Abstract: A universal mobile telecommunications system (UMTS) receiver uses Pilot Symbol Assisted Modulation (PSAM) in demodulating a received Binary Phase Shift Keying (BPSK) signal. The UMTS receiver uses a ratio of the transmitted energy per pilot symbol to the transmitted energy per data symbol as an index into a look-up table to return a value for a scale factor for use in demodulation of the received signal, which provides better performance during periods when the fading distribution is unknown.

Abstract: Hybrid fiber/coax networks employ the existing cable plant used for cable TV and transmit data signals in a frequency bandwidth above that which is used for cable TV. As this cable plant was deployed in a tree and branch topology, data transmissions may be susceptible to noise, variable transmission loss and frequency dispersion, particularly in the upstream direction. Further, due to the tree and branch topology, homes at the far end of the network experience much greater loss than do the homes that are near to the headend/ONU. The present system, which uses point-to-point data links between intelligent network elements located in the feeder/distribution network to provide reliable, secure, bi-directional broadband access. Digital signals, or messages, are terminated at the intelligent network elements, switched and regenerated for transmission across additional upstream or downstream data links as needed to connect a home to a headend or router.

Abstract: An addressing scheme for a packet-based multiaccess mobile communications system, which includes a plurality of mobile user stations and a plurality of network nodes, is provided. In such addressing scheme, each mobile station is assigned an address which is a combination (preferably, a concatenation) of a unique identifier of a network node with which the mobile station is currently associated and an identifier of the mobile station. The network node identifiers may be uniquely assigned by a network administrator, while the identifiers of the mobile stations may, for example, be set to a universal MAC address assigned to the station. The address may also include a port identifier which indicates the particular application flow associated with the accompanying packets. Similarly, each network node is assigned an address which is a combination (preferably, a concatenation) of its network node identifier and, preferably, an interface identifier. The address may also include a port identifier.

Abstract: The location of a mobile wireless communication unit in the service area of a CDMA communications system is predicted utilizing two likelihood functions that define maximum likelihood estimators of the mobile unit's location, based on attribute measurements, such as but not limited to pilot signal strength, being made at the location of the mobile unit and reported back to a base station. One of the likelihood functions comprises a frequentist likelihood function and the other comprises a Bayesian-modified likelihood function. The likelihood functions are based on the assumption that there is an RF model which provides the probability a mobile unit is able to detect one or more attributes associated with an arbitrary base station, given it is located at an arbitrary location within the service area. Each of the likelihoods are also incorporated into a sequential Bayesian procedure which outputs a posterior distribution indicative of the location of the mobile unit.

Abstract: In an ad-hoc mobile network, a geometry-based routing algorithm (GRA) is used to route traffic from a source node to a destination node. In the GRA, a source node maintains location information and routing information for all nodes in a local area and approximate location information for at least some nodes outside the local area. If the source node has to send a packet to a destination node outside their local area, then the source node uses the approximate location information of the destination node to identify which node in its local area is closer to the destination node than the source node. The source node then sends the packet to the identified local node for further routing.

Abstract: In an IP addressing aspect of the invention, a method for use in facilitating transfer of packets in an Internet Protocol (IP) based communications system, wherein the communications system includes a plurality of network nodes and a plurality of mobile user stations, comprises the steps of: (i) inserting an address option field in a packet header of a packet to be transferred in the communications system, the address option field including supplemental address related data for facilitating transfer of packets in the communications system; and processing the packet within at least one of a network node and a mobile user station in the communications system in accordance with the supplemental address related data in the address option field of the packet header. The address option field may comprise an address type field, an address length field and an address data field.

Abstract: Various methodologies and related apparatus associated with mobility management issues within a packet-based multiaccess mobile communications system, which includes a plurality of mobile user stations and a plurality of network nodes, are provided. Location management techniques include tracking and/or locating mobile stations within the system. The invention makes use of home and visiting location registers in which information such as mobile station addresses and/or host names associated with mobile stations are stored. Mobile access methodologies include a complete mobile access method and a direct mobile access method. The former allows a mobile station to preferably include a unique address in the packets being transmitted, while the latter allows the station to merely use the host name of the destination station. The invention also includes various in-call mobility management techniques, including handoffs, which make use of the concept of an anchor.

