139 results about "Statistical time division multiplexing" patented technology

A system and method for managing the allocation of Time Division Multiplexing (TDM) timeslots in a network switch. The network switch may use a TDM cycle comprising multiple timeslots to manage shared resources and to schedule data ingress and egress through the ports of the current configuration, wherein each port is assigned one or more timeslots. The network switch may be reprogrammed to support one of multiple timeslot assignment schemes for one of multiple port configurations. The network switch may support configurations with varying numbers of ports, e.g. 8- and 16-port configurations. A network switch may also support configurations where two or more ports are combined to form one port, for example, a 2 Gbs Fibre Channel port. To meet the requirements of the various configurations, the timeslot assignment scheme may be reprogrammed to meet the scheduling requirements of each of the possible port configurations.

A method for subcarrier allocation and loading for a multi-carrier, multi-subscriber system is described. At least one cluster in a first and second set of clusters of subcarriers is associated for use in communication with a first and second subscriber, respectively. Then, for each cluster associated for use in communication with the first subscriber and the second subscriber, usage of that cluster is multiplexed between the first subscriber during a first time division and the second subscriber during a second time division.

A method and apparatus for spatial multiplexing and demultiplexing of radio signals. A multichannel transmitter and receiver is integrated in a base station and coupled to an antenna array. Using digital radio signals containing previously known or non-Gaussian sequences and arranged in frames, the spatial information about each mobile unit is estimated on the basis of the signal received by the receiver for the reception and transmission frequencies. This is done by known sequences or by blind source separation methods. The respective paths of each mobile unit with the power above a predetermined threshold is isolated by spatial filtering in the presence of multiple channel paths in order to provide spatial demultiplexing. Simultaneously, the intended signal is transmitted in the direction of the main path of each mobile unit while protecting each mobile unit from signals transmitted in the direction of other mobile units by spatial filtering with cancelling constraints in order to provide spatial multiplexing.

Methods and apparatuses to design and analyze digital circuits with time division multiplexing. At least one embodiment of the present invention efficiently models subsystems connected by a TDM channel by introducing equivalent delays in the connections for the subsystems, where the delays are determined according to the upper bounds of the delays caused by the TDM channel. The TDM channel is modeled with its equivalent delays. Thus, a transformation tool is allowed to take into account the original constraints and time budgeting of the sending subsystem and the receiving subsystem. The problem of asynchronous clock domains is eliminated; and, simulation time of the multiplexed circuit is also improved. In some embodiments of the present invention, multiple TDM slots are assigned to a particular signal to reduce the equivalent connection delay caused by the TDM channel for the particular signal. In some embodiments of the present invention, timing simulation is performed using the equivalent delays to avoid the simulation of the TDM hardware; and, the simulation time step does not have to be reduced due to asynchronous clock, resulting in reduced simulation time.

A system and method for time division multiplexing multiple lower bandwidth signals into a high bandwidth signals such as a high-definition television signal. The invention provides an integrated transmission, distribution and routing signal format in which low-bandwidth signals are embedded in the active video and vertical blanking areas of a high-bandwidth signal. Data from the source data streams, including timing data, is formatted in packets, each packet comprising a plurality of channels. The packets are inserted into the high-bandwidth signal along with a header word providing a ‘data valid bit’ or ‘status bit’ for each of the channels, which identifies valid data words within the packet. The source data streams are accurately reconstituted by de-multiplexing according to header data specifying routing destination, stream ID, stream type, channel usage and stream clock reference for clock recovery at the receiving end.

The invention discloses a method and a device for time division multiplexing of a radio frequency resource in a terminal, and the terminal, relates to the field of wireless communication, and can efficiently save network resources and remove influence from call drop records of the terminal to network KPI (Key Performance Indicator). The method for time division multiplexing of the radio frequency resource in the terminal comprises the steps of: receiving a connecting request of a first service sent from a network to a first SIM card; determining whether a second service of a second SIM card is in progress; if the second service of the second SIM card is determined in progress, sending a resource release request of the second service to the network to enable the second SIM card to enter into an idle state; sending a connecting request of receiving the first service to the network to enable the first SIM card to perform the first service. The method and the device for time division multiplexing of the radio frequency resource in the terminal are mainly used in a time division multiplexing process of the radio frequency resource in the terminal.

