China Academy of Telecommunications Technology

Telefonaktiebolaget Lm Ericsson (publ)

Wenling Bai

Yu Yang

Chenggang Jiang

Yuanyuan Li

Zhuo Gao

Jinling Hu

Ruiping Wei

Qiubin Gao

Xueming Pan

Yuan Wang

Yang Hu

Xin Tong

Libo Wang

Guojun Xiao

Xiaolu Wang

Dongsheng Sang

Yeming Tang

Wenwen Liu

Juan Serrato Vital

Mats Åhlander

A method and an apparatus for obtaining timing advance value. The method comprises: receiving (S) a time domain signal, which contains at least part of a reference signal; extracting (SI), from the time domain signal, a first group of signal parts including at least one signal part, and a second group of signal parts including at least one signal part, wherein the first group of signal parts do not overlap the second group of signal parts; and determining (S) a timing advance, TA, value based on an energy of a signal part in the first group of signal parts and an energy of a signal part in the second group of signal parts, wherein the energy of the signal part is based on correlation between the signal part and the reference signal. Therefore, the TA value may be obtained based on a time domain signal.

Method and apparatus for obtaining timing advance value

A method performed by a communication node and an apparatus for operating the method are proposed. The method includes obtaining matched filter channel estimation associated with a user equipment (UE); obtaining first Timing Advance (TA) compensated channel estimation; obtaining first noise suppressed channel estimation; and obtaining first TA estimation associated with the UE based on the first noise suppressed channel estimation.

Method and apparatus for estimating and compensating timing advance

Various examples of the present disclosure describe a method for configuring a quiet period in a CR system and a device thereof. The method includes: determining, by a base station, a maximum value of a quiet period parameter of a CR system based on maximum duration of interference which a radio authorization system tolerates and maximum loss of capacity which the CR system tolerates; determining a sensing algorithm based on a detecting performance requirement and the maximum value of the quiet period parameter; determining a value of the quiet period parameter based on the sensing algorithm; and sending the quiet period parameter to a terminal of the CR system. When the examples of the present disclosure are employed, the rationality of the configuration of the quiet period parameter of the CR system is improved and the capacity loss of the CR system is reduced when the interference to the authorization system is reduced.

Method for configuring quiet period in cognitive radio system and device thereof

The present disclosure provides a dynamic spectrum allocation method and a dynamic spectrum allocation device. In the method, a centralized node performs spectrum allocation and transmits a spectrum allocation result to each communication node, so that the communication node operates at a corresponding spectrum resource in accordance with the spectrum allocation result and performs statistics of communication quality measurement information. The centralized node receives the communication quality measurement information reported by the communication node, and determines whether or not it is required to trigger the spectrum re-allocation for the communication node in accordance with the communication quality measurement information about the communication node. When it is required to trigger the spectrum re-allocation, the centralized node re-allocates the spectrum for the communication node.

Dynamic spectrum allocation method and dynamic spectrum allocation device

A method and device for determining available spectrums is disclosed in embodiments of the present invention. By applying the technical solution of the embodiments of the present invention, with consideration on the bi-directionality of the interference between wireless communication systems, when introduction of the cognitive system is required, the corresponding frequency will be determined as an available frequency only in the case the incumbent system and the cognitive system can be simultaneously guaranteed to meet the corresponding coexistence criterion among the corresponding frequency and adjacent frequencies thereof, thus ensuring that the determined available frequency band guarantees that the normal operation of the incumbent system is not interfered by the cognitive system while ensuring that the newly-introduced cognitive system can also operate normally without interference of the incumbent system, thereby improving the communication quality of the wireless communication systems.

Method and device for determining available spectrums

The cognitive radio cell acquires a scheme dividing frequency band resources into a number of sub-bands and corresponding silent period time frequency pattern, when performing silence on the sub-band which the cognitive radio cell works on according to the silence period time position of each sub-band defined in the silent period time frequency pattern, spectrum sensing on corresponding sub-band is implemented by radio spectrum sensing system or cognitive radio cell.

Method and device for spectrum sensing in cognitive radio system

Various examples provide a method and a system for spectrum handover in cognitive radio (CR) systems. According to the method, after detecting a user of an authorized system appears at a current working frequency, the base station generates a spectrum handover command and sends the spectrum handover command via a channel identified by the CR DWNDI to instruct the UEs in the cell to perform spectrum handover according to the spectrum handover command.

