80 results about "Cognitive base station" patented technology

The present application relates to of the communication field and discloses a method, device and system for implementing frequency point shift based on CR. The method comprises: determining, by a cognitive base station, a candidate working frequency point for UE deployed in a cognitive frequency band; then sending to the UE broadcast information which at least carries the candidate working frequency point and instructing the UE to shift from the working frequency point currently used thereby to the candidate working frequency point by way of a frequency point shift command. In this way, the UE deployed in the cognitive frequency band can achieve frequency point shift quickly and accurately according to the instruction from the cognitive base station when an authorized user accesses the working frequency point currently used by the UE, effectively avoiding interference to the authorized user and thereby ensuring the service performance and service continuity of the system. The present application also discloses a corresponding device and system.

The invention relates to a game type selection-based method for realizing dynamic spectrum allocation. With the development of the wireless communication technology, the traditional fixed spectrum allocation mode which leads to the waste of resources and has low spectrum utilization rate, has become the key factor of limiting the further development of the wireless communication network. The cognitive radio-based dynamic spectrum allocation technology is considered as a key technology for effectively solving the problem. In the method of the invention, by comparing the perfect dynamic game with the return of Nash Bargaining, the cognitive base station and the secondary user can separately choose an optimal strategy flexibly and fairly, namely an optimal spectrum quoted unit price and a spectrum purchase quantity. Meanwhile, in order to realize the selection operations of the both sides, a simple spectrum access procedure is designed to be compatible with the traditional mobile call access procedure. By adopting the invention, the returns of the cognitive base station and the secondary user can be effectively increased and the spectrum utilization can be promoted.

The invention relates to a cognitive SIMO network access method based on cooperative relay, wherein a cognitive base station collects channel responses in a network and judges whether the cognitive users can cooperate with a primary user to achieve the target transmission rate required by the primary user or not, if so, a cognitive SIMO network is accessible to a frequency band licensed to the primary user; otherwise, the cognitive SIMO network is non-accessible. The access method can enable a plurality of the cognitive users and the primary user to simultaneously use the same licensed spectrum in the same geographical position, on the premise of ensuring the target transmission rate of the primary user, and further improve the utilization efficiency of the spectrum as far as possible. As the access method is based on cooperative communication, the nearer the distance from the cognitive network to the primary network is, the greater the network throughput can be achieved; and furthermore, a large-range network coverage can be realized, so the deficiencies in the existing cognitive radio access ways are made up.

The invention discloses a dynamic cognitive network resource allocating method, and belongs to the technical field of wireless communication. The occupied situation of a master user authorization frequency band is predicted based on master user historical information and service characteristics, a cognitive base station carries out subordinate user frequency spectrum and power joint optimization allocation according to the frequency spectrum prediction information and subordinate user service requirement information, and therefore maximization of the subordinate user joint energy efficiency and minimization of the number of switching times are achieved. According to the method, the occupied state of the cognitive network master user frequency band, the subordinate user service requirement and switching cost caused by frequency band switching are comprehensively taken into consideration, the joint resource allocation is carried out based on a network energy efficiency maximization criterion, and the subordinate user joint energy optimization is achieved while the subordinate user service requirement is guaranteed and the performance drop caused by switching is reduced.

The invention discloses a proportional fairness resource distribution method of a cognition OFDM system based on spectrum lining. The proportional fairness resource distribution method of the cognition OFDM system based on spectrum lining comprises the steps that a cognition base station obtains channel state information needed by resource distribution; the cognition base station carries out proportional fairness resource distribution on the frequency and power resources through a firefly method; the cognition base station initializes the parameters of the firefly method and determines the target function value of fireflies; the relative brightness and attractiveness of the fireflies in a group are determined, and the firefly position where the target function value is the maximum is determined; the spatial position vector of the fireflies is updated; whether the newly generated firefly position meets the limitation conditions is detected, if yes, the next step is carried out, and if not, the last step is carried out again; the detection is repeated and the optimal solution of frequency and power resource distribution is output; the cognition base station informs a cognition user of the resource distribution result. The proportional fairness resource distribution method of the cognition OFDM system based on spectrum lining distributes the resources from the two dimensions of frequency and power according to the proportional fairness principle, and provides technical support for efficiently using wireless resources and improving throughput.