The invention discloses a method and a system for time division multiplexing of transmitting channels to overcome the defect of lack of using transmitting channel redundancy in a multi-antenna system to reduce transmitting channels. The method includes: using a first group of transmitting channels on a first frequency band to transmit signals to a first geographic region through a first group of antenna units according to a first channel bandwidth in a first time interval; and using the first group of transmitting channels on a second frequency band to transmit signals in a second time interval after the first time interval, or using the first group of transmitting channels on a third group of antenna units to transmit signals, wherein the pass band width of the first channel is smaller than or equal to the width of the first frequency band, and the second frequency band is not identical to the first frequency band. By means of time division multiplexing of transmitting channels among different frequency bands and / or different antenna units, the defect of lack of using transmitting channel redundancy in the multi-antenna system to reduce the transmitting channels in the prior art is overcome.

The invention relates to a multibeam time division multiplexing (TDM) holographic three-dimensional display system and method. The multibeam TDM holographic three-dimensional display system comprises a 4f system, a spatial light modulator, a polarization gating unit, an aperture diaphragm and a control unit, wherein the 4f system consists of a first lens and a second lens; the spatial light modulator is used for inputting computer generated hologram codes and displaying the frequency spectrum distribution of the input codes on a frequency spectrum face corresponding to the spatial light modulator through the conversion of the first lens; the polarization gating unit is used for acquiring orthogonal modulation information of adjacent incident light under a polarization state by combining with the spatial light modulator; the clear aperture of the aperture diaphragm consists of orthogonal polaroids in sequence, and the aperture diaphragm is positioned on the frequency spectrum face which is determined by the spatial light modulator through the first lens; the control unit is used for controlling the incidence sequence and time of the incident light of the spatial light modulator; and the light information is filtered by the polarized aperture diaphragm and then converted through the second lens to reproduce input information of the spatial light modulator on the effective modulation face. By means of the multibeam TDM holographic three-dimensional display system and method disclosed by the invention, the broadened synthesis of diffraction view angles is realized, a real three-dimensional image with a large view angle is displayed, and the practical development of a computer generated hologram three-dimensional display technology is facilitated.

A time division multiplex transmission system transmits information on multiple channels by using a transmission path with variable time division multiplexing. The variable time division multiplex transmission system of this invention is equipped with multiple channel devices 30 and a single transmission path 5 connected to these multiple channel devices. The multiple channel devices 30 transmit or receive data over the transmission path. Additionally, the system is equipped with a circuit that determines consecutive time slots for using the transmission path, and each of the channel devices transmits or receives data using consecutive time slots. Data can be transmitted in two or more different transmission bands, and the different transmission bands are realized by making the number of time slots used for a communication frame different.

The invention discloses a transceiver applied to a time division duplexing TDD system. The transceiver comprises a digital up-conversion unit, a digital predistortion processing unit, a downlink analogue unit, a radio-frequency transceiver unit, an uplink radio-frequency pretreatment unit, a switch, a feedback and uplink share unit and a digital down-conversion unit, wherein the switch conducts electrical passages among the feedback and uplink share unit, the uplink radio-frequency pretreatment unit and the digital down-conversion unit when the transceiver is in a receiving time slot; and the switch conducts electrical passages among the feedback and uplink share unit, the downlink analogue unit and the digital predistortion processing unit when the transceiver is in a transmitting time slot. By applying the invention, a feedback link and an uplink can perform the time division multiplexing on the feedback and uplink share unit, thereby reducing the complexity of the design of the transceiver, reducing the volume of the transceiver and also lowering the cost of the transceiver.

