Abstract: Improved timing synchronization and access control techniques for use in an orthogonal frequency division multiplexed (OFDM) wireless system or other type of wireless communication system. In accordance with the invention, an uplink synchronization and access control system is provided in which mobile stations transmit certain timing and access signals in dedicated intervals in an uplink stream. Access control is illustratively implemented as a two-stage process in which a given mobile first transmits a generic uplink access signal in one of the intervals. If this access is accepted, the base station transmits an access acknowledgment containing initial timing and power corrections, along with initial channel assignments on which the mobile can initiate a call set-up process. For re-synchronization, mobiles transmit timing synchronization signals in the dedicated timing and access intervals. The base station measures the arrival time of the signals, and sends back appropriate timing corrections.

Abstract: A system and method for preventing a call from being dropped changes from a first set of serving base station(s) for the call to a second set of serving base station(s) which can be determined independently by both the wireless unit and the wireless communications system. As such, the wireless unit can attempt to recover the call using the second set of serving base station(s) even without the availability of a communication link between the wireless unit and the current set of serving base station(s). The wireless communications system can independently determine a second set of serving base station(s) for the call using information known at both the wireless communication system and at the wireless unit before the communication link was severed.

Abstract: The present invention provides a method for adhering dielectric layers to metals, in particular inert metals, using an adhesive layer comprising silicon-rich silicon nitride. Good adhesion is achieved at temperatures of less than 300° C., thereby facilitating the fabrication of semiconductor structures containing II-VI and III-V semiconductors.

Abstract: A tunable microlens uses at least two layers of electrodes and a droplet of conducting liquid. Such a droplet, which forms the optics of the microlens, moves toward an electrode with a higher voltage relative to other electrodes in the microlens. When calibration of the microlens is desired, an equal and constant voltage is passed over the first layer of electrodes and a different, constant voltage is passed over the second layer of electrodes, which may, for example, be disposed in a star-like pattern. A driving force relative to each electrode in the second layer results and is proportional to the length of the circumference of the droplet that intersects with each of the electrodes. This driving force reaches equilbrium, and hence the droplet reaches its nominal centered position relative to the second layer of electrodes, when the length of intersection of the circumference of the droplet with each of the electrodes in the second layer is equal.

Abstract: In a wireless communications system, a base station employs a bit error rate (BER) based Reverse Outer Loop Power Control (ROLPC) technique. The ROLPC technique uses either instantaneous or weakly filtered values of the BER for comparison with a BER target value for adjusting a target signal-to-noise ratio (SNR). The BER target value is varied as a function of a second order statistic (e.g. variance, standard deviation) of the received SNR. In another embodiment, a symbol error count based ROLPC 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).

Abstract: A method and apparatus for facilitating detection of satellite signals using a dynamic integration technique in which integration time periods of correlators are adjusted according to signal strength measurements of satellite signals received at GPS receivers. Specifically, integration time periods are inversely adjusted, either proportionally or non-proportionally, to received strengths of signals being searched.

Abstract: In a class of minimum cost flow control (MCFC) algorithms for adjusting session rates or window sizes congestion control is achieved through consideration of an incremental cost function that addresses link congestion, and an incremental cost function that addresses the cost of providing less than the desired transmission rate. A coarse version of the algorithm is geared towards implementation in the current Internet, relying on the end-to-end packet loss observations as indication of congestion. A more complete version anticipates an Internet where sessions can solicit explicit congestion information through a concise probing mechanism.

Abstract: A method of retrieving and manipulating electronic information that relates to a printed document. Each printed document contains an initialization marking that is recognizable by an external sensory device and unique to the printed document. When a reader of the printed document desires to retrieve and manipulate electronic information that relates to the printed document, the reader initializes the system by using the sensory device to recognize the initialization marking. The sensory device transfers a code embedded in the initialization marking to a computing device. This configures the computing device to access the stored data and instruction sets associated with the printed document. In addition to the initialization marking, areas throughout the printed document (e.g., text, tables, figures, etc.) also contain markings that are recognizable by the external sensory device.

Abstract: An application initiates a parent process (102) to begin executing the application. The parent process (102) creates a child process (104) to execute the application. The parent monitors the death of the child process using inter-process communications (118). The child process monitors the parent process using polling (114, 116). If the parent process detects the death of the child, the parent process creates another child to continue the processing of the dead child. If the child process detects the death of the parent process (119), the child creates another child process (120) to execute the application it previously executed. The original child, now a parent, monitors the child process via inter-process communication (128).

Abstract: A code-division multiple access power control for paging channel power and initial traffic channel power dynamically determines optimum initial channel power in accordance with pilot signal strength of a pilot signal as received at a mobile station and current forward link loading of the desired sector. The optimum initial paging channel power and initial traffic channel power may be determined either at a base station or a mobile switching center of the mobile communication system. A paging signal or call is transmitted from the base station to the mobile station over a paging channel and a traffic channel at the optimum paging channel and initial traffic channel power.

