291results about How to "Reduce co-channel interference" patented technology

A system, method, and software are provided for measuring co-channel interference in a wireless network with particular application for management of resource allocation for Non Line of Sight (NLOS) wireless backhaul in MicroCell and PicoCell networks. Given the difficulty of predicting the mutual interference between multiple links, DownLink and UpLink co-channel interference are characterized between each Hub and each Remote Backhaul Module Unit periodically during active service. Beneficially, the co-channel interference metrics are used as the basis for intelligently and adaptively managing network resources to substantially reduce interference and increase the aggregate data capacity of the network e.g. by grouping of interfering and/or non-interfering links, and managing resource block allocations accordingly, i.e. assigning common resource blocks preferentially to weakly interfering links or groups of links and allocating different resource blocks or orthogonal channels to strongly interfering links or groups of links.

A novel and useful apparatus for and method of single antenna interference cancellation (SAIC) in a wireless communications system. A class of algorithms for Downlink Advanced Receiver Performance (DARP) receivers based on a novel metric calculation used during equalization and optionally in other portions of the receiver as well such as soft value generation. A DARP receiver for 8PSK EDGE modulation is presented wherein the interfering signals comprise GMSK modulated signals In accordance with the invention, the modified metric is adapted to take into account the rotation remaining in the noise component of the received signal after de-rotation of the 8PSK signal. Considering the interferer to be a GMSK signal, the I/Q elements of the noise are correlated and this fact is used to modify the decision rule for the received signal thus improving the performance of the equalizer. The model is further extended to take into account temporal error correlation.

Apparatus and methods for improving the throughput and capacity of a wireless communications network. In one embodiment, this improvement is accomplished by focusing upon reduction of the co-channel interference, including the interferences that are unpredictable or undetectable to a traditional network. Various implementations detect the receiver interference (i.e. the interference affecting the receiver performance) at the transmitting node in order to avoid or reduce its effect at the receiving node. This detection can be as simple as e.g., spectral sensing constituting power measurement, and/or can be more sophisticated such as measurements including bandwidth, duty cycle and statistical behavior of the unwanted signal.

The invention discloses a ground-air broadband wireless communication system and a method for an airplane. The system comprises a plurality of long term evolution (LTE) ground base stations installed along a predefined airway and an LTE communication terminal on the airplane, wherein an overlapping communication coverage area is arranged between adjacent LTE ground base stations, the base stations perform wireless launch and receiving according to an LTE wireless air interface protocol, and the LTE communication terminal performs wireless launch and receiving according to the LTE wireless air interface protocol to build high-speed two-way communication links with the ground base stations; and additionally, a plurality of airplane radio frequency antennas are arranged on the outer surface of the airplane and connected with the LTE communication terminal through interconnection wire cables. Each ground base station is provided with radio frequency antennas with the same polarization, the radio frequency antennas with the same polarization are directional antennas with a certain beam broadband, and the LTE communication terminal receives radio frequency signals launched by the ground base stations and launches radio frequency signals to the ground base stations through the plurality of airplane radio frequency antennas.

The invention discloses a distribution method for frequency source of wireless system which includes: every section reports the information that indicates the load state or the needed frequency source periodically; it decides the needed frequency source according to the reported information from sections, and judges the needed frequency source is bigger than the fixed frequency source which belongs to the section, if yes, the spare frequency source of adjacent sections is distributed for the section. The invention also provides the corresponding frequency source distribution device and wireless communication system. The invention can adjust the main frequency source that occupied by the boundary users according to the different load requirement of sections, it can avoid the disturbance between the section and improve the throughput of section boundary.

Multiple field units in a CDMA system are synchronized for communication with a base station using shared forward and reverse link channels. In an illustrative embodiment, each field unit is assigned a time slot in a forward link channel to receive messages from the base station. Likewise, each field unit is assigned a time slot on a common reverse link channel for transmitting messages to the base station. Timing alignment and power level control among each of many field units and the base station is achieved by analyzing messages received at the base station in a corresponding time slot as transmitted by each field unit. Thereafter, a message is transmitted from the base station in a corresponding time slot to a particular field unit for adjusting its timing or power level so that future messages transmitted from the field unit are received in the appropriate time slot at the base station at a desired power level. In this way, minimal resources are deployed to maintain communication and precise synchronization between a base station and each of multiple users, minimizing collisions between field units transmitting in adjacent time slots on the reverse link. This method reduces the frequency a field unit must rely on the use of a slotted aloha random access channel according to IS-95.

