Transmission method and related base station
The invention relates to transmission from a base station to a receiver, the base station comprising first radiating means arranged for transmitting according to an antenna pattern with respect to the receiver and further comprising second radiating means arranged for transmitting according to the same antenna pattern as the first radiating means with respect to the receiver, the transmissions of the first and second radiating means being time shifted by a determined duration.
1. A method of receiving from a base station by a first device, the method comprising:
the first device receiving a first signal from a first antenna assembly of the base station;
the first device receiving a second signal from a second antenna assembly of the base station, wherein the second signal was transmitted by the second antenna assembly by transmitting the first signal time shifted by a delay of known duration, wherein the delay of known duration is set so that a correlation factor between transmissions of the first and second signals is below a predetermined level; and
the first device decoding the first and second signals.
2. The method of claim 1 , wherein the first device comprises a mobile terminal.
3. The method of claim 1 , wherein:
the first signal is transmitted from the first antenna assembly according to a first antenna pattern; and
the second signal is transmitted from the second antenna assembly according to substantially the same first antenna pattern.
4. The method of claim 1 , wherein the first device comprises a mobile terminal in motion, wherein the first signal is transmitted according to an antenna pattern adapted to follow the motion of the mobile terminal, and wherein the second signal is transmitted according to substantially the same antenna pattern adapted to follow the motion of the mobile terminal.
5. The method of claim 1 , wherein the delay of known duration is set by:
analyzing at least one impulse response of at least one channel between one of the first and second antenna assemblies and the first device;
setting the delay of known duration based on the at least one impulse response of the at least one channel to set the correlation factor below the predetermined threshold.
6. The method of claim 5 , wherein the delay of known duration is set by:
analyzing impulse responses successively over time to establish a distribution of impulse responses; and
setting the delay of known duration based on the distribution of impulse responses.
7. The method of claim 1 , wherein the delay of known duration is set so that inter-symbol interference between the first signal and the second signal is below a predetermined threshold at the first device.
8. The method of claim 1 , wherein:
the first signal is transmitted from the first antenna assembly at a first power; and
the second signal is transmitted from the second antenna assembly at a second power different from the first power.
9. The method of claim 8 , wherein the first power for transmission from the first antenna assembly and the second power for transmission from the second antenna assembly are set in response to the power of a signal received at the first antenna assembly relative to the power of the signal received at the second antenna assembly.
10. A first device, comprising:
one or more antennas for performing wireless communication with a base station; and
processing hardware coupled to the one or more antennas;
wherein the processing hardware and one or more antennas are configured to:
receive a first signal from a first antenna assembly of the base station;
receive a second signal from a second antenna assembly of the base station, wherein the second signal was transmitted by the second antenna assembly by transmitting the first signal time shifted by a delay of known duration, wherein the delay of known duration is set so that a correlation factor between transmissions of the first and second signals is below a predetermined level; and
decode the first and second signals.
11. The first device of claim 10 , wherein the first device comprises a mobile terminal.
12. The first device of claim 10 , wherein:
the first signal is transmitted from the first antenna assembly according to a first antenna pattern; and
the second signal is transmitted from the second antenna assembly according to substantially the same first antenna pattern.
13. The first device of claim 10 , wherein the first device comprises a mobile terminal in motion, wherein the first signal is transmitted according to an antenna pattern adapted to follow the motion of the mobile terminal, and wherein the second signal is transmitted according to substantially the same antenna pattern adapted to follow the motion of the mobile terminal.
14. The first device of claim 10 , wherein the delay of known duration is based on analyzing at least one impulse response of at least one channel between one of the first and second antenna assemblies and the first device to set the correlation factor below the predetermined threshold
15. The first device of claim 14 , wherein the delay of known duration based on the distribution of impulse responses generated from analyzing impulse responses successively over time.
16. The first device of claim 10 , wherein the delay of known duration is set so that inter-symbol interference between the first signal and the second signal is below a predetermined threshold at the first device.
17. The first device of claim 10 , wherein:
the first signal is transmitted from the first antenna assembly at a first power; and
the second signal is transmitted from the second antenna assembly at a second power different from the first power.
18. The first device of claim 17 , wherein the first power for transmission from the first antenna assembly and the second power for transmission from the second antenna assembly are set in response to the power of a signal received at the first antenna assembly relative to the power of the signal received at the second antenna assembly.