Method for transmitting pilot channels and a cellular radio system

A cellular radio system comprising:

• in each cell, at least one base station configured to communicate with mobile stations located within its coverage area, the communication including (i) transmitting information about said system to said mobile stations using control channels, and (ii) transmitting at least one data signal to said mobile stations using radiation patterns that change in time,
• wherein said at least one base station is configured to transmit at least one first pilot signal to all mobile stations within the cell, said pilot signal having a predetermined radiation pattern, said predetermined radiation pattern defining the coverage area for said cell,
• wherein said at least one base station is configured to transmit a second pilot signal in said transmission directions that change in time and said second pilot signal being incapable of carrying control information, and
• wherein said at least one data signal and said second pilot signal are transmitted using matching radiation patterns.

A cellular radio system comprising:

• in each cell, at least one base station configured to communicate with mobile stations located within its coverage area, the communication including (i) transmitting information about said system to said mobile stations using control channels, and (ii) transmitting at least one data signal to said mobile stations using transmission directions that change in time,
• wherein said at least one base station is configured to transmit at least one first pilot signal to all mobile stations within the cell, said pilot signal having a predetermined radiation pattern, said predetermined radiation pattern defining the coverage area for said cell,
• wherein said at least one base station is configured to transmit a second pilot signal in said transmission directions that change in time, said at least one data signal and said second pilot signal are transmitted using matching radiation patterns, and said second pilot signal is incapable of carrying control information, and
• wherein said base station comprises:
• at least one antenna group, said antenna group including a plurality of antennas,
• a group of radio-frequency units connected to said antenna group,
• at least one channel unit, an input of said channel unit being configured to receive signals from said radio-frequency units, said channel unit comprising a phaser configured to phase said at least one data signal to be transmitted and received with said antenna group so that a gain obtained from said antenna group is largest in a desired direction,
• a control unit configured to control said channel unit,
• a separator configured to separate data containing connection quality information from the signals received by each mobile station, and
• a baseband unit connected to the output of said channel unit, said channel unit further comprising:
• a searcher configured to search for incoming directions and delays of best signal components received from said mobile stations, and
• a controller configured to control formation of radiation patterns used when transmitting said at least one data signal from said base station to said mobile station based on a power measurement of said at least one data signal and said connection quality information received from said mobile station.

A cellular radio system comprising:

• in each cell, at least one base station configured to communicate with mobile stations located within its coverage area, the communication including (i) transmitting information about said system to said mobile stations using control channels, and (ii) transmitting at least one data signal to said mobile stations using transmission directions that change in time,
• wherein said at least one base station transmits at least one first pilot signal to all mobile stations within the cell, said pilot signal having a predetermined radiation pattern, said predetermined radiation pattern defining the coverage area for said cell,
• wherein said at least one base station is configured to transmit a second pilot signal in said transmission directions that change in time and said second pilot signal is incapable of carrying control information,
• wherein said at least one data signal and said second pilot signal are transmitted using matching radiation patterns, and
• wherein said base station comprises:
• at least one antenna group, said antenna group including a plurality of antennas,
• an analog phaser connected to said antenna group and configured to phase received signals so that a gain obtained from said antenna group is largest in desired beam-like directions,
• a group of radio-frequency units, each said radio-frequency unit having an input and an output wherein said input of said radio-frequency units is configured to receive said phased signals,
• a digitizer connected to said output of said radio-frequency units and configured to digitize said output of said radio-frequency units,
• at least one channel unit, an input of said channel unit being configured to receive digitized signals output from said digitizer, said channel unit comprising at least one measurer and switcher, the measurer and the switcher being configured to (i) search said digitized signals for antenna beams corresponding to incoming directions of a strongest signal component and (ii) measure delays of signal components, and
• a controller configured to control said phaser so that said largest gain of signals to be transmitted is set in said desired direction.

A method for transmitting pilot channels in a cellular radio network, having in each cell, at least one base station configured to communicate with mobile stations located within a respective area, the communication including (i) transmitting at least one data signal in a downlink direction, and (ii) transmitting system information to respective said mobile stations on control channels, said method comprising:

• said at least one base station transmitting at least one first pilot signal to all mobile stations within the cell, said pilot signal having a predetermined radiation pattern, the predetermined radiation pattern defining a coverage area for said cell;
• and
• said at least one base station transmitting a second pilot signal specific for at least one said mobile station located within said coverage area, using an antenna radiation pattern based on at least one signal received by said base station as a result of transmitting by said at least one mobile station,
• wherein said at least one data signal and said second pilot signal are transmitted using matching radiation patterns and said second pilot signal being incapable of carrying control information.

A cellular radio system comprising:

• in each cell, at least one base station configured to communicate with mobile stations located within its coverage area, the communicating including (i) transmitting information about said system to said mobile stations using control channels, and (ii) transmitting at least one data signal to said mobile stations using transmission directions that change in time,
• wherein said at least one base station is configured to transmit at least one first pilot signal to all mobile stations within the cell, said pilot signal having a predetermined radiation pattern, said predetermined radiation pattern defining the coverage area for said cell,
• wherein said at least one base station is configured to transmit a second pilot signal in said transmission directions that change in time and said second pilot signal is incapable of carrying control information,
• wherein said at least one data signal and said second pilot signal are transmitted using matching radiation patterns and
• wherein said base station comprises:
• at least one antenna group, said antenna group comprising a plurality of antennas,
• a group of radio-frequency units each said radio-frequency unit having an input and an output, wherein said input of said radio-frequency units is configured to receive a phased signal,
• a digitizer, connected to said output of said radio-frequency units and configured to digitize said output of said radio-frequency units, and
• at least one channel unit, an input of said channel unit being configured to receive a digitized signal output from said digitizer, said channel unit comprising at least one measurer and switcher, the measurer and switcher being configured to (i) search said digitized signal for antenna beams corresponding to incoming directions of a strongest signal component and (ii) measure delays of said components.

A method for transmitting pilot channels in a cellular radio network, having in each cell, at least one base station configured to communicate with mobile stations located within a respective area, the communication including (i) transmitting at least one data signal in a downlink direction, and (ii) transmitting system information to respective said mobile stations on control channels, said method comprising:

• said at least one base station transmitting at least one first pilot signal to all mobile stations within the cell, said pilot signal having a predetermined radiation pattern, the predetermined radiation pattern defining a coverage area for said cell;
• and
• said at least one base station transmitting an un-modulated common control signal specific for at least one said mobile station located within said coverage area, using an antenna radiation pattern based on at least one signal received by said base station as a result of transmitting by said at least one mobile station,
• wherein said at least one data signal and said un-modulated common control signal are transmitted using matching radiation patterns.