The invention discloses a real name authentication method and an authentication platform of wireless networks in a wide range of public places. The authentication method includes that a mobile terminal is connected with a wireless network; the mobile terminal is relocated to an entry page, provides the mobile terminal with identity authentication modes of mobile phone number authentication, artificial customer service foreground authentication and certificate self-help scanning authentication; obtains an internet account and a password after the identity is authenticated; and logs on the internet in the entry page through the internet account and the password. The real name authentication method and the authentication platform of wireless networks in a wide range of public places can provide quick and convenient identity authentication for wireless network users in a wide range of public places, and solve the problem that wireless networks in large wide range of public places cannot provide large number of users with quick and convenient real name internet service.

The method of invention provides a multicast service from an information delivery apparatus to wireless terminals through wireless routes. The method includes the step of transmitting, from the information delivery apparatus, a plurality of sets of multicast information, wherein these sets are identical to each other as to contents thereof but differ in transmission conditions. The method further includes the step of receiving, at any given one of the wireless terminals, one of the sets of multicast information being transmitted under one of the differing transmission conditions.

The invention relates to a downlink transmission frequency division method for cooperating a multipoint transmission CoMP system on the basis of service quality, comprising the steps: a base station differentiates the type of ordered services so as to carry out frequency division according to test data from a user terminal, and also selects cell set participating in cooperative transmission according to the acquired information of the base station adjacent to the cell and according to the receiving power of detected signals; when subcarriers are distributed, the base station set time delay limit of signal transmission firstly, then the transmission time delay and the time delay limit of signals are compared, and real-time users and non-real-time users are differentiated; then the subcarriers are distributed according to the proportion fairness principle, and the feedback of the user terminal is received; firstly the user terminal for the real-time service acquires the substrates with good transmission quality according to the QoS priority order of the users; and then the remaining subcarriers are distributed to the user terminal for non-real-time service. In the downlink transmission frequency division method, not only are different requirements of users for bandwidth and time delay solved, the interference among the users of adjacent cells is also reduced, and the performance of edge-cell users is also improved.

Provided are systems and methods for minimizing co-channel interference on-board a satellite. An up-link signal received by the satellite is post-compensated, where the up-link signal includes a desired signal transmitted by a first transmitter and an interfering signal transmitted by a second transmitter. The post-compensating includes identifying the interfering signal based on post-compensation parameters. In addition, a down-link signal to be transmitted from the satellite to a receiver is pre-compensated. The pre-compensation process includes determining gain relations between a gain of a first satellite antenna which transmits the down-link in a direction of the receiver and a gain of a second satellite antenna which transmits an interfering signal in the direction of the receiver, sampling and scaling interfering signals at the satellite based on the gain relations, and estimating a co-channel down-link interference component that the down-link signal is expected to experience on a path to the receiver.

The method comprises: the base station allocates the dedicated resources for the edge users, and ensures an overlapping between the user-dedicated resources in adjacent cells or sectors; user monitors and detects the downlink signals of current cell and sector or adjacent cell and sector, which contains flag information, to get downlink signal detection information; estimating the anti-interference status of user and the interference to the users in adjacent cell or sector; according to the result, allocating the right of using the resources, and then scheduling and allocating the resources; finally, adapting the uplink of user.

The invention discloses a coordinated beamforming method for coordinated multiple point transmission (CoMp) downlink cells in a long term evolution-advanced (LTE-A) system, which mainly solves the problems of low throughput and co-channel interference of edge users among cells. The method comprises the following realization steps that: (1) a base station utilizes pilot frequency to obtain a channel matrix from the base station to users and resolves a related matrix; (2) the base station performs singular value decomposition on the related matrix according to a maximum signal-to-noise ratio criterion to resolve an eigenvector corresponding to a maximum eigenvalue of the related matrix; (3) a codon with the shortest distance from the eigenvector is found in a codebook space; (3) the base station finds a codon in a codebook according to a criterion of minimum user leakage signal; (4) whether the codons are the same is judged, if so, a beamforming vector of the users is found, and otherwise, operation of the next step is performed; and (5) a codon, the sum of the distances from which to the two codons is smallest, is found in the codebook space and taken as the beamforming vector of the users. The method can improve the average throughput of the edge users of the cells when effectively controlling leakage signal energy of the edge users of the cells, which inhibits the co-channel interference among the edge users of neighboring cells.

A dynamic channel distribution method for the asymmetric up and down services suitable for CDMA access system includes: in a time division duplex system of a fixed-length frame based on variable up-and-down time slot, channel resources are formed containing the variable time slot or time frequency zones and code channels, the network decides if re-allocating the resources information. When the time slot is decided to be re-distributed, the system divides shared time slots, time frequency zone, prior time slot or prior time frequency zones for primaries needing them and each primary determines itself if the prior time slot or prior time frequency zones are used in the transmission of up or down line.

