7839results about "Transmission path multiple use" patented technology

Carrier Interferometry (CI) provides wideband transmission protocols with frequency-band selectivity to improve interference rejection, reduce multipath fading, and enable operation across non-continuous frequency bands. Direct-sequence protocols, such as DS-CDMA, are provided with CI to greatly improve performance and reduce transceiver complexity. CI introduces families of orthogonal polyphase codes that can be used for channel coding, spreading, and / or multiple access. Unlike conventional DS-CDMA, CI coding is not necessary for energy spreading because a set of CI carriers has an inherently wide aggregate bandwidth. Instead, CI codes are used for channelization, energy smoothing in the frequency domain, and interference suppression. CI-based ultra-wideband protocols are implemented via frequency-domain processing to reduce synchronization problems, transceiver complexity, and poor multipath performance of conventional ultra-wideband systems. CI allows wideband protocols to be implemented with space-frequency processing and other array-processing techniques to provide either or both diversity combining and sub-space processing. CI also enables spatial processing without antenna arrays. Even the bandwidth efficiency of multicarrier protocols is greatly enhanced with CI. CI-based wavelets avoid time and frequency resolution trade-offs associated with conventional wavelet processing. CI-based Fourier transforms eliminate all multiplications, which greatly simplifies multi-frequency processing. The quantum-wave principles of CI improve all types of baseband and radio processing.

Carrier Interferometry (CI) provides wideband transmission protocols with frequency-band selectivity to improve interference rejection, reduce multipath fading, and enable operation across non-continuous frequency bands. Direct-sequence protocols, such as DS-CDMA, are provided with CI to greatly improve performance and reduce transceiver complexity. CI introduces families of orthogonal polyphase codes that can be used for channel coding, spreading, and / or multiple access. Unlike conventional DS-CDMA, CI coding is not necessary for energy spreading because a set of CI carriers has an inherently wide aggregate bandwidth. Instead, CI codes are used for channelization, energy smoothing in the frequency domain, and interference suppression. CI-based ultra-wideband protocols are implemented via frequency-domain processing to reduce synchronization problems, transceiver complexity, and poor multipath performance of conventional ultra-wideband systems. CI allows wideband protocols to be implemented with space-frequency processing and other array-processing techniques to provide either or both diversity combining and sub-space processing. CI also enables spatial processing without antenna arrays. Even the bandwidth efficiency of multicarrier protocols is greatly enhanced with CI. CI-based wavelets avoid time and frequency resolution trade-offs associated with conventional wavelet processing. CI-based Fourier transforms eliminate all multiplications, which greatly simplifies multi-frequency processing. The quantum-wave principles of CI improve all types of baseband and radio processing.

Device, system and method, in a vehicle communication system, to transmit wirelessly a message comprising the position, heading and speed of a vehicle or other moving object, wherein the transmission is repeated at regular intervals in a temporarily fixed time slot within a predetermined basic time interval. In a key embodiment the message duration is equal to or less than a predetermined time slot duration. Embodiments use generally the same time slot in a contiguous sequence of basic time intervals. Algorithms are described to resolve wireless interference within a time slot. Embodiments divide the basic time interval in multiple durations, “class regions,” for different message classes. Embodiments use different wireless bandwidth allocation algorithms for the class regions.

A system for remotely updating software on at least one electronic device connected to a network. The electronic devices have a non-volatile rewritable storage unit divided into at least two partitions, one of which will contain core firmware and the other of which will contain auxiliary software. When an update is received at the device, the updated core firmware is written to overwrite the partition in the rewritable storage unit that contained the auxiliary software. When this is completed and verified, the previous version of the core firmware stored in the storage unit is disabled from execution by the device. Next, the updated auxiliary software is written to overwrite the old version of the core firmware. When this write is complete, the device determines a suitable time for it to be rebooted to execute the updated software. In another embodiment, the present core firmware in the device is copied from the partition it is in to the other partition, overwriting the auxiliary software stored there. The new core firmware received to update the device is overwritten into the first partition, the old copied core firmware being present in case of an upgrade failure, and upon a successful update of the first partition, the auxiliary software is written to the second partition, overwriting the copied old core firmware. In this manner, the position of the core firmware and auxiliary software within the partitions is preserved during normal operation of the device.

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.