Method and system for spectrum handover in cognitive radio networks

Embodiments of the present application relate to the field of wireless communications, and in particular, to a method and an apparatus for cell search in a sensor system, used for solving the problem in the prior art that an operation time delay is long in cell selection and cell residence. The method of the embodiments of the present application comprises: a terminal determining different types of frequency points in frequency points supported by the sensor system, the frequency points of the sensor system being divided, in a diminishing sequence of priorities, into a first type of authorization frequency point, a first type of non-authorization frequency point, a second type of authorization frequency point and a second type of non-authorization frequency point; and performing, in a diminishing sequence of priorities, cell search and cell residence on the frequency points supported by the sensor system. With the present application, a suitable cell can be selected fast and accurately to perform residence, thereby reducing the operation time delay in cell selection and cell residence after a terminal is started, and improving user experience.

Method and apparatus for cell search in sensor system

Disclosed are a method and device for determining and assisting in determining a back-up frequency in a cognitive radio system. A first cognitive system shares the wireless communication spectrum resources of an incumbent system, and the method thereof for determining a back-up frequency comprises: through a terminal, a first cognitive system obtaining a back-up frequency of a second cognitive system which has overlapping coverage in a target area in an overlapping coverage area; and according to the back-up frequency of the second cognitive system in the overlapping coverage area, selecting from the wireless communication spectrum resources at least one frequency as a back-up frequency in the target area. When determining the back-up frequency, the first cognitive system can refer to the back-up frequency of the second cognitive system to conduct determination, thereby optimizing the system performance.

Method and device for determining and assisting in determining back-up frequency in cognitive radio system

The embodiments of the present application relate to the technical field of wireless communications, and in particular to a method, system and device for triggering and performing spectrum sensing, used for solving the problem in the prior art that if the sensing period is set too long, a decline of service quality between an authorization system and a cognitive system or even a network paralysis will be caused due to interference; and if the sensing period is set too short, an increase in power consumption of devices and a waste of spectrum resources will be caused. The method for performing spectrum sensing in the embodiments of the present application includes: a sensing node judging whether or not the channel quality has declined to the requirement for performing in-band spectrum sensing; and after determining that the channel quality has declined to the requirement for performing in-band spectrum sensing, the sensing node performing in-band spectrum sensing. By way of applying the embodiments of the present application, the problems of decline of service quality between an authorization system and a cognitive system or even a network paralysis due to interference caused by setting the sensing period too long, or an increase in power consumption of devices and a waste of spectrum resources caused by setting period too short, can be avoided.

Method, system and device for triggering and performing spectrum sensing

Various examples of the present disclosure describe a random access method and device in a CR system. The method includes: generating, by a base station device, a spectrum handover command, wherein the spectrum handover command comprises random access backoff time parameter information; and sending, by the base station device, the spectrum handover command to a user equipment in a cell to instruct the UE to initiate, during a spectrum handover procedure, a random access procedure using the random access backoff time parameter information. According to the various examples of the present disclosure, the random access backoff time parameter information is carried in the spectrum handover command, so that a random access conflict is suppressed during the spectrum handover procedure of the CR system. A large number of UEs that intensively perform random access on a target working frequency are pre-dispersed in time. As such, the delay and the failure probability of the random access on the target working frequency during the spectrum handover procedure are reduced, and thus the failure probability of the spectrum handover and the service interruption time are reduced, so that the user experience of the CR system is improved.

Random access method and device in cognitive radio system

The present application relates to of the communication field and discloses a method, device and system for implementing frequency point switch 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 switch from the working frequency point currently used thereby to the candidate working frequency point by way of a frequency point switching command. In this way, the UE deployed in the cognitive frequency band can achieve frequency point switch quickly and accurately according to the instruction from the cognitive base station when an incumbent user accesses the working frequency point currently used by the UE, effectively avoiding interference to the incumbent user and thereby ensuring the service performance and service continuity of the system. The present application also discloses a corresponding device and system.

Method, device and system for implementing frequency point switch based on CR

The present disclosure provides a method and an apparatus for obtaining an idle spectrum. The method includes: obtaining, by a central management unit, configuration information of a transmitter of an authorized system, and obtaining geographic location information of candidate sense nodes; selecting, by the central management unit, sense nodes from the candidate sense nodes according to the configuration information and the geographic location information, and informing the selected sense nodes to perform spectrum sensing; and receiving, by the central management unit, sensing results of the selected sense nodes, and obtaining information of an idle spectrum according to the sensing results.

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Beijing, China

Wenling Bai