115 results about "Full duplex relay" patented technology

An apparatus and method for interference cancellation and synchronization maintenance over interference channel estimation in a communication system are provided. An interference channel estimator fixes synchronization and estimates an interference signal. An interference signal controller eliminates the estimated interference signal from a received RF signal. A synchronization unit unfixes fixed synchronization and tracks synchronization when the interference signal cancellation is stable. A data buffer stores data from which the interference signal is canceled.

An apparatus and method for adaptively adjusting a target Received Signal Strength Indicator (RSSI) for Automatic Gain Control (AGC) in a full-duplex relay apparatus with an interference cancellation function. A Signal to Interference Ratio (SIR) estimation block estimates an SIR based on an interference signal estimated from a received signal and an interference-cancelled signal determined by cancelling the estimated interference signal from the received signal. A target RSSI determination block determines a target RSSI according to the estimated SIR. An AGC block adjusts a gain for the received signal based on the determined target RSSI.

Frame structures, a method and an apparatus for resource allocation in a wireless communication system based on a full duplex relay are provided. The method for a centralized resource allocation in the wireless communication system based on the full duplex relay includes receiving channel information from a plurality of mobile stations (MSs) and relay stations (RSs); scheduling radio resources for a link between a base station (BS) and the MS and a link between the BS and the RS using the channel quality; constituting a first radio resource region for the link between the BS and the RS and a second radio resource region for the link between the BS and the MS; and scheduling radio resource for a link between the RS and the MS by reusing the first radio resource region. The relay link resource is reused in the full-duplex relay structure, and the system capacity can be raised by minimizing the interference in the resource utilization.

Embodiments of the present invention are systems and methods for wireless communication. According to one embodiment, a system for wireless communication comprises a first relay station, second relay station, and a base station. The first relay station and the second relay station are operable to receive and transmit wireless signals. The base station is operable to transmit the wireless signals to the first relay station and the second relay station in an interchanging pattern during successive time frames so that the first relay station and the second relay station forward the wireless signals to a mobile station.

The invention discloses a power control method embedded into a D2D cellular network and based on a time domain half-duplex relay, and belongs to the technical field of wireless communications. The method relates to a base station B using a point-to-multipoint topological structure cellular network for transmitting, a cellular network receiving terminal C, a D2D transmitting terminal R used as a cellular communication relay and a D2D receiving terminal E; the D2D transmitting terminal is used as a cellular communication relay between the base station B and the receiving terminal C, cellular communication and D2D communication are subjected to combined power control, the full-duplex wireless relay technology is used for achieving orthogonal communication channel frequency spectrum multiplex of the cellular communication and the D2D communication, the minimum data throughout requirement of the cellular communication is met, meanwhile, the throughout of the D2D communication is maximized, hence, the overall performance of the system and the individual performance of users can be considered at the same time, and good balance can be achieved between the system layer and the user layer.

The invention discloses a power distribution method for a full-duplex relay network in a nonideal channel state, and belongs to the technical field of wireless communication. The method gives consideration to a safe and effective capacity model in a full-duplex multi-carrier safety system with an intercept unit. A resource distribution task in a safety network of a full-duplex multi-carrier relay is completed through a robust full-duplex relay loop interference channel state information method. Therefore, the method achieves the planning of optimization problems of power limit, affected by the total power and the loop of the full-duplex relay, and safe and effective capacity maximization. The method solves an optimal dual factor through a Lagrange duality theory, so as to achieve the optimal power distribution strategy. The optimal power distribution method enables the full-duplex relay network in the nonideal channel state to meet the requirements of upper users for quality of service (time delay QoS), and also achieves the optimal safety performance and the high-efficiency utilization in a supposed channel state information error range.

The invention discloses an artificial noise precoding secure transmission method for a full duplex relay system. The method comprises the following steps: an information source adopts an artificial noise precoding scheme to simultaneously broadcast useful signals and artificial noise signals; a relay receives the signals broadcast by the information source and the self-interference at the relay, and a wiretapper receives the signals broadcast by the information source and recoding signals transmitted by the relay; a relay node reduces the influence caused by the self-interference by adopting a self-interference elimination technique; an information sink receives the transmitted signals that are recoded by the relay by adopting a maximal-ratio combining strategy; the signal to interference and noise ratios of the information source to a relay link and the relay to an information sink link are obtained, and the received signal to interference and noise ratios at the information sink and the wiretapper are also calculated; and the instantaneous safety rate of the system is obtained according to the received signal to interference and noise ratios at the information sink and the wiretapper, and an average safety rate is calculated. According to the method disclosed by the invention, the legal channel transmission rate can be increased, and the capacity of wiretap channels can also be effectively reduced.