Abstract: A system for providing statistical multiplexing of speech, other real-time data services and non-real-time data services for point to point and point to multipoint communications. The system has fast access and assignment procedures that allow the multiplexing of real-time, delay-critical data services with non-real-time data services. Continuity of periodic control channels across speech talkspurt and silence periods for conversational voice is maintained to carry signal measurement reports, channel quality feedback, and “comfort” noise information between different parts of the system.

Abstract: Clients that are connected on a private network and which are assigned a private IP address that is not routable on the Internet can connect to the Internet through a router/server that includes a network address translator (NAT). For outgoing packets, the NAT translates the client's private source IP address and generalized port number (GPN) to the NAT's global IP address and GPN. For incoming packets sent to the NAT's global IP address and GPN, the NAT translates the global destination IP address and GPN to the client's private IP address and GPN. For protocols which cannot be directly supported by the NAT, such as those in the IPSec security protocol suite, the NAT is extended by creating in the NAT's translation table an entry that associates, for a specific unsupported protocol, a client's private IP address and GPN, the NAT's global IP address and GPN, and a foreign address on the Internet, that is valid until a specified or default expiration time.

Abstract: A method for transmitting data packets includes determining from the first header part of first data packets the original first destination address, storing the original first destination address of the first data packet in storing means, discarding the first header part, storing in storing means the first body part of the first data packet. Thereafter, a concatenated or second data packet is made that includes in the body part: a data part including the first body parts and a content information part including information about the number and position of the first body parts. Thereafter, the concatenated or second data packet is transmitted to the second destination address. Hereby an increase of the payload is achieved and therefore more effective use of network connections bandwidth. A method to receive a concatenated or second data packet, devices to perform these methods and a computer network including such devices are also described.

Abstract: A method and apparatus for determining a circuit path between a source node and a destination node within a network comprising a plurality of nodes by iteratively selecting appropriate next nodes using a shortest path algorithm and accepting or rejecting the selected next node based upon the bandwidth utilization level of the communications link to the next node. In the case of a lack of acceptable communication links or a determined circuit path exceeding an ideal circuit path by a predetermined amount, the threshold levels defining acceptable links are adjusted.

Abstract: A method and apparatus for communicating files over a communications network in which links, such as hyperlinks, to files are logical in nature, rather than physical in nature, i.e., associated with a particular electronic address. An up-to-date replication directory is maintained on each server and each server inserts current physical references corresponding to a file's logical references into a requested parent file, along with a reference to a server selection program, before the parent file is transmitted to the requesting client. The server selection program selects physical references in the order of their likelihood of providing the fastest response. If a queried server does not currently store the file, an alternate server is queried. Servers communicate with each other to create and delete replicas of files and to make corresponding updates to each server's replication directory.

Abstract: A method and apparatus for communicating between entities of a wireless cellular telecommunications system in protocols extended from the standard IS-41 Protocols. In accordance with the invention, different pairs of entities can communicate using different extended protocol dialects. The extended protocol dialects can include extra operations codes, extra parameter identifiers, or both. The extended protocol between each pair of entities of the system is assigned, but can be changed by an appropriate message. Advantageously, the basic spectrum for extended protocols can be enlarged by allowing different extended protocols between different entities and/or by switching extended protocol dialects between specific entities.

Abstract: The present invention provides apparatus and a method of fabricating the apparatus. The apparatus includes a substrate having a surface and an organic field-effect transistor (OFET) located adjacent the surface of the substrate. The OFET comprising a gate, a channel, a source electrode, and a drain electrode. The channel comprises a densified layer of organic molecules with conjugated multiple bonds, axes of the organic molecules being oriented substantially normal to the surface.

Abstract: The present invention incorporates methodologies developed in the Internet Engineering Task Force (IETF) Internet Protocol Security (IPSEC) Working Group into asynchronous transfer mode (ATM) and frame relay (FR) signaling to provide message integrity and origin authentication. In one implementation the invention provides a virtual private network (VPN) infrastructure with call control message integrity, origin verification, and transit network filtering. The invention utilizes a set of control plane messages based on the IPSEC authentication header (AH) methodology to provide these security mechanisms for ATM and FR network switching equipment and signaling protocols. This abstract itself is not intended to limit the scope of this patent. The scope of the present invention is pointed out in the appending claims.

Abstract: A time-division-multiplexed fixed wireless loop system and methods therefor are disclosed. The system comprises a plurality of cells each having a base station and a plurality of terminals. The base station includes a steerable and adjustable multibeam antenna for communicating with each of the terminals, which have fixed antennas. A cell controller associated with each base station allocates communication time slots so as to minimize mutual interference between base station/terminal links sharing the same time slot. Slot assignment is based on regional, periodically updated interference measurements that are stored in data bases.

Abstract: An OFDM receiver recovers an rf signal as in-phase (I) and quadrature phase (Q) components of a baseband signal sampled in an A/D converter. The I and Q components of a received symbol are correlated at all sampling points. Correlation values are averaged over the latest L frames and saved in an L-deep FIFO. Symbol amplitude and phase are computed and passed to an offset estimator and an OFDM frame synchronization estimator. A phase-locked loop oscillator provides a sample number identifying the OFDM frame boundary to the offset estimator. An estimated offset value is selected as the negative of the phase angle of the auto correlation.