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

A system for acquiring, and displaying, data such as physiological data, from a plurality of data connection devices, each of which monitor one or more different parameters and output data at different sampling frequencies based on their own system clocks. The system receives the data signals at different sampling frequencies and associates each sample of each signal with a time stamp derived from a single master clock. Low rate and high rate data are treated differently. Low rate data is associated with the current value of the master clock, where as high rate data is time stamped by giving the first sample a time stamp equal to the current value of the current master clock, subsequent samples being given an estimated time stamp based on the expected interval between samples derived from the sampling frequency of the data collection device, and the timescale given to the first example. The estimated time stamp may be periodically corrected, and the estimation calculation can be improved by correcting the value used for the interval between samples. The different signals can be displayed together on a display aligned with respect to a time axis. The system can display, the data in two different timescales, one showing a few seconds of data and one showing a few hours of data. The data traces are scrolled across the time axis, new data being added to one end of the trace.

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 wireless communication system transmits data on multiple carriers simultaneously to provide frequency diversity. Carrier interference causes a narrow pulse in the time domain when the relative phases of the multiple carriers are zero. Selection of the frequency separation and phases of the carriers controls the timing of the pulses. Both time division of the pulses and frequency division of the carriers achieves multiple access. Carrier interferometry is a basis from which other communication protocols can be derived. Frequency hopping and frequency shifting of the carriers does not change the pulse envelope if the relative frequency separation and phases between the carriers are preserved. Direct sequence CDMA signals are generated in the time domain by a predetermined selection of carrier amplitudes. Each pulse can be sampled in different phase spaces at different times. This enables communication in phase spaces that are not detectable by conventional receivers. The time-dependent phase relationship of the carriers provides automatic scanning of a beam pattern transmitted by an antenna array. In waveguide communications, the carrier frequencies and phase space may be matched to the chromatic dispersion of an optical fiber to increase the capacity of the fiber.

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 and method for synchronizing a local clock to a reference clock using a linear model of the clock error between the local clock and the reference clock is disclosed. In one embodiment, a double-exponential smoothing process is used in conjunction with the linear model to estimate a frequency offset by which the frequency of an oscillator of the local clock is adjusted. Also disclosed herein is a phased-lock loop (PLL) adapted to synchronize a local clock with a reference clock using the double-exponential smoothing process, as well as a system implementing the PLL for timing the playout of data received from a transmitter.

A system and method for synchronizing a local clock to a reference clock using a linear model of the error between the local clock and the reference clock is disclosed. In one embodiment, a direct smoothing process is used in conjunction with the linear model to estimate a frequency offset by which the frequency of an oscillator of the local clock is adjusted. Also disclosed herein is a phased-lock loop (PLL) adapted to synchronize a local clock with a reference clock using the direct smoothing process, as well as a system implementing the PLL for timing the playout of data received from a transmitter.

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 technique for synchronizing clocks in a network is disclosed. In one exemplary embodiment, the technique may be realized as a method for synchronizing clocks in a network. The method comprises receiving a first timestamp and a second timestamp, each indicating a respective time instance as determined by a first clock signal within the network. The method also comprises measuring a first time interval between the first timestamp and the second timestamp. The method further comprises generating a difference signal representing a difference between the first time interval and a second time interval, and generating a second clock signal based upon the difference signal such that the second clock signal is synchronized with the first clock signal.

A method of modulating communications signals, such as optical fiber, wired electronic, or wireless signals in a manner that facilitates automatic correction for the signal distortion effects of echoes and frequency shifts, while still allowing high rates of data transmission. Data symbols intended for transmission are distributed into N×N matrices, and used to weigh or modulate a family of cyclically time shifted and cyclically frequency shifted waveforms. Although these waveforms may then be distorted during transmission, their basic cyclic time and frequency repeating structure facilitates use of improved receivers with deconvolution devices that can utilize the repeating patterns to correct for these distortions. The various waveforms may be sent in N time blocks at various time spacing and frequency spacing combinations in a manner that can allow interleaving of blocks from different transmitters. Applications to channel sounding / characterization, system optimization, and also radar are also discussed.

Systems and methods are disclosed for time synchronization of operations in a control system. Synchronization networks and devices are provided for transferring synchronization information between controllers in a distributed or localized control system, which is employed in order to allow operation of such controllers to be synchronized with respect to time. Also disclosed are synchronization protocols and hardware apparatus employed in synchronizing control operations in a control system.

