Abstract: Systems and techniques for handover management between adjacent cells. A base station, such as a macro base station serving a macro cell identifies a user device as a candidate for handover based on specified criteria and communicates a handover request to a femto base station. The femto base station evaluates specified conditions, such as energy efficiency, for the cell it is serving and allows the handover only if the handover would improve the conditions.

Abstract: There is provided a solution for reusing radio resources opportunistically by private base stations to increase the overall capacity of the network. The solution is based on applying an uplink broadcast in a mobile communication, in which information representing a radio resource allocated by a base station to a user terminal is broadcasted.

Abstract: A method includes sending a message from a first to at least one second cognitive radio apparatus to determine a channel to be used for sending data from the first to the second radio apparatus, the message sent over a first channel and comprising an advertisement of at least one second channel for use in sending the data from the first to the second radio apparatus, the advertisement comprising a corresponding proposition/evaluation bit for each second channel, receiving a reply from the second radio apparatus over the first channel, comprising an acceptance of one of the second channels with the corresponding proposition/evaluation bit, a rejection of the second channel and an advertisement of a third channel, or a rejection of the second channel without an advertisement of a third channel, and transmitting the data from the first to the second radio apparatus over an agreed upon second or third channel.

Abstract: A method includes sending a message from a first to at least one second cognitive radio apparatus to determine a channel to be used for sending data from the first to the second radio apparatus, the message sent over a first channel and comprising an advertisement of at least one second channel for use in sending the data from the first to the second radio apparatus, the advertisement comprising a corresponding proposition/evaluation bit for each second channel, receiving a reply from the second radio apparatus over the first channel, comprising an acceptance of one of the second channels with the corresponding proposition/evaluation bit, a rejection of the second channel and an advertisement of a third channel, or a rejection of the second channel without an advertisement of a third channel, and transmitting the data from the first to the second radio apparatus over an agreed upon second or third channel.

Abstract: A method includes sending a message from a first to at least one second cognitive radio apparatus to determine a channel to be used for sending data from the first to the second radio apparatus, the message sent over a first channel and comprising an advertisement of at least one second channel for use in sending the data from the first to the second radio apparatus, the advertisement comprising a corresponding proposition/evaluation bit for each second channel, receiving a reply from the second radio apparatus over the first channel, comprising an acceptance of one of the second channels with the corresponding proposition/evaluation bit, a rejection of the second channel and an advertisement of a third channel, or a rejection of the second channel without an advertisement of a third channel, and transmitting the data from the first to the second radio apparatus over an agreed upon second or third channel.

Abstract: A method includes sending a message from a first cognitive radio apparatus to at least one second cognitive radio apparatus, the message being sent over a first communication channel and containing an advertisement of at least one second communication channel for use in sending data from the first cognitive radio apparatus to the at least one second cognitive radio apparatus. The method further includes receiving a reply from the at least one second cognitive radio apparatus over the first communication channel, where the reply contains one of an acceptance of one of the at least one second communication channels, a rejection of the at least one second communication channel and an advertisement of at least one third communication channel, or a rejection of the at least one second communication channel without an advertisement of at least one third communication channel.

Abstract: There is provided a method comprising: determining a phase difference between at least two antenna units of a distributed antenna system on the basis of at least one pilot signal received from at least one of a plurality of antenna units; and transmitting phase correction commands to a common base station of the plurality of antenna units on the basis of the determined phase difference in order to synchronize carrier phases between at least two antenna units of the distributed antenna system.

Abstract: There is provided a solution for reusing radio resources opportunistically by private base stations to increase the overall capacity of the network. The solution is based on applying an uplink broadcast in a mobile communication, in which information representing a radio resource allocated by a base station to a user terminal is broadcasted.

Abstract: A solution for optimizing beamforming configurations and transmit power allocation configurations in a telecommunication system comprising a base station and a plurality of user entities is provided. The base station and the user entities are capable of multiple-input multiple-output (MIMO) communications, i.e. capable of communicating through spatial subchannels. The base station calculates iteratively optimal beamforming configurations for the base station and for each user entity and transmit power allocation configurations for each spatial subchannel used in MIMO communications. The base station carries out the calculation on the basis of channel state information received from the user entities by utilizing the information on correlation of different spatial subchannels, i.e. interference between the subchannels, in order to update beamforming configurations and transmit power allocation configurations.

