83results about How to "Optimize transmit power" patented technology

The invention provides a power control method and equipment. The method comprises the steps that a base station acquires a power adjustment value of user equipment (UE) in an uplink channel according to a reference signal for measuring downlink loss by the UE and the transmitting power of the reference signal in each wave beam; and the base station transmits the power adjustment value to the UE through one or two signals, wherein the power adjustment value is used for adjusting the transmitting power of the uplink channel by the UE, is different from a power control value corresponding to a transmit power control (TPC) command, and is used for compensating deviation of the downlink loss measured based on the reference signal from practical link loss of the uplink channel; and the TPC command is a TPC command in downlink control information (DCI) which is transmitted by the base station to the UE. The method solves the problem of mismatched uplink transmitting power resulting from the difference between the link loss value measured by using the downlink reference signal and the practical link loss value of the uplink channel in the prior art.

The invention discloses a D2D resource allocation method based on multi-agent deep reinforcement learning, and belongs to the field of wireless communication. The method comprises the following steps:firstly, constructing a heterogeneous network model of a cellular network and D2D communication shared spectrum; establishing a signal to interference plus noise ratio (SINR) of a D2D receiving userand an SINR of a cellular user based on the existing interference, respectively calculating unit bandwidth communication rates of a cellular link and a D2D link, and constructing a D2D resource allocation optimization model in a heterogeneous network by taking the maximum system capacity as an optimization target; For the time slot t, constructing a deep reinforcement learning model of each D2D communication pair on the basis of the D2D resource allocation optimization model; And respectively extracting respective state feature vectors from each D2D communication pair in the subsequent time slot, and inputting the state feature vectors into the trained deep reinforcement learning model to obtain a resource allocation scheme of each D2D communication pair. According to the invention, spectrum allocation and transmission power are optimized, the system capacity is maximized, and a low-complexity resource allocation algorithm is provided.

An access point for a radio communication system transmits a pilot signal. The access point can operate in different modes with the pilot signal transmit power being controlled differently. A mode processor (105) controls a pilot signal controller (103) such that when in a first mode the access point is arranged to vary a pilot signal transmit power in accordance with a first transmit power profile. Another mode processor (107) controls the pilot signal transmit power in accordance with a second profile in a second mode. The transmit power may be constant during the second mode. A transition processor (111) is arranged to transition the access point from the first mode to the second mode in response to receiving an access request for a remote station.

The invention relates to the field of wireless communication, in particular to an energy efficiency optimization method for a wireless body area network. The energy efficiency optimization method for the wireless body area network comprises the steps of A analyzing the characteristics of the body area network and a path channel loss model and determining a work mode; B establishing an energy consumption minimization model and a network life cycle maximization model; C carrying out simulation and performance analysis on the energy consumption minimization model and the network life cycle maximization model. The energy efficiency optimization method for the wireless body area network has the advantages of establishing the network life cycle maximization model more according with practical application, verifying an optimal distribution method through simulated analysis, improving energy efficiency, and obtaining an optimal network life cycle.

The invention discloses a multi-user collaboration jamming power distribution method under the restraint of confidentiality interrupt probability in a wireless wiretap channel. The Alice-1 user emits useful signals to an expected receiving end Bob, and remaining K-1 users emit collaboration jamming signals, and the wiretap end Eve of a single antenna wiretaps information sent by the Alice-1 user. By means of the method, the secure communication rate is improved by optimizing the emitting powers of all the jamming users, and the physical layer safe communication in the wireless wiretap channel is achieved.

The invention discloses a power distribution method based on MIMO-NOMA short packet transmission. According to the method, a short packet transmission related theory is adopted for the first time, andthe remote user communication quality in the MIMO-NOMA system is analyzed; and on the premise of ensuring the communication quality of the near users, the sending power and the maximum reachable transmission rate of the users in the cluster are jointly optimized by utilizing an alternating iterative algorithm, and finally, the power distribution method capable of realizing the maximization of thethroughput of the far users is obtained.

The invention discloses a D2D communication resource allocation method in a relay cooperative heterogeneous cellular network, comprising the following steps: solving the maximum achievable rate threshold R<Q(n),n><dmax>of D2D communication in a frequency band n when each cellular user n adopts a communication mode Q(n); judging whether spectrum resources selected for D2D communication can meet the requirement of the quality of service of a system according to R<Q(n),n><dmax>; jointly allocating the achievable rate target R<Q(n),n><d> allocated for D2D communication in the frequency band n when the cellular user n adopts the communication mode Q(n), and determining the communication mode Q(n) of each cellular user n; and solving the total transmitting power Ptotal of the system. By adopting the method, the transmitting power of cellular users and D2D users and the optimal achievable rate target of D2D users in each frequency band can be optimized at the same time, and the communication mode of each cellular user in the system can be determined. Compared with a traditional resource allocation method, the method can reduce the total power consumption of the system while ensuring the achievable rate of cellular users and D2D users, and is more in line with the requirement of green communication.

The invention relates to a 3D MIMO beamforming method with robustness in a multi-cell OFDMA network, and belongs to the technical field of communication. The 3D MIMO beamforming method comprises the steps that an uncertain constraint condition is converted into a probability model according to a channel error model and through the chance constraint optimization method, a probability constraint condition is converted into a certain constraint condition through statistical distribution of fading channels, and finally a distributed beam forming algorithm is proposed to optimize the transmitting power of a base station. Compared with the prior art, under the condition of the non-perfect channels and the angle influence of users in 3D MIMO in the horizontal direction and the vertical direction, the service quality is guaranteed for the users through the distributed algorithm, the total transmitting power of the base station is minimized, and therefore the purpose of saving resources is achieved.

