54results about How to "Maximize data rate" patented technology

The present disclosure is a novel utility of a software defined radio (SDR) based Distributed Antenna System (DAS) that is field reconfigurable and support multi-modulation schemes (modulation-independent), multi-carriers, multi-frequency bands and multi-channels. The present disclosure enables a high degree of flexibility to manage, control, enhance, facilitate the usage and performance of a distributed wireless network such as flexible simulcast, automatic traffic load-balancing, network and radio resource optimization, network calibration, autonomous/assisted commissioning, carrier pooling, automatic frequency selection, frequency carrier placement, traffic monitoring, traffic tagging, pilot beacon, etc. As a result, the SDR DAS can increase the efficiency and traffic capacity of the operators' wireless network.

Provided is a routing method in a multi-hop relay cellular network including a mobile station (MS), a base station (BS), and at least one relay station (RS). One of RSs neighboring the MS measures quality of a link to the BS, generates link quality information using the measured link quality, and transmits the link quality information to the MS. The MS receives the link quality information from the RSs, selects an optimal path depending on the received link quality information, and transmits information on the selected optimal path to the BS.

A method and apparatus for the transmission of short data bursts in CDMA/HDR networks. Dormant access terminals are assigned to a common traffic channel and rate group by an access point. The access point then informs the access terminals of the assigned common traffic channels and rate groups. The access point then transmits short data bursts to the dormant access terminals using the assigned common traffic channels and rate groups. If an access terminal fails to acknowledge receipt of a short data burst, then the access terminal is re-assigned to a new common traffic channel and rate group and transmission of the short data bursts is re-attempted. If an access terminal fails to acknowledge receipt of a short data burst more than a predetermined number of times, then the access terminal is placed in an active mode of operation. The transmission of short data bursts may be further assigned to time slots within the common traffic channels and rate groups in order to conserve the resources of the access terminals.

Systems and methods that provide channel bonding in multiple antenna communication systems are provided. In one embodiment, a method for signal transmission over a plurality of antennas of a transmitter may include, for example, one or more of the following: demultiplexing an input signal into a plurality of signal components; assigning each of the signal components to one of a plurality of logical channels; weighting each of the signal components with transmit baseband weight values; combining ones of the resultant weighted signal components to form a plurality of transmit weighted signals, each of the plurality of transmit weighted signals being assigned to one of the plurality of logical channels; and combining groups of the plurality of transmit weighted signals to form a plurality of output signals capable of being used to generate a plurality RF output signals.

The present invention relates to a data transmission/receiving method and apparatus for overcoming interference between multiple data streams, by relaying only part of multiple data streams that are received from a source node during collaborative data transmission employing relay nodes. The multiple data stream transmission method of the present invention comprises: receiving a plurality of data streams from a source node; decoding the plurality of data streams received; selecting a portion of the successful decoded data streams; encoding the selected portion of the data streams; and sending the encoded data stream portion to a destination node.

A communication method and device operates in a network in which a multiplicity of communication devices communicate over a shared communication channel. The communication device includes a transmitter that transmits to a second communication device over the shared communication channel a first packet P1, employing a starting tone map TMS that includes a starting transmission scheme for a set of carriers of said channel, a receiver that receives over the shared channel a partial tone map PTM1 from the second communication device, and a tone map generator that generates an updated tone map TM1 based on the starting tone map TMS modified in accordance with the partial tone map PTM1. The transmitter transmits over the shared channel a second packet P2 to the second communication device, employing the updated tone map TM1. The partial tone map may be received as part of an acknowledgment packet from the second communication device.

A method that includes interference control at transmitters and interference mitigation at receivers in a wireless communication system is disclosed. Embodiments of the present invention exploit the interference sensitivity at neighboring terminals by taking into account the reciprocity of propagation radio channels in Time Division Duplexing systems (TDD). It can be applied to design the resource allocation for downlink (DL) and uplink (UL) transmissions in a wireless communication system. The methods include the self-configuration of the transmit power, the transmit precoder and the receive filter, at each transmitter and receiver in a multi-cell network. Systems are also provided and configured for implementing the methods of the invention.