Abstract: A method includes sending a message from a first cognitive radio apparatus to at least one second cognitive radio apparatus, the message being sent over a first communication channel and containing an advertisement of at least one second communication channel for use in sending data from the first cognitive radio apparatus to the at least one second cognitive radio apparatus. The method further includes receiving a reply from the at least one second cognitive radio apparatus over the first communication channel, where the reply contains one of an acceptance of one of the at least one second communication channels, a rejection of the at least one second communication channel and an advertisement of at least one third communication channel, or a rejection of the at least one second communication channel without an advertisement of at least one third communication channel.

Abstract: There is provided a method comprising: determining a phase difference between at least two antenna units of a distributed antenna system on the basis of at least one pilot signal received from at least one of a plurality of antenna units; and transmitting phase correction commands to a common base station of the plurality of antenna units on the basis of the determined phase difference in order to synchronize carrier phases between at least two antenna units of the distributed antenna system.

Abstract: The invention is related to a data loading method in a communication system where sub-carriers include eigenmodes, comprising, for instance: arranging eigenmodes into a predetermined number of clusters, each cluster comprising eigenmodes of different quality levels; pre-allocating transmission power to the eigenmodes with the aid of the calculated required power for achieving the approximated signal-to-noise ratio; determining collective transmission power to be allocated to each cluster based on the pre-allocation; allocating collective transmission power to the eigenmodes.

Abstract: A solution for optimizing beamforming configurations and transmit power allocation configurations in a telecommunication system comprising a base station and a plurality of user entities is provided. The base station and the user entities are capable of multiple-input multiple-output (MIMO) communications, i.e. capable of communicating through spatial subchannels. The base station calculates iteratively optimal beamforming configurations for the base station and for each user entity and transmit power allocation configurations for each spatial subchannel used in MIMO communications. The base station carries out the calculation on the basis of channel state information received from the user entities by utilizing the information on correlation of different spatial subchannels, i.e. interference between the subchannels, in order to update beamforming configurations and transmit power allocation configurations.

Abstract: The invention is related to a data loading method in a communication system where sub-carriers include eigenmodes, comprising, for instance: arranging eigenmodes into a predetermined number of clusters, each cluster comprising eigenmodes of different quality levels; pre-allocating transmission power to the eigenmodes with the aid of the calculated required power for achieving the approximated signal-to-noise ratio; determining collective transmission power to be allocated to each cluster based on the pre-allocation; allocating collective transmission power to the eigenmodes.

Abstract: The invention relates to a receiver and method for improving synchronisation. In the solution of the invention, a signal is received and filtered by a matched filter (500) or processed by a correlator (520). Two or more consecutive samples in the output of the matched filter or correlator are combined and re-sampled in such a manner that the re-sampling is done over as many samples as the combination, and one or more correlation peaks are found in the combined samples.

Abstract: A receiver comprising a digital code tracking loop which receives an input of real and imaginary components of a received signal and in which these components are processed in different branches which each comprise a multiplier (12a-12d) and a filter (13a-13d) connected in series. To improve the characteristics of the code tracking loop in the receiver, each branch of the code tracking loop further comprises circuitry (33a-33d) for absolute-valuing the signal, the circuitry (33a-33d) being connected in series after the filters (13a-13d).

Abstract: A receiver and a method for controlling a receiver, the receiver being implemented on the RAKE principle and comprising a number of correlators (30a-30d) which are able to synchronize with a received signal. To effectively utilize the correlators of the receiver, the operation made of the correlators in the receiver is changed dynamically in the method of the invention between the received signal tracking and acquisition modes according to the need.

Abstract: The invention relates to a method and an arrangement for controlling a loop filter of a digital phase lock, the loop filter filtering a difference signal, which comes from a phase comparator at a predetermined bandwidth and is proportional to a phase error. To reduce oscillation in the adjusting method and to eliminate the errors caused by noise, the loop filter is adjusted non-linearly on the basis of the difference signal from the phase comparator in such a manner that the bandwidth of the loop filter changes.