60 results about "Cognitive relay" patented technology

The invention discloses a power distribution method used in a cognitive wireless relay network. In the method, a bilateral cognitive wireless network based on amplifying and forwarding relaying protocols is used as a main body. The bilateral cognitive wireless network includes a master user, two secondary users and N relay nodes. On the condition that the power of each node is limited, the suboptimal power distribution method based on the Cauchy-Schwarz inequality enables the system capacity of the secondary users to be maximized and guarantees the service quality of the master user in the whole communication process. Different from a traditional relay network resource allocation method, the Cauchy-Schwarz inequality is introduced into the method, an iterative method is avoided, the calculation complexity is greatly reduced, and the performance approaching to an optimal power distribution method based on an IPM is achieved.

The invention provides a design method for a secondary user network linear transceiver with a cognitive relay network. The design method comprises the following steps: designing a linear precoder for each secondary user source terminal transmitter to eliminate the interference from the secondary user transmitter to a master user; designing a linear receiver for each secondary user target receiving terminal to eliminate the interference from the master user to the secondary user receiver; and designing beam forming for each secondary user relay to eliminate the interference from the relays to the master user and the mutual interference among secondary users, and maximizing the throughput of the secondary users. The design method can simultaneously eliminate the interference from the secondary users to the master user and the mutual interference among the secondary users, and maximize the throughput of the secondary users. The design method has no limitation for the number of the users and the relays, wherein the number of the users and the relay is greater than or equal to 1. The design method is suitable for the cognitive relay network comprising a single user and a single relay network and any number of the user relays.

The invention discloses a joint resource allocation method of a cognitive relay wireless sensor network, and belongs to the technical field of wireless communication. In the cognitive relay wireless sensor network based on the SWIPT, a sensor subsystem collects energy from a main user signal, and at the same time, the use right of a part of authorized frequency spectrum is exchanged by helping toforward the main user signal so as to transmit a signal of the sensor subsystem. According to the resource allocation method, the power division ratio, the transmitting power allocation and the subcarrier allocation of the sensor nodes are subjected to joint optimization allocation, so that the purpose of maximizing the throughput of the sensor subsystem is achieved, and meanwhile, the target raterequirement of the main system is also considered. The method has the advantages that the throughput of the sensor subsystem can be maximized by reasonably utilizing the energy collected by the sensor nodes and reasonably deploying the subcarriers, so that the system performance is improved.

The invention provides a QoS-based transmission method in a cognitive relay system. The method includes the steps of acquiring a preset number of service transmission source nodes with the highest priority, forming an information channel set according to the preset number of service transmission source nodes with the highest priority, selecting the source node needing the largest bandwidth according to the information channel set, distributing an information channel to the source node needing the largest bandwidth, and selecting a suitable relay node for a destination node according to the distributed information channel. According to the QoS-based transmission method in the cognitive relay system, the source node needing the largest bandwidth is selected from the preset number of service transmission source nodes with the highest priority, and the information channel is distributed to the source node needing the largest bandwidth; services are transmitted through the information channel distributed to the source node, a relay is selected for service transmission of the source node according to an information channel coefficient matrix, therefore, bandwidth requirements are met, user time delay is minimized, the error rate of the system is reduced, and QoS requirements of a user are met on the whole.

The invention discloses a selection method of a cognitive network path. The method comprises the following steps: a secondary user source node, a secondary user relay node and a secondary user destination node respectively obtaining various parameters required for analyzing outageperformance of the cognitive network under mutual interference scene of a primary userand a secondary user, establishing an outage probability closed form expression of any one path in a cognitive relay network under a Rayleigh fading channel in combination withinterference limitation allowed by a primary user receiver end, selecting an optimal path of information transmission from a source node to the destination node in the network according to the optimal criterion of system end-to-end outage performance, and selecting a network path by using minimum standard of the cognitive network outage probability. The technical scheme disclosed by the invention gives full consideration to interference factors of the primary user to the secondary user in the cognitive network path selection and takes corresponding measures so as to improve the reasonability of timely selecting the cognitive network path.

The present invention discloses a multimedia communication cooperative multicast transmission method in a cognitive radio network. The method comprises a first step that a main network sends parameter information to a cognitive relay; a second step that a maximum data bit amount of users in a multicast group is calculated; a third step that the main network determines whether the bit amount of a basic layer meets requirements, if not, a fourth step is carried out, if yes, a fifth step is carried out; the fourth step that the main network combines a cooperative transmission time proportion and a cooperative power that are determined finally, a main user uses a front alpha i part to transmit basic layer data, and a cognitive user uses the left (1-alpha i) part to transmit its own information; the fifth step that the main user uses a front alpha j part to transmit basic layer data, and the cognitive user uses left (1-alpha j) part to transmit its own information; and a sixth step that whether the frame is finished is determined, if not, the second step is carried out, if yes, transmission of the frame data is finished. Through adoption of the method, the system throughput of the main network can be improved effectively, the cognitive network transmission opportunities are increased, the transmission reliability and stability are high, and the method can be applied to a cognitive radio multimedia cooperative multicast system.

The invention belongs to the technical field of wireless communication, and discloses a cognitive user access method and system in a cognitive relay network based on mixed NOMA. No direct transmissionlink exists between the main user transceiver and the cognitive user transceiver. A relay node is needed to assist forwarding, when a main user and a cognitive user perform transmission in a NOMA mode, the target rate of the main user and the target rate of the cognitive user need to be met at the same time, at the moment, the cognitive user and the main user share spectrum resources, and if thetarget rate of the main user cannot be met at the same time in the NOMA mode, the main user transmits the spectrum resources independently. In order to improve the access opportunity of cognitive users, a strategy of combining dynamic power distribution and a dynamic decoding mode is adopted. According to the method provided by the invention, the problem that the cognitive user accesses the authorized frequency band of the main user in the corresponding scene can be effectively solved.

The spectrum sensing and information transmission method with energy collection in the cognitive wireless network of the present invention, the cognitive user uses the signal from the main user transmitter to perform spectrum sensing and energy collection, and uses the collected energy for information transmission, and detects the main user In the user phase, the cognitive user and N cognitive relays jointly detect whether the primary user is occupying the spectrum. In the stage, according to the final decision result of spectrum sensing, cognitive users perform energy collection or information transmission. While obtaining high spectrum sensing performance, the present invention provides working energy for the cognitive user, prolongs the service life of the cognitive user, and reduces or does not need periodic battery replacement.

The present invention provides a QoS-based transmission method in a cognitive relay system, comprising: obtaining the source nodes of the highest priority preset value transmission services, and according to the highest priority preset value source nodes of the transmission services , to form a channel set, select and allocate a channel for the source node according to the channel set, and select a suitable relay node for the destination node according to the allocated channel. The present invention provides a QoS-based transmission method in a cognitive relay system, and selects the source node with the largest required bandwidth for the source nodes of the highest priority preset value transmission services, and allocates a channel for the source node; Transmit services through the channels allocated for the source node, and select relays for the source node transmission services according to the channel coefficient matrix, thereby ensuring bandwidth requirements, minimizing user delays, and reducing the bit error rate of the system as a whole. Guarantee the user's QoS requirements.