The invention relates to a power distribution method for a full-duplex multi-carrier safety system based on QoS requirements, belonging to the technical field of wireless communication. In the full-duplex multi-carrier safety system including interception, a spectrum sharing mode is used as a communication mechanism; on the basis of the safety effective capacity, upper-layer user QoS limitation (time delay QoS) is introduced through a cross-layer joint optimization method; furthermore, in the event that different time delay QoS limitations are satisfied, requirements of performance optimization and resource utilization maximization of the full-duplex multi-carrier safety system are satisfied; therefore, the optimization problem of maximizing the safety effective capacity under the limitation of the total power and the full-duplex relay loop interference power is planed; and optimal dual factors are obtained through a Lagrangian duality theory, such that an optimal power distribution task is realized. By means of the optimal power distribution method, the full-duplex multi-carrier safety system satisfies requirements of the upper-layer user QoS (time delay QoS) requirements, and particularly realizes the optimization of the system safety performance and the high efficiency of physical layer resource utilization.

The invention provides a construction method of a full duplex relay system based on sparse code multiple access, and belongs to the field of communications. The invention aims to solve the problem of difficulty in meeting the requirements of spectrum efficiency and transmission rate in 5G in a conventional OFDMA (Orthogonal Frequency Division Multiple Access) system, and further provides a construction method of an interference cancellation full duplex relay system based on the sparse code multiple access. The construction method of the full duplex relay system based on the sparse code multiple access is implemented by the following steps that: I, a user A<J> encodes information in a sparse code multiple access way, and transmits the encoded information to a relay station; II, the relay station receives and transmits the information in a full duplex way, performs interference cancellation on self-feedback interference, and forwards the information to a user B<J>; and III, the user B<J> performs corresponding decoding after a signal forwarded by the relay station is received in order to obtain the information transmitted by the user A<J>. The construction method is suitable for the field of communications.

The invention discloses a power control method in D2D communication based on full duplex relay. The power control method comprises the following steps: a cellular network base station B allocates time-frequency resources in which each D2D link and a cellular link are orthogonal to each other; when a terminal S and a terminal D hope to perform communication in a D2D mode, a base station B selects a suitable full duplex decoding forwarding relay R for the D2D link, and then the base station B compares the maximum energy efficiency of the D2D link based on the full duplex relay with the maximum energy efficiency of the direct connection D2D link through power control conditions on the premise of guaranteeing that the transmitting power of the terminal S and the terminal R does not exceed the maximum value, and selects a mode with high energy efficiency to perform the communication. The power control method disclosed by the invention is conducive to improving the spectral efficiency, expanding the application range of the D2D technology, unloading the burden of the base station to a greater extent, considering the balance between the transmission rate and the power consumption, ensuing more flexible selection of the communication mode of the D2D link and better satisfying the requirements of green communication in actual communication systems.

The invention provides a cooperative control method for transmitting power of a gateway and terminals in a hierarchical M2M network, and relates to the field of wireless communications. The cooperative control method for the transmitting power of the gateway and the terminals is realized by establishing a wireless communication link by employing full duplex relay transmission, obtaining channel state parameters (the expression is shown as in the description) and (the expression is shown as in the description) of a wireless M2M gateway, calculating a channel gain in the network after obtaining the channel state parameters (the expression is shown as in the description) and (the expression is shown as in the description) of wireless M2M terminals, and calculating a transmitting power control parameter in the case that the data throughput of each wireless M2M terminal is satisfied. Proportions of signal power to interference noise power, namely, signal to interference plus noise ratios from the terminal to a gateway link and from the gateway to a base station link are effectively improved, so that the energy consumption of the M2M terminals is minimized, the minimum time delay requirements of M2M communication are satisfied, and the utilization rate of spectrum resources of a cellular network is effectively improved.

The invention discloses a relay selection method and device for a full-duplex relay system. The method comprises the steps of: on the basis of a DF protocol, pre-setting an optimal relay selection scheme and three sub-optimal relay selection schemes according to channel state information in the full-duplex relay system; performing analytical calculation of the four relay selection schemes, so that the interruption probabilities corresponding to the various relay selection schemes are respectively obtained; performing simulated analysis of simulation factors by adopting a computer, so that the performance states of the four relay selection schemes under the practically measured channel environment are obtained; and, selecting one sub-optimal relay selection scheme, the performance state of which is closet to the performance state of the optimal relay selection scheme in the three sub-optimal relay selection schemes, as the practical relay selection scheme in the full-duplex relay system. The purposes of effectively improving the system performance and the user service quality and saving the equipment cost can be achieved.