The invention discloses a DCO-OFDM (Direct-Current-Biased Orthogonal Frequency Division Multiplexing) DC bias and rapid power optimizing method under double restrictions aiming at visible light communication. DCO-OFDM DC bias and subcarrier power optimizing is a complex non-convex and non-linear optimizing problem. The DCO-OFDM DC bias and rapid power optimizing method can quickly seek the optimum DC bias Bdc and subcarrier power pk distribution scheme on the conditions of optical power limitation or electric power limitation or both optical power limitation and electric power limitation. The DC bias Bdc and subcarrier power pk obtained through the DCO-OFDM DC bias and rapid power optimizing method can maximize the data rate of the system or minimize the bit error rate in the fixed modulation scheme. The DCO-OFDM DC bias and rapid power optimizing method has the advantages of fast rate of convergence, small calculation amount, easiness in achievement, high result accuracy, etc.

The drone comprises M antennas, with in particular two offset antennas located symmetrically at the ends of two arms for the connection to the propulsion units (24), and a ventral antenna under the drone body. The radio transmission is operated simultaneously on N similar RF channels, with 2≤N<M. An antenna switching circuit couples selectively each of the N RF channels to N antennas out of the M antennas according to a plurality of different coupling schemes, dynamically through a piloting logic selecting one of the coupling schemes. The selection is operated as a function of a signal delivered by the drone-borne microprocessor, as a function of the flight and signal transmission conditions, determined at a given instant.

A first transceiver (200) sends (102) a predetermined number of blocks of data to a second transceiver, and records (104) on which of a plurality of sub-carriers each of the blocks of data is sent. The first transceiver receives (106) from the second transceiver a list of the blocks of data that were received with errors, and calculates (108) from the list a plurality of error rates corresponding to the plurality of sub-carriers. The first transceiver then determines (110) the SQE for each of the plurality of sub-carriers from the plurality of error rates, and adjusts (112) the data rate in accordance with the SQE determined for each of the plurality of sub-carriers. These processes can be implemented as a method that is facilitated by a software program.

The invention discloses a direct current bias and sub-carrier power joint optimization method of a visible light communication DCO-OFMD system under a non-flat channel. The object of the optimal design is to maximize system data rate by adjusting the direct current bias and the sub-carrier power under certain luminous power limitation or electric power limitation. The method comprises the steps as follows: (1) initializing relative parameters such as a channel parameter, a limitation condition, an initial sub-carrier power distribution, and so on; (2) fixing the sub-carrier power distribution, and optimizing direct current bias size and effective power; (3) fixing the direct current bias size and the effective power, and optimizing the sub-carrier power; (4) repeatedly executing the steps (2) and (3) until there is a convergence, and outputting the final direct current bias size and the sub-carrier power. The method of the invention could accurately obtain the optimal direct current bias size and a sub-carrier power distribution solution under a plurality of conditions such as luminous power limitation, electric power limitation, and so on, and the optimization method is fast in rate of convergence, easy to realize and high in result precision.

A transmitter comprising a programmable optical vector modulator and method for coherent optical signal communication. The transmitter includes a transmitter laser whose output is coupled by way of an optical fiber to an amplitude modulator. The output of the amplitude modulator is coupled by way of a length of optical fiber to a phase modulator. The phase modulator generates a modulated light output from the transmitter. Amplitude modulation is achieved by inputting data and a data clock signal to amplitude symbol mapping logic whose outputs are selectively weighted, summed, amplified and input to the amplitude modulator to amplitude modulate the output of the transmitter laser. Phase modulation is achieved by inputting the modulating data and the data clock signal to phase angle symbol mapping logic whose outputs are selectively weighted, summed, amplified, delayed to synchronize with the arrival of the light from the amplitude modulator, and input to the phase modulator to phase modulate the amplitude modulated output of the transmitter laser. The programmability of the vector modulator allows the transmission of an M-ary modulation format that maximizes the data transmission for a given optical dynamic range and bit error rate target. Also, the programmability allows for rapid change in modulation format to maximize data transmission for changes in optical dynamic range and bit error rate target. The M-ary constellation may be predistorted to compensate for equipment piece part variation and fiber nonlinear effects; in particular the effect commonly known as “self-phase modulation”.

In a method and system for operating an ADSL access network which has a plurality of data connections (19) between the access network and end user devices (10), and in which the access network controls the rate at which data is transferred between the user devices and an onward connection (50), the access network stores a plurality of capped profiles each of which specifies a respective upper data rate to which the connection is limited and which is below the maximum achievable rate for the connection. The access network operates using a Dynamic Line Management (DLM) algorithm which, for a given data connection, operates to enable data transfer at a variable data rate up to the maximum rate, monitors the error performance and signal to noise margin variation for different data rates and, in the event that one or both are outside respective limits for a predetermined period, selects and applies one of the capped profiles to limit the upper data rate, selection being determined by the highest data rate achieved for which the error performance was within acceptable limits.