A cognitive terminal includes different types of radio modules suiting to different types radio media employed by a cognitive base station in the radio communication system. The radio module of the cognitive terminal counts the number of times it receives / transmits ACK / NACK in each unit time. A radio environment cognition unit of the cognitive terminal performs calculations using the count number(s) in consideration of the packet transmission time interval or the time required for repeating a single data packet, thus measuring characteristics of delay time variations in uplink / downlink communication with respect to each radio media. Thus, it is possible for the cognitive terminal to switch over radio media based on ACK / NACK in uplink / downlink communication.

The present invention relates to a spectrum switching method based on a reputation system in a cognitive heterogeneous wireless network. For the problem that selfish or malicious behaviors of secondary users in a spectrum switching process cause degradation of network performance, firstly, the behavior of a secondary user after accessing a channel is evaluated by extracting user behavior characteristic information, a reputation value is determined according to the behavior of the secondary user, and a reputation system is established on a cognitive base station; secondly, the secondary user isranked according to a reputation status of the secondary user, and a licensed channel or a channel of an ISM frequency band is allocated to the secondary user according to the ranking situation of the secondary user; and finally, in a process of accessing a licensed spectrum, when a requirement for a waiting delay of a user is met, the secondary user with a high reputation value has a higher access priority. A simulation result shows that the method can effectively improve system throughput, reduce probability of switching and interruption, reduce the chances to access the licensed spectrum by secondary users with low reputation, and improve system security.

The invention discloses a low-power-loss multi-channel spectrum sensing method and system facing a cellular communication network. The method comprises the steps that first, a channel management entity selects a shared spectrum which is divided into a plurality of channels; second, the channel management entity divides the channels into a plurality of channel clusters in a frequency domain, during spectrum sensing, an asynchronization silent period is used for channels in different channel clusters, a synchronization silent period is used for channels in the same channel cluster; third, during the silent period, a cognition user terminal completes corresponding spectrum sensing operation in a current cell according to control of a cognitive base station, sensing results are reported to the cognitive base station, the cognitive base station integrates the sensing results and reports the sensing results to the channel management entity; fourth, the channel management entity refreshes state information of all of the current channels in each cell according to the integrated sensing results and feeds the information back to the base station. The frequency of spectrum sensing by the system is reduced, and accordingly power loss is lowered.

The invention relates to a resource allocation algorithm in LTE-R based on recognition. The algorithm comprises the following steps: step one, providing a novel multi-purpose state action set form a dual-target optimization problem of throughput and resource block switching frequency in the LTE-R; step two, providing an exploratory method for a second exploration and utilization balance problem, wherein the performance of the cognitive base station for balancing the exploration and the utilization is better in the process of comparing with a greedy decision method, thereby proving the necessity of environment exploration in the LTE-R cognitive wireless network; and step three, introducing the specific application scene of the embodiment of the invention, discovering that two values in thealgorithm of the invention have respective emphasis on influencing different optimization targets, finding a group of appropriate values, thereby enabling the performance of the system to be more excellent in comparison with other values. Furthermore, the application scene further proves the effectiveness of performing spectrum management in the base station of the LTE-R environment.

The invention discloses a multi-user cognitive MIMO (Multiple-Input Multiple-Output) system concurrent transmission and user scheduling method based on IAC (interactive application communication). The method comprises the following steps that: (1) an authorized user and an authorized base station obtain channel information H0, cognitive users obtain channel information H0, Hi and H<s>i, and a cognitive base station obtains all channel information; (2) the authorized user, the authorized base station, the cognitive users and the cognitive base station respectively implement singular value decomposition on the H0; (3) all the cognitive users respectively calculate an intermediate matrix norm value, and the cognitive user with the maximum value is selected to be scheduled; (4) the cognitive base station gives notice to the scheduled cognitive user SUxi, and the authorized user and the cognitive user SUxi respectively construct a precoding matrix P0 and a precoding vector pxi; (5) data of the authorized user and the activated cognitive user are respectively pre-treated by P0 and pxi and then are sent to a base station; (6) the authorized base station solves a primary data stream x01 of the authorized user and sends the primary data stream x01 to the cognitive base station; (7) filter waves are received by utilizing F<H>, x01 is removed from a received mixed signal, a secondary data stream x02 of the authorized user and a data stream x(xi) of the cognitive user are respectively solved, and x02 is sent to the authorized base station.