115 results about "Receiver Bandwidth" patented technology

A method and apparatus for attenuating a transmit signal spectrum in a receiver bandwidth. The apparatus relates to an adaptive, digital, coherent, spectral canceller. The method comprises digitizing both a corrupted receiver signal and a reference transmit signal and then digitally implementing an adaptive coherent spectral canceller module to suppress a residue transmit spectral signal power within the receiver bandwidth.

A radio spectrum management system is provided. In an embodiment, the radio spectrum management system includes a radio spectrum gateway, a radio spectrum management server and a radio spectrum policy decision server. The radio spectrum gateway is coupled to a radio access network that receives bandwidth requests from subscriber devices and provides bandwidth allocation decisions to the radio access network. The radio spectrum management server receives bandwidth requests from the radio spectrum gateway and provides bandwidth allocation decisions to the radio spectrum gateway based on radio resources and bandwidth policy decisions. The radio spectrum policy management server provides bandwidth policy decisions to the radio spectrum server. The bandwidth policy decisions are generated based on consideration of subscriber and / or application service provider characteristics. Methods for allocation of radio spectrum for a subscriber within a wireless network when the subscriber requests an application are also provided.

A method is presented for throttling data transmissions within a data processing system. Information about a data transfer from a server to a client is received within the application layer of a server, which stores the information about the data transfer along with information about a number of recent data transfers from the server to the client to create a sliding window of historical information about data transfers. The data transfer from the application layer of the server is delayed within the application layer of the server for an amount of time that is approximately equal to a computed delay time value in response to a determination that an average data transfer rate over the number of recent data transfers from the server to the client may exceed a data transfer rate threshold parameter.

Method and apparatus to carry out wideband DOCSIS both upstream and downstream in a point-to-multipoint environment of an HFC system using port trunking concepts. For the downstream, each CMTS has a frame distributor which distributes frames to various transmitters transmitting on downstream channels to be used to transmit downstream data simultaneously to a CM using wideband DOCSIS. The frame distributor adds sequence numbers in some embodiments to guarantee proper order of frames can be restored at the CM, and schedules transmissions according to quality of service considerations to meet guaranteed and committed portions of constant bit rate and variable bit rate flows. The CMTS sends and Extended Channel Enable (ECE) message to wideband capable CMs telling them which downstreams to enable. Each CM has a frame collector to which all frames received on various downstream channels are sent. The frame collector makes sure they are all there, puts them into the proper order and delivers them to a NI. Upstream wideband DOCSIS works the same way with a frame distributor in each CM and a frame collector in the CMTS. The CMTS receives bandwidth requests and controls upstream wideband DOCSIS transmissions by sending downstream UCD and MAP and ECE messages to the CMs instructing them which upstream channels to use, describing the parameters of the channel and assigning times for transmission which are simultaneous on multiple channels for upstream wideband capable CMs.

A system and method is provided for scheduling transmissions from a plurality of services operating over a widely distributed communications network. A headend communications device (such as a cable modem termination system) arbitrates bandwidth among a plurality of cable modems configurable for bi-directional communications. The headend grants a bandwidth region to a specified cable modem or assigns contention regions for a group of cable modems. Each cable modem contains a local scheduler that sends requests for bandwidth according to local policies or rules. Upon receipt of a grant from the headend, the local scheduler selects packets to be transmitted to best serve the needs of the services associated with the cable modem. Accordingly, a service requesting bandwidth may not be the service utilizing the grant corresponding to bandwidth request. Nonetheless, the local scheduler manages bandwidth allocation among its local services such that all requesting services eventually receive bandwidth.

A wireless base station device, connected to a higher-level station device via a wired line, comprises baseband processors 11, one for each virtual link 21 to which user data flows belong. In the baseband processor 11, a congestion monitor 51 monitors the reception bandwidth usage rate of a virtual link allocated to each cell for detecting congestion and, upon detecting congestion, sends a notification to a flow controller 57. A user traffic distributor 52 distributes a received user traffic into the traffic flow of each user and, at the same time, extracts, for each user data flow, the buffer holding amount in the higher-level station device where user data flows are multiplexed and sends a notification to the flow controller 57. The flow controller 57 manages the data flow of each user and, in response to a congestion notification from the congestion monitor 51, requests the higher-level station device to reduce the rate of a user data flow in descending order of rates beginning with a data flow with a highest rate.

The invention discloses a constant envelope multiplexing method of double-frequency four-component spread spectrum signals. The method comprises the following steps of: generating four signal components as corresponding baseband spread spectrum signals, and obtaining corresponding additional phase according to the value combination state of the baseband spread spectrum signals within the current period of time; generating a pair of components, of which the phases are orthogonal to each other, by the additional phase through a trigonometric function generator; generating two paths of carriers, which are orthogonal to each other, by a carrier generator, respectively multiplying the carriers by the generated components, and executing subtraction on the products to get a radio frequency signal meeting the constant envelope condition. The invention also provides a generation device of the constant envelope multiplexed signal, and a receiving method of the constant envelope multiplexed signal. According to the constant envelope multiplexing method, four signal components of two frequency points are synthesized into one constant envelope signal, so that low-range and medium-range receivers can process the signal with narrower receiving bandwidth and lower baseband so as to obtain the basic ranging performance, high-range receivers can get better ranging accuracy by wider receiving bandwidth and higher processing complexity, and the ranging performance of the receivers during receiving each signal component respectively is improved.