The present invention provides a method, a mobile terminal device and a system for determining a transmission power factor. During an uplink of data between a mobile terminal device and a base station via a code division multiple access (CDMA) system supported by automatic repeat request (ARQ) first transmission containing original data and re-transmissions of different order containing supplementary information are communicated. The i-th re-transmissions are based on the automatic repeat request (ARQ). The transmission power factor to be determined is operable with an i-th re-transmission. A first and a second error quantity are obtained from an evaluation of status information items received in accordance with the automatic repeat request (ARQ). The first error quantity and the second error quantity allow for deriving an i-th error ratio so as to calculate a transmission power correction factor.

A signal generation system suitable for use in a radar system comprises a local oscillator (LO) and an intermediate frequency IF oscillator, wherein the IF oscillator is a Direct Digital Synthesiser, and the LO is a free runn ing oscillator not itself locked to another oscillator but which acts as a c lock reference for the DDS and is the highest frequency oscillator in the sy stem. The LO may also act as a reference for a receive chain digitiser. The invention exploits phase noise advantages of a free running oscillator at so me distance from the carrier whilst maintaining coherency with other system components. The system typically finds application in FMCW radars.

The invention discloses an energy harvesting D2D communication resource allocation method based on reinforcement learning. In the method, a D2D sending end directly communicates with a D2D receiving end by adopting a mode A, or communicates with the D2D receiving end by applying an NOMA technology while adopting a mode B as a relay to assist cellular communication. Firstly, an outage probability expression when a user adopts different modes for communication is deduced; and then it is assumed that energy collection and channel state information at all moments are known, channels are allocatedfor the D2D users and relays are selected for the cellular users by utilizing a KM algorithm, and the sending power of the D2D users is optimized by utilizing a reinforcement learning method by considering energy causality constraints and maximum sending power limits. According to the method, the D2D sending end is considered to be capable of serving as a relay to assist edge cellular user communication, resource allocation of D2D users and cellular users is optimized under the condition that user service quality and energy constraints are met, the total capacity of the D2D users and mode B cellular users can be improved, and more edge cellular users are allowed to have access to a network.

The invention discloses a transmitting method and a receiving method for an uplink signal, a terminal and a base station. The transmitting method comprises the steps that: a terminal receives a downlink signaling issued by the base station, a waveform used by the terminal is determined according to the downlink signal, the terminal determines a power difference corresponding to a target time-frequency resource according to correlations between waveforms and power differences so as to determine the uplink transmission power of an uplink signal mapped on the target time-frequency resource according to the determined power difference, and the terminal transmits the uplink signal at the power, wherein the target time-frequency resource refers to either an OFDM symbol multiplexed by an RS and achannel or an RE of a mapping channel in the OFDM symbol multiplex by the RS and the channel. The embodiments, by reducing the transmission power of the uplink signal on the target time-frequency resource, achieve a reduced OFDM symbol multiplexed by the RS and the channel, thus allowing a power-limited terminal to transmit data normally and optimizing transmission power utilization of the power-limited terminal.

The invention provides a multi-terminal direct link joint power control method based on a geographical spectrum database, comprising the steps as follows: acquiring the position information of each user, using a model to calculate the loss value of each link, and initializing the transmission power value of each user; calculating the signal-to-interference plus noise ratio (SINR) value of a primary user receiving end and judging whether the SINR value is within a reasonable range; calculating the theoretical transmission power value of a secondary user in each D2D link when the throughput of the D2D link is maximized; and calculating the optimal transmission power, and performing iterative operation according to the judgment on the SINR value of the primary user receiving end. According to the invention, coordinate coexistence of the links of multiple secondary users is fully considered, the total throughput of a system composed of the secondary user links is maximized by reasonably controlling the power of each secondary user, and the capacity of the system composed of the secondary user links can be further increased.

The invention provides a power distribution method of channel sharing for large-scale users in an uncertainty condition of a channel. The method includes: calculating the link loss between secondary users; calculating the mutual interference between the secondary users and the sum of the throughputs of all the secondary users; calculating the optimal emission power in each secondary user link in accordance with the secondary user peak value power constraint and the interference constraint between the secondary users; and substituting the optimal emission power into a primary user constraint condition for verification, determining the fact that the optimal emission power is the most reasonable emission power if the interference constraint condition of a primary user is satisfied, otherwise, reducing the optimal emission power for one step, and re-substituting the optimal emission power into the primary user constraint condition for verification until the most reasonable emission power is found. According to the method, in the uncertainty condition of the channel, the power distribution method for maximizing the total throughput of the secondary users can be searched.

In order to relieve network pressure caused by sudden increase of local flow in an emergency communication scene, the embodiment of the invention provides a data distribution method and device in an edge cache. The method guarantees high-spectral-efficiency low-delay data distribution during multi-service concurrence, and comprises the following steps: dividing terminal users into a plurality of NOMA groups according to a data distribution mode, namely direct transmission or relay, stored by an edge node, and each NOMA group comprises a direct transmission user and a relay user; the pluralityof NOMA groups are divided into two types according to different channel conditions from the direct transmission users and the relay users to the edge nodes, the channel conditions of the direct transmission users of the first type being good, otherwise, the channel conditions of the direct transmission users of the second type being good; the successful distribution probability of the NOMA groupof the first category and the NOMA group of the second category is determined; and the sending power and spectrum resource allocation of the edge nodes are optimized by taking the maximization of thesuccessful distribution probability of the whole network as a target. According to the invention, the requirements of multiple users for data can be met efficiently, and the probability of successfuldata distribution is improved.