Wireless transmission system and wireless transmission method and wireless station and transmitting station for use therein

A transmitting station for use in a wireless transmission system for transmitting a signal to a receiving station via a plurality of wireless stations capable of signal transmission, wherein a path diversity system is formed by at least one of the wireless stations that is capable of signal transmission, a multi-path channel and the receiving station, the transmitting station comprising:

• a delay amount selecting section for selecting, from among a plurality of predetermined delay amounts, a predetermined delay amount to be given to signals to be transmitted to each of the wireless stations;
• a transmission timing control section for determining a transmission start timing at which to start the transmission of the signals from the wireless stations, the transmission of the signals being a timing obtained by delaying a reference timing for transmission of the signals by the predetermined delay amount selected by said delay amount selecting section;
• and
• a transmitting section for transmitting the signals to each of the wireless stations at the transmission start timing,
• wherein the predetermined delay amount is determined so that:
• 1) the signals are received by the receiver side at a plurality of signal-receiving timings;
• 2) a number of signal-receiving timings is less than or equal to a predetermined maximum number of effective branches;
• 3) a difference between the plurality of signal-receiving timings is greater than or equal to a predetermined delay resolution;
• and 4) a difference between a maximum value and a minimum value of the signal-receiving timings is less than or equal to a predetermined maximum delay, and
• when the number of wireless stations transmitting the signals is larger than the predetermined maximum number of effective branches, the number of signal-receiving timings at which the receiving station receives signals is made equal to the predetermined maximum number of effective branches.

A method for use in a wireless transmission system that includes a plurality of wireless stations, each wireless station is capable of signal transmission to a receiving station, wherein a path diversity system is formed by at least one of the wireless stations, a multipath channel and the receiving station, the method comprising:

• determining a transmission start timing at which to start transmission of signals from the wireless stations, the transmission start timing being a timing obtained by delaying a reference timing for the transmission of the signals by a predetermined delay amount;
• transmitting the signals at the transmission start timing determined;
• and
• receiving the transmitted signals at the receiving station,
• wherein the predetermined delay amount is determined so that:
• 1) the signals are received at the receiving station at a plurality of signal-receiving timings;
• 2) a number of signal-receiving timings is less than or equal to a predetermined maximum number of effective branches;
• 3) a difference between the plurality of signal-receiving timings is greater than or equal to a predetermined delay resolution;
• and 4) a difference between a maximum value and a minimum value of the plurality of signal-receiving timings is less than or equal to a predetermined maximum delay, and
• when the number of wireless stations transmitting the signals is larger than the predetermined maximum number of effective branches, the number of signal-receiving timings at which the receiving station receives signals is made equal to the predetermined maximum number of effective branches.

A method for use in a wireless transmission including a plurality of wireless stations wherein each wireless station is capable of signal transmission to a receiving station, wherein a path diversity system is formed by at least one of the wireless stations, a multipath channel and the receiving station, the method comprising:

• determining a transmission start timing at which to start the transmission of signals from the wireless stations, the transmission start timing being a timing obtained by delaying a reference timing for the transmission of the signals by a predetermined delay amount;
• and
• transmitting the signals at the transmission start timing determined,
• wherein the predetermined delay amount is determined so that:
• 1) the signals are received by the receiver side at a plurality of signal-receiving timings;
• 2) a number of signal-receiving timings is less than or equal to a predetermined maximum number of effective branches;
• 3) a difference between the plurality of signal-receiving timings is greater than or equal to a predetermined delay resolution;
• and 4) a difference between a maximum value and a minimum value of the plurality of signal-receiving timings is less than or equal to a predetermined maximum delay, and
• when the number of wireless stations transmitting the signals is larger than the predetermined maximum number of effective branches, the number of signal-receiving timings at which the receiving station receives signals is made equal to the predetermined maximum number of effective branches.

A method for transmitting a signal from a transmitting station to a receiving station via a plurality of wireless stations capable of signal transmission, wherein a path diversity system is formed by at least one of the wireless stations that is capable of signal transmission, a multi-path channel and the receiving station, the method comprising:

• selecting, from among a plurality of predetermined delay amounts, a predetermined delay amount to be given to signals to be transmitted to each of the wireless stations;
• determining a transmission start timing at which to start the transmission of a signal, the transmission start timing being a timing obtained by delaying a reference timing for the transmission of the signals by the predetermined delay amount selected;
• and
• transmitting the signals to each of the wireless stations at the transmission start timing,
• wherein the predetermined delay amount is determined so that:
• 1) the signals are received by the receiver side at a plurality of signal-receiving timings;
• 2) a number of signal-receiving timings is less than or equal to a predetermined maximum number of effective branches;
• 3) a difference between the plurality of signal-receiving timings is greater than or equal to a predetermined delay resolution;
• and 4) a difference between a maximum value and a minimum value of the plurality of signal-receiving timings is less than or equal to a predetermined maximum delay, and
• when the number of wireless stations transmitting the signals is larger than the predetermined maximum number of effective branches, the number of signal-receiving timings at which the receiving station receives signals is made equal to the predetermined maximum number of effective branches.