The invention provides a transmission method for uplink control signaling and a base station and user equipment which are used for realizing the same. In the invention, an uplink control channel is divided by at least one of code division multiplexing, time division multiplexing and frequency division multiplexing into one or more of sub-channels for supporting different feedback quantities of uplink control signaling, so that a plurality of sets of user equipment with the same or different uplink control signaling feedback needs can be multiplexed to a time-frequency resource corresponding to the same uplink control channel flexibly. The base station indicates the user equipment dynamically by downlink control channels or semi-statically by high-level signaling to adopt feedback resources of different uplink control channels. When the method, the base station and the user equipment are used, the using efficiency of the uplink control channels can be improved to save loads of the uplink control channels, and the technology of carrier aggregation, collaborative multipoint sending / receiving and multi-antenna enhancement can be supported effectively.

The invention discloses an optical fiber wireless RoF passive optical network realizing method based on an optical code division multiplexing (OCDM). In an optical line terminal (OLT) RoF center station, a signal realizes double-sideband modulation, three paths of generated carrier components are respectively modulated with wired and wireless user data and are not subjected to modulation. The signal is coupled to an optical fiber channel after coded by the OCDM, transmitted to an optical distribution network (ODN) and allocated to each optical network unit (ONU). The ONU carries out OCDM decoding on the received signal, then three paths of components are separated, one path of components is directly sent to a wired user terminal after subjected to photoelectric detection, the other two paths of components enter an RoF base station for carrying out beat frequency to obtain a radio frequency signal, the radio frequency signal is subjected to ECDMA (Electric Code Division Multiple Access) coding and transmitted through an antenna after subjected to electric amplification, and a wireless user terminal obtains a required signal through ECDMA decoding. The invention provides an effective path for realizing wired / wireless secrecy access in a PON (Passive Optical Network) system.

The invention provides a self-adaptive switching method of space division multiplexing and code division multiplexing for a time division synchronous code division multiple access system. One method comprises the following steps: S102, estimating an uplink channel by a node B, and real-timely evaluating the mutual relativity of the space channels of two transmission blocks according to the estimation result; S104, switching to the code division multiplexing mode when the mutual relativity of the space channels is larger than a first threshold, and carrying out throughput evaluation when the mutual relativity of the space channels is smaller than the first threshold; S106, respectively estimating the throughput of the space division multiplexing mode and the code division multiplexing mode by the node B according to the channel quality of the space division multiplexing mode or the code division multiplexing mode fed back by a user terminal, and switching to the space division multiplexing mode if the total throughput of the space division multiplexing mode is larger than a second threshold more than the throughput of the code division multiplexing mode, otherwise, switching to the code division multiplexing mode; and S108, informing the user terminal of the multiplexing mode adopted by the subsequent downlink service channel and the related information by the node B through a downlink control channel.

The invention discloses a time division multiplexing method for hybrid flow fusion, which comprises the following steps of: setting a periodic data sending time slice in a time sensitive network for transmitting periodic data; wherein a pore time slice, namely an aperiodic data sending time slice, is arranged between the adjacent periodic data sending time slices and is used for transmitting aperiodic data; generating a data scheduling scheme in each TDMA period in the periodic data sending time slice and the non-periodic data sending time slice set in the step S1, and recording the data scheduling scheme as a porous scheduling scheme; and sending the periodic data and the non-periodic data by adopting the porous scheduling scheme generated in the step S2 to realize time division multiplexing of the periodic data and the non-periodic data in the time sensitive network. According to the invention, the real-time transmission of the periodic data in the mixed flow of the time sensitive network can be ensured, the periodic data is ensured to have relatively small time delay and jitter, and the service quality of the non-periodic data can also be ensured, so that the periodic data and the non-periodic data can be transmitted in a mixed manner.

A time division multiplex transmission system transmits information on multiple channels by using a transmission path with variable time division multiplexing. The variable time division multiplex transmission system of this invention is equipped with multiple channel devices 30 and a single transmission path 5 connected to these multiple channel devices. The multiple channel devices 30 transmit or receive data over the transmission path. Additionally, the system is equipped with a circuit that determines consecutive time slots for using the transmission path, and each of the channel devices transmits or receives data using consecutive time slots. Data can be transmitted in two or more different transmission bands, and the different transmission bands are realized by making the number of time slots used for a communication frame different.

