摘要:
A method for improving the performance of a random access communications system in a variable radio environment is disclosed, whereby at least one valid set of burst signatures is used for transmission by one or more mobile stations. Each set includes at least one signature with a different signature-length than the signatures in other sets. The different signature-lengths can be optimized for the operational environments involved (e.g., longer signatures for slower-moving mobile stations, and shorter signatures for high-speed mobile stations). Alternatively, at least one differentially-encoded signature is used for random access transmissions, in order to reduce the radio channel's sensitivity to large doppler spreads and frequency errors.
摘要:
A set of different pilot structures are designed for use in different environments and/or different user behaviors that are expected to occur in a cell. The radio conditions for a user are estimated. Each user is then assigned an area (108A-E) in resource space for its communication, which has a suitable pilot configuration. In one embodiment, the entire resource space is provided with different pilot structures in different parts (110A-D) In advance and allocation of resources to the users are then performed in order to match estimated radio conditions to the provided pilot structure. In another embodiment, allocation is performed first, and then the actual pilot structure is adapted within the allocated resource space area to suit the environmental conditions.
摘要:
The technology disclosed provides the ability for a subframe to be configured as a “flexible” subframe. As a result, at least three different types of subframes in a TDD system may be configured: a downlink (“DL”) subframe, an uplink (“UL”) subframe, and a “flexible” subframe. While the DL and UL subframes are preconfigured for each frame instance, the flexible subframes are dynamically allocated to be an uplink subframe in one instance of a frame and a downlink subframe in another instance of the frame.
摘要:
A set of different pilot structures are designed for use in different environments and/or different user behaviours that are expected to occur in a cell. The radio conditions for a user are estimated. Each user is then assigned an area (108A-E) in resource space for its communication, which has a suitable pilot configuration. In one embodiment, the entire resource space is provided with different pilot structures in different parts (110A-D) In advance and allocation of resources to the users are then performed in order to match estimated radio conditions to the provided pilot structure. In another embodiment, allocation is performed first, and then the actual pilot structure is adapted within the allocated resource space area to suit the environmental conditions.
摘要:
A set of different pilot structures are designed for use in different environments and/or different user behaviours that are expected to occur in a cell. The radio conditions for a user are estimated. Each user is then assigned an area (108A-E) in resource space for its communication, which has a suitable pilot configuration. In one embodiment, the entire resource space is provided with different pilot structures in different parts (110A-D) In advance and allocation of resources to the users are then performed in order to match estimated radio conditions to the provided pilot structure. In another embodiment, allocation is performed first, and then the actual pilot structure is adapted within the allocated resource space area to suit the environmental conditions.
摘要:
A system and a method for wireless linking in a cellular communication system are disclosed such that a mobile station is maintained in simultaneous communication with at least a first node and a second node for access to the cellular communication system. Information going to and from the first node is not identical to the information going to and from the second node. In one embodiment the second node, or secondary access point is a relay node forwarding received information to and from the first node, or primary access point. In another embodiment the second node is another mobile station performing a direct mobile-to-mobile communication (MS-to-MS). In still an embodiment a first wireless link to the first node is for control information only. In still a further embodiment a second wireless link to the second node is only for communication of information from the mobile station or only for communication of information to the mobile station.
摘要:
In a system applying orthogonal frequency division multiplexing, OFDM, a number of carriers are reserved for communication between unsynchronized nodes (N1, N2). At least one such reserved carrier is assigned to each base station. A sinusoidal signal is transmitted on this reserved carrier during a time period at least equal to two consecutive OFDM symbols. The unsynchronized receiver detects the sinusoidal signal during one of two consecutive OFDM symbol time periods. The existence, the frequency and the signal power of the signal give information about the existence and identity of the transmitter. Also, estimates of relative velocities and distances can be deduced. In preferred embodiments, the sinusoidal signal can also be used to transmit further information by using signal modulation or coding that is independent of the absolute signal phase.
摘要:
The present invention relates to a method and an arrangement for communicating packet information in a digital telecommunications system. Through the invention is selected a set of designated communication resources (ch1-chn) from an available amount of resources. Every packet (P) is forward error correction encoded into an encoded packet (Pci), via one of at least two different coding schemes (ci), prior to being transmitted to a receiving party, over the designated communication resources (ch1-chn). An estimated transmission time is calculated for all combinations of coding scheme (ci) and relevant distribution (dj) of the encoded data blocks (B1-B&Ggr;), in the encoded packet (Pci) over the set of designated communication resources (ch1-chn), and the combination (ci,dj) is selected, which minimises the estimated transmission time.
摘要:
The object of the present invention is to provide a mechanism for a more efficient carrier search. The object is achieved by a method for sending a signal in a first node. The first node communicates with a second node via radio communication, which radio communication is performed by multi carrier transmission. The first node uses a carrier, being associated with a frequency range. The method comprises the step of transmitting an end-marker signal within or close to the frequency range. The end-marker signal is intended to be received and used by the second node for identifying the frequency range of the used carrier.
摘要:
Radio resources are allocated to communication between a mobile station and a base station. The available set of radio resources may comprise radio resources primarily assigned to a neighboring cell if the 5 mobile station experience an instantaneous low level of co-channel interference from such neighboring cells. The existence of interference is preferably deduced from signal quality measurements of pilot signals. The allocation may concern uplink and/or downlink communication. Devices for performing the measurements are located in the mobile station, while devices for performing the evaluation, selection and actual allocation can be placed in different parts of the communications system-in the mobile station, in a base station or in a core network node, or as a distributed means.