Abstract: In a mobility management aspect of the invention, several unique mobility management control messages are defined for use in performing various mobility management functions in the communications system with respect to the mobile user stations and network nodes. These messages may comprise: (i) a Location Update Message (LUM); (ii) a Location Confirm Message (LCM); (iii) a Location Query Message (LQM); (vi) a Location Reply Message (LRM); (v) a Registration Message (RM); and (vi) a Registration Reply Message. One or more of these messages are used in the IP-based system to perform mobility management functions such as location management, mobile access and in-call mobility management.

Abstract: In an IP addressing aspect of the invention, a method for use in an Internet Protocol (IP) based communications system, comprises the steps of: (i) assigning a temporary location IP address (e.g., LIPA) to a mobile user station in the communications system, the address being a combination of an identifier of the mobile user station (e.g., MID) and an identifier of a network node in the communications system with which the mobile user station is currently associated (e.g., RID); and transferring packets to and from the mobile user station in accordance with the temporary location IP address. The method may further comprise the step of changing the temporary location IP address assigned to the mobile user station when the station becomes associated with another network node of the communications system, the changed address being a combination of the identifier of the mobile user station and an identifier of the new network node.

Abstract: Hybrid fiber/coax networks employ the existing cable plant used for cable TV and transmit data signals in a frequency bandwidth above that which is used for cable TV. As this cable plant was deployed in a tree and branch topology, data transmissions may be susceptible to noise, variable transmission loss and frequency dispersion, particularly in the upstream direction. Further, due to the tree and branch topology, homes at the far end of the network experience much greater loss than do the homes that are near to the headend/ONU. The present system, which uses point-to-point data links between intelligent network elements located in the feeder/distribution network to provide reliable, secure, bi-directional broadband access. Digital signals are terminated at the intelligent network elements, switched and regenerated for transmission across additional upstream or downstream data links as needed to connect a home to a headend or router.

Abstract: A new protocol layer is provided as part of a protocol stack associated with a packet-based multiaccess mobile communications system. The protocol layer is preferably located above a medium access control (MAC) protocol layer and a physical protocol layer of the system and below a transport/network protocol layer. Such a subnetwork protocol layer provides, inter alia, the communications system with various mobility management functions, for example, tracking mobile user stations throughout the system, mobile station access to the system, and connection/call continuity within the system. The subnetwork protocol layer of the invention also performs packet routing functions associated with the system. Routing can be accomplished in many ways, for example, via source routing, connectionless routing, or tunneling. Further, the new protocol layer of the invention is preferably located above a data link layer with respect to the protocol stack associated with communications between network nodes.

Abstract: In a UMTS (universal mobile telecommunications system) based system, a wireless receiver implements “effective signal-to-noise (Eb/No) based BER estimation.” In particular, the wireless receiver comprises a rake receiver, a processor and memory. The rake receiver processes a received signal and provides signal-to-noise ratio values for each slot of each received frame of the received signal. The processor converts these signal-to-noise ratio values for each received frame into an effective signal-to-noise ratio value for the received signal. The processor then uses the effective signal-to-noise ratio value as a pointer, or index, into a look-up table (stored in the memory) and retrieves a BER estimate therefrom.

Abstract: A method and apparatus to quickly adjust a targeted Eb/N0 in a wireless communication system by using an effective Eb/N0 for each frame. The Eb/N0 distribution of a frame produces a certain frame error rate. Effective Eb/N0 is the Eb/N0 that would produce the same frame error rate in a model channel, such as an additive white Gaussian noise (AWGN) channel. The effective Eb/N0 for each frame is obtained and compared to a model targeted Eb/N0. The Eb/N0 for all of the power control groups in one frame compose the vector Eb/N0. The effective Eb/N0 for the frame is obtained by mapping a vector Eb/N0 into a scalar. The model targeted Eb/N0 is the Eb/N0 value that produces a desired frame error rate in the model channel. The targeted Eb/N0 is increased by one up step size when the effective Eb/N0 is smaller than the model targeted Eb/N0 and is decreased by one down step size when the effective Eb/N0 is larger than the model targeted Eb/N0. Eb/N0 are measured for each power control group in a frame.