The invention relates to a mobile edge computing network resource allocation method based on full duplex relay, and belongs to the field of mobile edges. The method comprises the following steps: constructing an uplink mobile edge computing network model assisted by a full duplex relay; analyzing transmission characteristics of the constructed system, jointly optimizing a user matching strategy, auser task unloading coefficient and transmission power when constraints such as user computing task delay, user outage probability, user maximum computing power and maximum transmitting power are met, and establishing a system total energy consumption minimization optimization problem; decomposing an original non-convex optimization problem into two deterministic convex optimization sub-problemsto be solved by utilizing a worst criterion and an alternate iteration method. According to the method, the pressure of executing tasks with large calculation data volume and low time delay request bythe user can be effectively relieved, the service quality of the user is improved, and compared with the prior art, the consumption of executing the calculation tasks can be effectively reduced, theinterruption probability of the system is reduced, and the stubborn performance of the system is improved.

The present invention discloses an orthogonal frequency division multiplexing (OFDM) co-frequency co-time full duplex relaying method, which solves the problem that the complexity of a relay node is increased due to processing remaining loop interference in the prior art. The method of the present invention comprises the steps of: (1) estimating parameters of a channel; (2) modulating a source signal by a source node; (3) forwarding an emission signal of the source node by the relay node; (4) receiving the emission signal of the relay node by a destination node; and (5) decoding a receiving signal by the destination node. The method of the present invention has the advantage of simplifying the processing procedure of the relay node, improves the signal interference noise ratio of the receiving end of the destination node to the maximum possible extent, reduces the complexity of the relay node, and improves the reliability of a full duplex relay cooperative communication system.

The invention discloses an energy efficiency optimization method based on a full-duplex bidirectional relay D2D network. The method comprises a cellular user, a pair of full-duplex D2D users multiplexing the frequency band of the cellular user, and one full-duplex bidirectional relay user assisting with D2D communication. By use of a double-layer alternative iteration optimization algorithm, the transmission power of the cellular user and the full-duplex D2D users and the amplification gain of the full-duplex bidirectional relay user can be dynamically adjusted, the influences exerted by interference between the users and self-interference of the full-duplex users on network performance are effectively alleviated, and the energy efficiency of a system can be maximized under the constraints of minimum frequency spectrum efficiency. During communication of the cellular user, the full-duplex relay-assisted D2D users can share the frequency band of the cellular user for direct communication, by use of cellular network basis configuration, same-time same-frequency D2D communication and cellular communication are realized, power consumption of the cellular communication is reduced, the energy efficiency of a cellular network is effectively improved, and the method is applied to communication environment with requirements for high density and low power consumption.

The present invention provides an optimal power distribution and relay deployment method of a full duplex bidirectional decoding forwarding relay based on a channel statistics characteristic. The method comprises the following steps of establishing a bidirectional full duplex relay communication system; using a terminal node to send the state information to a relay node, wherein the state information comprises the emission power information and the self-interference information; after the relay node receives the state information of the terminal node, selecting an optimal power distribution scheme to send a signal; and selecting the deployment position of the relay node according to an optimal power optimization scheme. According to the present invention, and according to a deployment mechanism of the relay node, a power distribution mechanism of the relay node enables the interruption probability of a system to be reduced effectively, the problem that the interruption probability is overhigh in a full duplex system is solved, and the stability of the system is improved, thereby improving the service quality of the terminal node.

The invention relates to a full-duplex repeater, a full-duplex relay transmission control method and system. The full-duplex relay transmission control method comprises steps of: acquiring energy acquisition information, energy storage information, and the historical information of each channel state; according to the historical information of each channel state, the energy acquisition information, the energy storage information, and channel state predictive information, determining optimal values of operating mode selection, transmission power adjustment, and target node selection by using iterative computation and using system maximum throughput as an optimization objective so as to derive the operating state decision information of an energy storage device and further control the operating state of the energy storage device. The method and the system may achieve full-duplex energy acquisition and enable a full-duplex energy acquisition system to supply power to full-duplex relay in order to prevent relay from frequently switching between an on state and an off state and further increase system throughput.

A method and an apparatus for canceling an interference in a mobile Full Duplex Relay (FDR) are provided. A signal is received from a base station, interference canceling that uses a transmitter interference signal from which an original signal interference has been cancelled is repeatedly performed on the signal received from the base station, and an interference-cancelled signal is transmitted.