Disclosed is a power line broadband communication system having broadband coupler devices capable of direct electrical connection to an energized power line. The coupler includes a conductive portion movable by an adjustable member from a non-conducting retracted position spaced apart from the power transmission line to a forward conducting position in electrical contact with the power line. An insulated arm supports the coupler on the power line. A base on the coupler is engageable with a remotely activated tool in order to accomplish the electrical connection in a safe and secure manner. Broadband data signals are sent to and from customer premises along the shared energized power lines. New coupler connections to the energized power lines allow the additional broadband customers and / or repeaters to join the communication system. Also couplers may provide connections to control electronics, routers, wireless transceivers, and may allow the broadband signals to bypass transformers on the power lines. The invention helps to minimize risk by allowing an installer to be remotely spaced from the energized power line while making the electrical coupling contact with the energized power line.

The present invention provides a method for realizing transmission of multiprotocol client signals in a distributed base station subsystem, comprising: encapsulating client signals by a GFP-T frame; and mapping said GFP-T frame into a lower-layer transmission link to realize the transmission of client signals. Said lower-layer transmission link is a common public radio interface CPRI link. Said client signals are one of the following: baseband I / Q signals of WCDMA supported by CPRI protocol, baseband I / Q signals of radio interface protocols other than WCDMA, structured signals of E1 / T1, STM-1 and other constant-rate links, structured variable-rate link signals such as Ethernet MAC frame signals, PPP / HDLC frame signals, etc. This method is also applicable to other types of synchronous transmission links between a remote radio unit and a primary baseband processing unit, e.g., the links as specified by OBSAI (Open Base Station Architecture Initiative).

Applications of CI processing to ad-hoc and peer-to-peer networking significantly improve throughput, network capacity, range, power efficiency, and spectral efficiency. CI-based subscriber units perform network-control functions to optimize network performance relative to channel conditions, network loads, and subscriber services. CI codes are used to identify and address network transmissions. Channel characteristics of communication links are employed to encode, address, and authenticate network transmissions. CI transceivers used as relays and routers employ unique characteristics of transmission paths to code and decode network transmissions. A central processor is adapted to perform array processing with signals received from, and transmitted by, a plurality of subscriber units in a wireless network.

Techniques for reducing peak-to-average power in multicarrier transmitters employ peak cancellation with subcarriers that are impaired by existing channel conditions. The use of Carrier Interferometry (CI) coding further improves the effectiveness of peak reduction. CI coding can also be impressed onto pulse sequences in the time domain, which enhances spectral selection and facilitates peak-power control.

Nodes in a network include a pseudo-timestamp in messages or packets, derived from local pseudo-time clocks. When a packet is received, a first time is determined representing when the packet was sent and a second time is determined representing when the packet was received. If the difference between the second time and the first time is greater than a predetermined amount, the packet is considered to be stale and is rejected, thereby deterring replay. Because each node maintains its own clock and time, to keep the clocks relatively synchronized, if a time associated with a timestamp of a received packet is later than a certain amount with respect to the time at the receiver, the receiver's clock is set ahead by an amount that expected to synchronize the receiver's and the sender's clocks. However, a receiver never sets its clock back, to deter attacks.

One or more methods and systems of effectively transmitting voice and voice band data from one node to another are presented. In one embodiment, the system comprises an NTP time server generating absolute times to computing devices such as residential voice over internet protocol (VoIP) gateways. The NTP time server generates absolute times in response to NTP time requests made by one or more computing devices such as residential VoIP gateways. In one embodiment, the method comprises determining an adequate rate for requesting absolute times from an NTP server, making periodic requests to the NTP server, obtaining the absolute times from the NTP server, and generating an adjustment parameter for use by a computing device such as a residential VoIP gateway.

An interval centroid-based watermark encoder encodes a watermark into a packet flow. Intervals are defined for the packet flow. Some of the intervals are selected as group A intervals while other intervals are selected as group B intervals. Group A and group B intervals are paired and assigned to watermark bits. A first or second value may be encoded by increasing the relative packet time between packets in either the group A (for the first bit value) or group B (for the second bit value) interval(s) of the interval pair(s) assigned to the watermark bits that are to represent the first or second bit value and the beginning of the same group interval(s). The relative packet times may be measured by a decoder and used to calculate a centroid difference for each interval pair. The centroid differences may be used to reconstruct the watermark.