Abstract: The location of a mobile unit in the service area of a CDMA cellular telephone system is predicted from a spatial probability distribution that is generated over a region of sub-cells within the service area. The spatial distribution, and hence the predicted location, is updated sequentially based on RF measurements provided by the mobile unit through the use of a Bayesian-update method.

Abstract: A mobile communications system employs extended channel assignment messaging during the call setup portion of a mobile call. As part of the call setup process, a mobile station sends an access request message to a primary base station that includes a list of alternate base stations. As call setup continues, the mobile station employs diversity reception in monitoring the paging channel of three base stations, each selected as a function of the strength of the signal-to-noise ratios of their respective pilot tones.

Abstract: The method of estimating a signal-to-noise ratio (SINR) estimates either the polarities or bit values of a plurality of received data symbol samples. Then an SINR estimate is generated based on the plurality of received data symbol samples and the estimated polarities or bit values of the plurality of received data symbol samples such that the SINR estimate is not substantially dependent on a polarities or a bit value of the plurality of received data symbol samples.

Abstract: In a UMTS (universal mobile telecommunications system) based system, a wireless receiver comprises a convolutional decoder, a processor and memory. The convolutional decoder processes a received signal and provides a Yamamoto-Itoh (YI) metric to the processor. The processor (a) retrieves, from a look-up table stored in the memory, a compensation factor as a function of the YI metric value provided by the Viterbi decoder; (b) retrieves, from another look-up table stored in the memory, an initial BER estimate as a function of the YI metric; and (c) modifies the initial BER estimate with the retrieved compensation value to provide a BER estimate.

Abstract: Hybrid fiber/coax networks employ the existing cable plant used for cable TV and transmit data signals in a frequency bandwidth above that which is used for cable TV. As this cable plant was deployed in a tree and branch topology, data transmissions may be susceptible to noise, variable transmission loss and frequency dispersion, particularly in the upstream direction. Further, due to the tree and branch topology, homes at the far end of the network experience much greater loss than do the homes that are near to the headend/ONU. The present system, which uses point-to-point data links between intelligent network elements located in the feeder/distribution network to provide reliable, secure, bi-directional broadband access. Digital signals, or messages, are terminated at the intelligent network elements, switched and regenerated for transmission across additional upstream or downstream data links as needed to connect a home to a headend or router.

Abstract: Hybrid fiber/coax networks employ the existing cable plant used for cable TV and transmit data signals in a frequency bandwidth above that which is used for cable TV. As this cable plant was deployed in a tree and branch topology, data transmissions may be susceptible to noise, variable transmission loss and frequency dispersion, particularly in the upstream direction. Further, due to the tree and branch topology, homes at the far end of the network experience much greater loss than do the homes that are near to the headend/ONU. The present system, which uses point-to-point data links between intelligent network elements located in the feeder/distribution network to provide reliable, secure, bi-directional broadband access. Digital signals, or messages, are terminated at the intelligent network elements, switched and regenerated for transmission across additional upstream or downstream data links as needed to connect a home to a headend or router.

Abstract: In a cellular system based on industry standard IS-95 CDMA (code division multiple access), a symbol error count based reverse link outer loop power control technique uses adaptive SER targets. In particular, a base station uses a 2nd order statistic, e.g., standard deviation (variance), to identify, or act as a signature of, a particular cellular (wireless) communications environment. The base station monitors the standard deviation of the symbol error count of a received signal (transmitted from a mobile station). The target signal-to-noise ratio (EbT/N0T) of this received signal is adjusted as a function of the value of the standard deviation and the adjusted EbT/N0T target is used to provide power control.