The invention discloses a time division multiplexing (TDM)-based low-reflectivity triangle spectrum-shaped fiber grating sensing system. The system mainly comprises a distribution feedback laser, an electro-optical modulator, a circulator, an optical amplifier, a triangle spectrum-shaped fiber grating sensor, a high-speed optical detector, a pulse signal generator and a signal acquisition device, wherein the distribution feedback laser is used for emitting narrow line-width laser; pulse signal light is formed by the narrow line-width laser through the electro-optical modulator or is generated by internal modulation through the distribution feedback laser; the pulse light passes through the circulator and then is reflected by a triangle spectrum-shaped fiber grating; the reflected light passes through the circulator to enter the optical amplifier and is amplified into the high-speed optical detector; and a light signal is converted into an electrical signal through the high-speed optical detector, and the electrical signal is converted into a digital signal and is processed through the signal acquisition device. In the system, the distribution feedback laser and the low-reflectivity triangle spectrum-shaped fiber grating sensor are combined, a large-scale fiber grating sensing network is constructed through TDM, and thousands of sensors are multiplexed on a single fiber, so that the costs of a light source and a wavelength detection device are reduced.

The invention discloses a device for compatibly realizing a grouping transmission service and a time division multiplexing (TDM) service, comprising an incoming TDM interface processing unit, an emulation processing unit, an exchange processing unit, a grouping transmission processing unit, an emulation processing unit and an outgoing TDM interface processing unit. The incoming TDM interface processing unit is used for transmitting a de-encapsulated TDM frame payload to the emulation processing unit; the emulation processing unit is used for transmitting an emulated and encapsulated TDM emulation frame to the exchange processing unit; the exchange processing unit is used for transmitting the TDM emulation frame to the grouping transmission processing unit or the emulation processing unit which corresponds to a target outgoing interface; the grouping transmission processing unit is used for encapsulating and processing the TDM emulation frame into a grouping transmission frame and transmitting the grouping transmission frame to a grouping transmission network; the emulation processing unit is used for transmitting a peeled, emulated and emulated TDM frame payload to the outgoing TDM interface processing unit; and the outgoing TDM interface processing unit is used for encapsulating and mapping the TDM frame payload into a TDM frame which corresponds to a type of the target outgoing interface and transmitting the TDM frame to a TDM network. The invention also discloses a device for compatibly realizing the grouping transmission service and a TDM service.

A time-spreading and wavelength-hopping optical encoder spreads each pulse in a modulated optical pulse signal into a predetermined pulse train including pulses with different wavelengths. The last pulse in the pulse train is delayed from the first pulse in the pulse train by an interval that is longer than the pulse period of the modulated optical pulse signal. Interference is avoided by dividing the pulse train into successive delay groups that are equal in length to the pulse period of the modulated data pulse signal, and having each wavelength appear in only one delay group. If encoders producing differently structured pulse trains are used in an optical multiplexer, interference is avoided by having the same wavelength appear only at different positions within the delay groups of different pulse trains. Long delays can be used to multiplex a relatively large number of channels, even at high transmission rates.

A precoding-multiplexing circuit is formed by a precoding circuit for carrying out a precoding with respect to n sets of parallel input binary data signals having a bit rate equal to R / n, to obtain n sets of parallel precoded signals, and a time division multiplexer for time division multiplexing the parallel precoded signals obtained by the precoding circuit, in units of one bit, and outputting time division multiplexed output signal having a bit rate equal to R. In this configuration, the encoding is realized by processing electric signals before the time division multiplexing, so that it becomes possible for the preceding circuit to handle signals which are slower than the transmission rate, and therefore it becomes easier to realize the higher transmission rate.