A system, program product, and method to determine water, fat, and transverse relaxation time constants in MRI scanning are provided. A method includes initiating readout gradient pulses to collect echo signals with identical phase encoded gradients to thereby produce a plurality of images, instead of a single image with a single readout gradient. A receiver bandwidth used for collecting the echo signals can be determined responsive to an acquisition matrix size along the readout axis and a time duration for water and fat signals to evolve by a preselected phase angle. In a modified FSE implementation, for example, a method includes using readout gradient pulses that use substantially all of the echo spacing time periods between successive refocus RF pulses. By exploiting the phase and the amplitude relationship between the images, the method can include processing the images to generate separate water and fat images, as well as quantitative maps of transverse relaxation time constants.

The invention provides a synchronizing cycle scheduling algorithm by accessing a wireless sensor network media to a control layer. The algorithm defines a characteristic frame structure and a time slot structure and has the characteristics of low node energy consumption, small transmission time lapse, easy realization, etc. The algorithm has the advantages that: 1) a time slot division method is adopted to avoid sending conflict between nodes and reduce the waiting time for receiving, thereby saving the node energy and having no strict need to node synchronization and easy realization. 2) The algorithm defines the characteristic frame structure and the processing flow in order that each node in a movable time slot (main time slot) has a scheduling function and can send data and receive data and information which is randomly accessed. 3) The node can freely adjust a sending and a receiving bandwidths with each adjacent node in the main time slot according to the needs. 4) Through setting a sending and a receiving cycles in a time slot, one node can acquire a plurality of chances to send the data in every frame cycle, thereby greatly reducing the network time lapse.

Method and apparatus to dynamically configure the signal reception selectivity of a plurality of transceivers is described. In one embodiment, a transceiver includes a receiver circuit having two or more filter circuits. Each of the filter circuits is configured to pass RF signals from a different portion of an overall receiver bandwidth. When two or more receivers in proximity to one another are simultaneously operating, the filter circuits of the respective receiver are dynamically configured to different RF frequency passbands to minimize interference and cross talk between receivers and transmitters.

A system and method of estimating radio frequency (RF) background noise in a radio receiver system comprises determining a total receiver front-end noise based on a noise equivalent receiver bandwidth; estimating external noise associated with the radio receiver system; determining internal noise associated with the radio receiver system from a known noise value; combining the external noise with the internal noise; determining an absolute external (RF) background noise floor associated with the radio receiver system; estimating an out of band noise contribution based on radio receiver selectivity and known received noise levels of out of band sources; and generating a (RF) noise estimate in the radio receiver system based on the above steps. The invention utilizes the (RF) noise estimate to form a (RF) receiver signal to noise ratio enabling an estimate performance of (RF) radio links in the radio receiver system operating in a benign and hostile (RF) environment.

A system, program product, and method to determine water, fat, and transverse relaxation time constants in MRI scanning are provided. A method includes initiating readout gradient pulses to collect echo signals with identical phase encoded gradients to thereby produce a plurality of images, instead of a single image with a single readout gradient. A receiver bandwidth used for collecting the echo signals can be determined responsive to an acquisition matrix size along the readout axis and a time duration for water and fat signals to evolve by a preselected phase angle. In a modified FSE implementation, for example, a method includes using readout gradient pulses that use substantially all of the echo spacing time periods between successive refocus RF pulses. By exploiting the phase and the amplitude relationship between the images, the method can include processing the images to generate separate water and fat images, as well as quantitative maps of transverse relaxation time constants.

A method and apparatus are provided for controlling connection to a communication path in a communication network. The apparatus receives a bandwidth request and determines a value of bandwidth expansion factor from information relating to transmission of data over the communication path, which may include the type of channel, the type of connection, the sizes of packet payload and the distribution of the size of packet payload for transmission on the communication path. The actual bandwidth being requested is determined using the bandwidth expansion factor and this information is used by a connection admission controller to allow or deny the requested connection, and / or by a scheduler to control data transmission.

A method for inroute bandwidth allocation supporting multiple traffic priorities in a satellite network including generating a backlog report, transmitting the backlog report to an inroute group manager, receiving a bandwidth allocation from the inroute group manager, and servicing priority queues and transmitting data to a satellite based on the bandwidth allocation from the inroute group manager.

The invention discloses a method and a device for prolonging the transmission distance of a passive optical network. The method comprises the steps that the sampling band width of an analog-digital converter at a receiving end is more than the symbol rate of a transmitted signal, corresponding spectrum aliasing is generated when the output signal of the analog-digital converter is sampled, and the frequency ingredient outside a transmitting signal frequency range in the sampled signal of the analog-digital converter is used for compensating the frequency ingredient of a power attenuation part after the optical fiber dispersion, so as to realize the compensation on the optical fiber transmission dispersion in the passive optical network. According to the method, the receiving bandwidth can be increased, the compensation on the optical fiber transmission dispersion in the passive optical network can be conveniently and effectively realized, and the method has the characteristics of being simple to realize, low in cost, significant in compensation effect, and is capable of greatly improving the signal quality of the receiving end.