.

Abstract: A hybrid communication network for a transportation safety system includes a fixed wired nodes and mobile wireless nodes. Because the wired nodes operate independently packets transmitted by the wired nodes to the wireless nodes need to be synchronized. A downlink travel time for downlink packets traveling from a controller to the wireless nodes is determined. Then, the controller schedules downlink data intervals (DDI) based on the downlink travel time; and transmits downlink packets to the wireless nodes during the DDI, such that a latency requirement of the transportation safety system is satisfied.

Abstract: A hybrid communication network for a transportation safety system includes a wired network including a set of fixed nodes. Each fixed node includes a wired interface for connecting the fixed node to the wired network and at least one wireless interface. The set of fixed nodes further includes a head node at a first end of the wired network connected to a controller, a terminal node at a second end of the wired network, and a set of relay nodes arranged between the head node and the terminal node. A wireless network includes a set of mobile nodes and a set of fixed nodes connected to the wired network. Each mobile node includes at least one of the wireless interfaces, and each mobile node is arranged in a moveable car.

Abstract: In a network for a safety system in a transportation system, the transportation system includes a shaft and a car arranged in the shaft. A first wall node is at a first end of the shaft and a second wall node is at a second end of the shaft to communicate safety messages with the car. Each wall node includes at least one wireless transceiver connected to one or more antennas. Each car in the shaft includes at least two wireless transceiver connected to one or more antennas, wherein the first transceiver of the car uses a first frequency and the second transceiver of the car uses a second frequency to communicate each safety messages in duplicate. A wired backbone connects the set of wall nodes to a controller of the safety system of the transportation system.

Abstract: A road surface includes lane marking that store digital information. Images of the road surface and lane markings are acquired by a camera. The digital information is decoded from the images, analyzed so that a feedback signal can be generated according to the decoded digital information.

Abstract: A method and system broadcasts an alert packet in a wireless multi-hop network of nodes. An event is sensed in a source node of the network, and an alert packet is broadcast in response to sensing the event. The alert packet is received in a set of candidate nodes within a broadcast range of the source node. Each candidate node infers a distance between the candidate node and the source node based on a receive power of the received alert packet, and determines a priority for rebroadcasting the alert packet, wherein the priority is based on the distance to minimizing a probability of collisions while rebroadcasting the alert packet and extend a range of the rebroadcasting.

Abstract: A transmitter encodes an input bitstream using space-time trellis coding (STTC). The encoder includes a serial to parallel convertor to produce a first and second output bitstreams. First and second three bit shift registers are connected to produce first and second output bitstreams. A multiplier applies a code generating weight to each bit of the shift registers to encode the bitstreams. A first switch is connected between a last bit of the first shift register and a first bit of the second shift register. A second switch is connected between the second output and the first bit of the second shift register. The first set of encoded bit streams and the second set of encoded bitstreams are combined and mapped to a frequency domain.

Abstract: A location of an object is determined by arranging a sequence of bits on a substrate. The sequence of bits includes subsequence of bits, and each subsequence of bits is unique for each location along the substrate. When the object is at a particular location along the substrate a sensor detects the subsequence of bits at the particular location, and a decoder associates the location of the subsequence at the particular location with the object. The substrate can be a leaky coaxial cable with slits or not, corresponding to the bits, or lane markings on a road.

Abstract: A method performs handover of a mobile station (MS from a current base station (BSC) connected to a target base station (BST) via a backbone in a Worldwide interoperability for Microwave Access (WiMAX) mobile communication network. The MS, before handover, transmits a Connection Identifier Request (CID-REQ) to the BST via the BSC, and receiving a Connection Identifier Response (CID-RSP) from the BST via the BSC. The MS, before handover, transmits a Subscriber Station (SS) Basic Capability Request (SBC-REQ), and receives a SS Basic Capability Response (SBC-RSP) from the BST via the BSC. Then, the MS transmits a Ranging Request (RNG-REQ) to the BST, and receives a Ranging Response (RNG-RSP) from the BST. During the handover, the MS transmits a Registration Request (REG-REQ) to the BST, and receives a Registration Response from the BST to establish the connection between the MS and the BST.

Abstract: A method and network communicate packets by assigning, in each one of a set of multiple transmitters, a power level to a packet to be transmitted during a time interval. The power level is selected from a set of power levels available for the set of multiple transmitters. The power levels in the set range from highest to lowest. There is one packet for each transmitter such that there is a set of packets to be transmitted during the time interval. The set of packets is transmitted concurrently during the time interval to enable decoding of at least one of the packets in the set of packets during the time interval.

Abstract: A method predicts resource allocations in a wireless network including a set of base stations (BSs). Each BS is in a cell, and serves a set of mobile stations. A sequence and rule of resource allocations are defined for all of the BSs. Previous resource allocations are acquired from the BSs in adjacent cells. In each BS, for a next allocation, inter-cell interference (ICI) is predicted independently for the set of MSs in the cell based on the previous resource allocations by the BSs in the adjacent cells and the sequence and rule of resource allocations. Then, each BS allocates the resources to the MSs in the cell based on the ICI and the previous resource allocations.

Abstract: Beams are used to communicate in a wireless network including mobile and stationary receivers. The network operates according to the IEEE 802.11p in wireless access to vehicular environments (WAVE). A direction from the mobile transceiver to the stationary receiver is predicted using geographic information available to the mobile transceiver. A set of signals are received in the mobile transceiver from the stationary transceiver, wherein the signals are received by an array of antennas, and wherein the signals are received using a set of beams, and wherein each beam is approximately directed at the stationary receiver. A signal-to-noise ratio (SNR) is measured for each beam, and the beam with an optimal SNR is selected as an optimal beam for communicating data between the mobile transceiver and the stationary transceiver.

Abstract: A transmitter transmits data having a set of two or more priorities on subcarriers using orthogonal frequency division multiplexing (OFDM) symbols. The transmitter includes a media access (MAC) layer, wherein the MAC layer further includes a queue for storing data at each priority, a rate control block connected to each queue, and a physical (PHY) layer. The PHY layer further includes a channel coder for each priority, wherein each channel coder is connected to the corresponding queue to receive data, and to the rate control block to send coding information.

Abstract: A wireless network master node periodically broadcasts beacons that specify a structure of a following fixed length superframe. Slave nodes determine a channel condition between each slave and the master. Then, the set of slaves is partitioned into subsets of slaves according to the channel conditions. The master assigns, to each slave, a transmission rate in a low to high order according to the channel conditions, and the slaves transmit data to the master in the low to high order between two consecutive beacons, wherein the subsets of slaves with a higher transmission rate also receive the data from the subsets of slaves with a lower transmission rate, and wherein a slave with a higher transmission rate includes a part of or all the data from a slave with a lower transmission rate.

Abstract: A wireless star network includes including a master node (master) and a set of N slave nodes (slaves), wherein the network uses orthogonal frequency division multiple access (OFDMA). The master partitions the set of slaves in a first subset A(i) and second subset B(j), wherein the first and second subsets are disjoint. Packets are transmitted by the first subset of slaves only while the master and second subset of slaves operate in receive mode, and packets are transmitted by the second subset of slaves only while the master and first of slaves operate in receive mode.

Abstract: A location of an object is determined by arranging a sequence of bits on a substrate. The sequence of bits includes subsequence of bits, and each subsequence of bits is unique for each location along the substrate. When the object is at a particular location along the substrate a sensor detects the subsequence of bits at the particular location, and a decoder associates the location of the subsequence at the particular location with the object. The substrate can be a leaky coaxial cable with slits or not, corresponding to the bits, or lane markings on a road.