The invention provides a method and a device for transmitting a time division multiplex (TDM) service. The method comprises the following steps of: encapsulating a predetermined TDM frame signal of a first TDM network side into a grouped data packet; and transmitting the grouped data packet to a packet switching network. Due to the adoption of the method and the device, certain channels and certain time slots in the TDM frame signal can be selectively loaded to a data packet so that the bandwidth utilization ratio of the network can be increased.

A ML simplified detecting method of space division multiplexing in multi-input / multi-output antenna system includes finding out a sending antenna with maximum modulation system when channel parameter is known, carrying out ML exhaustion search on modulation constellation of the other sending antenna then subtracting influence of these antenna signals in received signal and using IF algorithm to demodulate antenna with maximum modulation system, corresponding each ML exhaustion search to one IF demodulation result, finding out an optimum combination and using it as demodulation signal of sending antenna.

A novel power automatic information transmission platform comprises an EPON. The EPON mainly comprises an OLT, an ODN and a user ONU. The novel power automatic information transmission platform overcomes the defects in the prior art and has the advantages that construction, operation and maintenance cost is saved; due to the fact that only passive devices such as an optical fiber and an optical branching device are arranged between the OLT and the ONU, a machine room and a power device do not need to be rented, active devices are not needed, and maintenance staff are reduced; rich bandwidth resources are achieved, namely, the kilomega rate is adopted on both the uplink and the downlink of the EPON, and dynamic bandwidths can be flexibly distributed according to user requirements; the point-to-multipoint structure is adopted, so that convenience is brought for system expansion and updating; the functions of simultaneous transmission and time division multiplexing, IP data and videos and other services are possessed; optical fiber communication is adopted in the whole process, so that the anti-interference capacity is extremely high.

Methods and apparatus for interrogating sets of optical elements having characteristic wavelengths spanning a sweep range while avoiding overlapping reflections from the different sets when performing a wavelength sweep are provided. One example method generally includes introducing a pulse of light, by an optical source, into an optical waveguide to interrogate at least first and second sets of optical elements, wherein the optical elements within each set have different characteristic wavelengths and wherein the first and second sets are separated in time such that a first time window over which light is reflected from the optical elements in the first set and reaches a receiver does not overlap with a second time window over which light is reflected from the optical elements in the second set and reaches the receiver; and processing the reflected light to determine one or more parameters corresponding to the optical elements.

The invention discloses a data transmission method and device, and the method and device are used for solving a problem that the system spectrum utilization rate of a conventional distribution algorithm based on time slot reservation is low because the conventional distribution algorithm employs a mode of time division multiplexing. The method comprises the steps that a first node selects a first time frequency resource occupied by the first node from time frequency resources, corresponding to a condition that the first node is a spare sub-band, from a time slot which can achieve frequency division multiplexing, and carries out the data transmission on the first time frequency resource, wherein at least one time frequency resource, except the time frequency resource occupied by the first node, on the time slot which can achieve frequency division multiplexing serves as a second time frequency resource occupied by the second node, and the spatial isolation degree between the first node and the second node is less than the minimum spatial isolation degree that the nodes capable of reusing the same time frequency resource need to meet, and is greater than the maximum distance that nodes with the communication demands need to meet, thereby achieving the frequency division multiplexing of the time slot between at least two nodes without communication demands.

Provided are an Optical Network Unit (ONU) for low latency packet transmission in a Time Division Multiplexing-Passive Optical Network (TDM-PON), a method of operating the ONU, and an apparatus for controlling the ONU. The method includes: receiving, from a base station, first bandwidth allocation information regarding a bandwidth allocated by the base station to a terminal for uplink packet transmission; and transmitting a bandwidth allocation request, which is based on the received first bandwidth allocation information, to an Optical Line Terminal (OLT) before completing packet reception from the base station.

Apparatuses and methodologies are described that enhance performance in a wireless communication system using beamforming transmissions. According to one aspect, the channel quality is monitored. Channel quality indicators can be used to select a scheduling technique, such as space division multiplexing (SDM), multiple-input multiple output (MIMO) transmission and opportunistic beamforming for one or more user devices. In addition, the CQI can be used to determine the appropriate beam assignment or to update the beam pattern.