The invention provides a power shunting method for synchronous wireless information and power transfer of a full duplex relay, wherein the power shunting method belongs to the field of wireless transmission. The power shunting method for synchronous wireless information and power transfer of the full duplex relay is used for a full duplex relay network, and a power-shunted relay transceiver architecture is utilized. The power shunting method comprises the steps of acquiring energy by a full duplex relay node from a received RF signal of a source node, thereby realizing wireless full duplex information relaying; power shunting based on total information state information, namely using state information of a first-hop channel, a second-hop channel and a relay loop channel, determining an optimal power shunting ratio through a principle for maximizing an end-to-end SINR or a principle for minimizing a system interception probability; or power shunting based on partial information state information, namely using the state information of the first-hop channel and the relay loop channel, determining an optimal power shunting ratio through the principle for maximizing the end-to-end SINR or the principle for minimizing the system interception probability.

The invention discloses a physical layer security control method based on power allocation in a full duplex relay system. The method comprises the following steps: working in a full duplex mode on thebasis of a relay node, simultaneously sending, by a source node and the relay node, signals, simultaneously receiving, by an eavesdropping node, the signals of the source node and the relay node, andconstructing a signal model; establishing a function relationship between the sending power of the source node and the relay node and system security capacity, namely a constrained optimization function using it as a constraint condition that the sending power of the source node and the relay node is smaller than the maximum sending power and using the maximum system security capacity as the target; when the constraint condition of the sending power of the relay node is not considered, obtaining an optimal sending power expression of the source node, and converting the constrained optimization function into a single-variable constrained optimization function; and finding a feasible solution of the optimal relay sending power by using numerical solution and dichotomy to obtain the expression of the optimal sending power of the relay node. By adoption of the security control method, the physical layer security of the full duplex relay system can be improved.

The invention provides an optimal power allocation method for increasing safe energy efficiency in bidirectional relay networks, comprising the steps of first, performing process modeling for the two-way full-duplex relay network communication, and then considering to design the most optimized power allocation factor under limited conditions of the total power so that safety energy efficiency is maximized in order to improve the safe energy efficiency of the power-limited full-duplex bi-directional relay network.The method considers the energy efficiency that can be maximized under the limited conditions of total power and protects the users' information is decoded by the untrusted relay nodes as much as possible. In addition, the method simplifies the calculation process by Taylor expansion and simplifies operation to bring the estimated error of not more than 6%, which is negligible.

The invention provides a position optimization method for full-duplex relay cooperative communication, and belongs to the technical field of communications. The relay is in a full-duplex mode and adopts a decoding and forwarding strategy, the outage probability of a system is calculated using a direct link and residual self-interference when the relay forwarding delay is more than 1, and an optimal relay position is found by optimization. Experiments prove that the outage probability of the system is gradually increased with increase of the residual self-interference or reduction of the intensity of the direct link, and the optimal relay position moves to a source node with increase of the residual self-interference or improvement of the intensity of the direct link. The method can effectively utilize the information transmitted by the direct link, and significantly improves the spectral efficiency under the system model relative to the existing method taking the direct link as interference.

The invention belongs to the field of mobile communication, and particularly relates to the field of cognitive radio full-duplex relays in mobile communication. The SNR estimation method takes a CU as a full-duplex AF relay of a PR, a point-to-point channel between a PT and the PR becomes a three-node relay channel, receiving signals of the PR is composed of two portions: one portion is direct transmission link signals from the PT, and the other portion is relay link signals from the CU. When the amplitude gain of the CU is large enough, a second hop link signal of the relay becomes very strong, thus the signals of a direct transmission link can be neglected, and the CU and the PR has the same SNR at the moment. Therefore, the CU obtains the SNR of the PR through measuring the SNR from PT signals received by the CU. CLPT is adopted, the PT automatically maintains the SNR at the PR end as a target SNR, the SNR measured at the CU end equals the target SNR of the PR, namely a main link SNR. The SNR estimation method can effectively estimate the target SNR of the link when a G value is large.

An apparatus and method for avoiding interference between a base station and a relay station when using full duplex relay in a multi-hop relay wireless communication system are provided. An operation of a mobile station includes measuring an strength of a receive signal from a base station and an strength of a receive signal from an relay station, calculating a receive signal strength ratio of base station to relay station by dividing the strength of the receive signal from the base station by the strength of the receive signal from the relay station, determining if interference occurs using the receive signal strength ratio, and transmitting a control message representing if interference occurs.