Practical methods and apparatuses are provided for determining network clusters in wireless backhaul networks comprising a plurality of hubs and Remote Backhaul Modules (RBM) (104) based on link quality value (LQV) metrics. From an input LQV table of LQV values for each hub-RBM link (110), the link quality values are first ranked. Clusters are then identified from all the possible links based on the order of the highest link quality value to the lowest link quality value, any constraints on the number of RBMs per cluster, and clustering each RBM only once. Links with strong link quality values are chosen to optimize the LQV metric. LQV based clustering achieves a higher average LQV, e.g., average spectrum efficiency or weighted sum spectrum efficiency, for the entire backhaul network compared to the geographic location based clustering. The method is straightforward to implement and has low computational complexity.

The invention discloses an antenna selection and resource allocation method in a wireless energy supply communication network. The wireless energy supply communication network constructed by the method is a multi-user network architecture based on an orthogonal frequency division multiplexing technology, and comprises a hybrid access point; the hybrid access point is connected with K users downwards; and each user has two antennas for transceiving radio frequency signals. The method is based on an energy self-recovery technology; by combining antenna selection and resource optimal allocation,under the energy causality constraint, a total data rate of the users is maximized, resource allocation efficiency in the wireless power supply communication network is promoted, and the total data rate of all the users is maximized.

A method and apparatus for adaptively allocating resources by a Base Station (BS) apparatus in a multi-user OFDM system is provided. The method includes receiving users' required rates and channel state information from a plurality of user terminals, setting a required inter-user transmission ratio and a number of multi-frames based on information about the users' required rates, allocating a subcarrier and transmit power to each user terminal based on the channel state information and the required inter-user transmission ratio for a period corresponding to the set number of multi-frames, and redistributing the transmit power allocated to the subcarrier. The method and apparatus can maximize the total data rate of a system while satisfying required inter-user transmission ratios in a multi-user OFDM system based on a multi-frame environment.

A system and method for generating weight values based on maximum data rate for weighting elements included within signal weighting and combining arrangements used in various multi-antenna transmitter and receiver structures is disclosed herein. Weighting values for a given signal combining arrangement are set so as to maximize an output data rate of the applicable multi-antenna system in the presence of adaptive bit loading of the subcarriers of a transmitted signal. The disclosed techniques may be employed to maximize a data rate of a multi-antenna communication system by using adaptive bitloading and RF and baseband weighting schemes. In this case a search is conducted over various combinations of RF and baseband weights in order to find the weight combination which, when adaptive bitloading is also employed, maximizes the data rate.

High data rate inter-satellite communications links method for a plurality of satellites comprising providing, for each satellite, an ultrafast time hopping wireless satellite communications link of an allowed bandwidth in which data is transmitted using individual packets or pulses in a sequence of such packets or pulses, causing the individual packets or pulses to be short in duration so that the individual packets are pulsed and signal energy is spread over the allowed bandwidth substantially simultaneously and instantaneously. A time hopping sequential code is used to position the packets or pulses precisely in sequence thereby providing optimum use of frequency space and also providing noninterfering transmission channels due to the orthogonality of the coding scheme used.

A communication method is provided, which is implemented by a base station of an access network in order to allocate spectrum resources among terminals identified by the station, the station having already allocated all of its spectrum resources to identified terminals having communication set up via the base station. These terminals determine a group of terminals. The method includes: verifying admissibility of a pair of terminals that are candidates for direct communication by determining a set of served terminals that are candidates for sharing their respective spectrum resources with the pair under the sole constraint of the candidate terminal and the pair satisfying their respective QoS criteria.

A method for high rate data delivery in a multi-hop vehicular network comprises at each source vehicle, initiating a packet having a flow tag, assigning an identifier of the content and the current location to the flow tag, and forwarding the packet; at each destination vehicle, setting a flow request and broadcasting at the current intersection; further on movement, setting the flow request at the new intersection, and at each intersection, selecting a header vehicle at the intersection, computing backlog and congestion indicators and listening for broadcasts with a matrix and the flow requests at the header vehicle, determining if the matrix is present, updating the matrix in accordance with the backlog and congestion indicators if the matrix is present, initializing the matrix and estimating the delay on the outgoing road segments if the matrix is not present, forwarding the packet flow, and broadcasting the matrix from the header vehicle.