In a wireless communication system, a base station assigns resources to mobile stations using indices. Each index is associated with an assignment schedule for assigning resources. Once the base station determines an assignment schedule to assign particular resources, it encodes the schedule into an index and transmits it. A mobile station receives the index and decodes it to recover the assignment schedule. Both the base station and the mobile station may use look-up tables and / or algorithms for storing or generating indices associated with assignment schedules. To assign resources so as to indicate transmission characteristics over the resources, the base station transmits assignment blocks. Each assignment block indicates original transmission, retransmission, persistent assignment, non-persistent assignment, HARQ signaling, RAS-HARQ signaling, DRCH assignment, and / or LRCH assignment.

A method and system for detecting viruses on handheld computers. The handheld computer is in communication with a computer system having a virus detection program. The method includes reading data from the handheld computer and writing the data at least temporarily to a database on the computer system. The data is scanned for viruses with the virus detection program. The method further includes updating data on the handheld computer based on results of the scanning.

Estimates of a communication system configuration, such as a DSL system, are based on operational data collected from a network element management system, protocol, users and / or the like. The operational data collected from the system can include performance-characterizing operational data that typically is available in an ADSL system via element-management-system protocols. Generated estimates and / or approximations can be used in evaluating system performance and directly or indirectly dictating / requiring changes or recommending improvements in operation by transmitters and / or other parts of the communication system. Data and / or other information may be collected using “internal” means or may be obtained from system elements and components via email and / or other “external” means. The likelihood of a model's accuracy can be based on various data, information and / or indicators of system performance, such as observed normal operational data, test data and / or prompted operational data that shows operating performance based on stimulation signals. One example of such prompted data uses frequency carrier masks to approximate the Hlog of a given channel, including information regarding bridged taps, attenuation, etc.

A system and method for synchronizing devices which can couple to the Internet, or any network. In one aspect a system for synchronizing data between a first system and a second system is provided. The system includes a first sync engine on the first system interfacing with data on the first system to provide difference information. A data store is coupled to network and in communication with the first and second systems. A second sync engine is provided on the second system coupled to receive the difference information from the data store via the network, and interfacing with data on the second system to update said data on the second system with said difference information. Difference information is transmitted to the data store by the first sync engine and received from the data store from the second sync engine. The system may include a management server coupled to the network and in communication with the first sync engine, the second sync engine and the data store. The system may include a plurality of sync engines on a respective plurality of systems, each of said plurality of engines being coupled to receive difference information from each of said first, second and plurality of sync engines from the data store via the network. Each said engine interfaces with data on the system on which it resides to update said data on said system on which it resides with said difference information, and interfaces with data on said system on which it resides to provide difference data information from the system on which it resides to the data store. In a further embodiment, the invention comprises a method for synchronizing at least a first file and a second file resident on a first and a second systems, respectively, coupled to the Internet, respectively. The method includes the steps of: determining difference data resulting from changes to the first file on the first system; transmitting the difference data to a server via the Internet; querying the server from a second system to determine whether difference data exists for files on the second system; retrieving the difference data to the second system; and updating the second file on the second system with the difference data.

Sending channel related parameters known as channel state information (CSI) over a WLAN return channel. The size of these coefficients is not fixed. Rather, the coefficients are quantized in a certain resolution, which is determined adaptively according to a measure of the channel quality. This allows minimizing the component of the bandwidth of the wireless connection that is not used for payload transfer.

A redundently modulated multicarrier protocol known as Carrier Interference Multiple Access (CIMA) is used in an optical-fiber network having wireless links at network nodes. CIMA is a protocol that can be used to create wireless protocols (such as TDMA and CDMA) having enhanced capacity and reduced system complexity. A CIMA optical-fiber network uses dispersion to enhance signal quality and facilitate switching. CIMA achieves both diversity benefits and capacity enhancements by providing redundancy in at least one diversity parameter while providing orthogonality in another diversity parameter. This basic operating principle of CIMA may be combined with multi-user detection to achieve frequency reuse and improved power efficiency. In the wireless link, diversity may be used to reduce the effects of small-scale fading on interferometry multiplexing.