The invention discloses an inter-cell interference coordination method adopting three-dimensional beam forming in a 3D-MIMO (three dimensional multiple-input multiple-output) system. Different types of users distributed in three-dimensional space are dispatched in different time slots, meanwhile, a three-dimensional beam forming transmission technique is used, and inter-cell same-frequency interference borne by the users is greatly reduced. The inter-cell interference coordination method comprises the following steps: (1) an apex angle from each base station to a direct-sight path of each user is calculated according to the distribution of the users in the three-dimensional space, and the users are separated into high-riser users and low-riser users accordingly; (2) the low-riser users are separated into cell edge users and cell center users according to the plane positions of the users in a cell; (3) the time slots of the dispatched users are divided into three kinds, the same kind of users are dispatched by all the base stations in each kind of time slots, the three-dimensional beam forming transmission technique is used to serve the users, power of useful signals received by the users is further increased, and interference is reduced. The inter-cell interference coordination method greatly improves the service quality of the cell edge users while improving the overall network throughput capacity.

The invention discloses a method for allocating optimal power of an MIMO-OFDM multi-user system based on power allelism of uplink power and a downlink power of a wireless channel, a user apparatus and a communication system, which are applied to the technical field of wireless transmission. A transmission terminal apparatus realizes multi-user dispatching of a downlink broadcast channel and minimizes power consumption of the transmission terminal under a restricted condition of satisfying velocity requirements of multiple users according to channel conditions of various users; the user apparatus and the transmission terminal apparatus can realize conversion of an allocation scheme of the optimal allocation of the downlink power and the allocation of the uplink by using the relation of the power allelism of the uplink and the downlink. The invention provides the power allocation method for minimizing the transmission power on the premise of satisfying the velocity requirements of various users, therefore, power overhead of the transmission terminal is reduced, and a purpose of reducing interference of inter-users and inter-cells is also achieved.

The invention discloses a configuration method for single frequency network area, which is used to realize dynamic and semi-static configuration of single frequency network area. The method is: multicast coordinate entity MCE receives message sent by multimedia broadcast and multicast service MBMS wireless resource application entity; the mentioned MCE determines whether to expand single frequency network area based on the message, and ensure MBMS wireless resource application entity that needs to be added into single frequency network area; and sends wireless resource assigning information to MBMS wireless resource application entity that needs to be added into single frequency network area. The invention also discloses a communication system, MCE, MBMS wireless resource application entity and user device.

A method of frequency hopping is supported by a basestation having a broadband transceiver. The method permits changing physical channels upon which mobile subscribers communicate with the basestation, wherein the broadband transceiver is operated using static transceiver frequencies, the method exclusive of switching communication signals between transceivers. In one embodiment, the method maps baseband output signals from a digital channelizer which represent physical channels to ones of digital signal processors representing logical channels and baseband input signals of a digital combiner to ones of logical outputs of digital signal processors according to a mapping signal.

The invention discloses a frequency point selection method as well as household base stations and equipment. The frequency point selection method comprises the following steps: determining the interference strength of a target base station on each frequency point, and traffic loads of other base stations except the target base station on each frequency point; and determining the operating frequency point of the target base station in accordance with the interference strength of the target base station on each frequency point and the traffic loads of the other base stations except the target base station on each frequency point. The frequency point option method can be used to optimize frequency selection policies of cells in the household base stations, thereby reducing same frequency interference among the cells in the household base stations.

The invention discloses a method and a device for allocating power to a downlink control channel, and a base station. By the invention, the power is dynamically allocated to the downlink control channel, the reasonableness of allocating the power to the downlink control channel is improved, the receiving performance of the downlink control channel of each user is improved, and same frequency interference among cells of the downlink control channel is reduced. The method comprises the following steps of: determining the received signal-to-noise ratio of the downlink control channel of the user according to downlink channel information of the user; determining the target signal-to-noise ratio of the downlink control channel of the user; and determining the transmitting power of the downlink control channel of the user according to the received signal-to-noise ratio and the target signal-to-noise ratio. Due to the technical scheme, the reasonableness of allocating the power to the downlink control channel of the user is improved, so that the receiving performance of the downlink control channel of each user is improved, and the same frequency interference among the cells of the downlink control channel is reduced.

In a time division multiple access communication system, adjacent and co-channel interference are reduced by discontinuing or shutting off modulation of carrier frequency signals during inactive time slots so that transmitted power of carrier frequency signals are reduced. Also, the time slots and carrier frequency signals are organized so that each carrier frequency signal has the least amount of time slots designated as active time slots. The time slots are designated so that the respective same time slots of adjacent carrier frequency signals are not concurrently designated as active time slots.

In a cellular radio system down-link diversity is provided. The system has means in a base station (BS) for receiving signals from a mobile station (MS) using a diversity reception arrangement, in particular an antenna diversity arrangement (207, 209). Information regarding the current reception conditions is extracted from the reception diversity system and is used for improving the transmission. Thereby the transmitted signals can have less signal power, which in turn makes it possible to provide smaller cluster sizes and thereby increase the channel capacity in the cellular radio system.