Method and apparatus for concerted signal transmission on multiple antennas
View Patent ↗A communication method is provided for use in a network in which users are allocated respective symbol positions within timeslots for communication to the respective users from a base station. A signal periodically transmitted from at least two antennas of the base station to a user terminal represents coded information. The signal is transmitted within each of a plurality of periodic timeslots. Within each timeslot, each antenna transmits the same coded information only during an assigned symbol position. The symbol positions assigned to the respective antennas are separated in time according to a specified sequential spacing of symbol positions within the timeslot.
1. A communication method for use in a network in which a plurality of user terminals are allocated respective symbol positions within timeslots for communication to at least one of the plurality of user terminals from a base station, comprising:
periodically transmitting, from the base station, a signal representing coded information to the at least one of the plurality of user terminals utilizing at least two antennas belonging to the base station, the signal being transmitted within each of a plurality of periodic timeslots, the plurality of periodic timeslots being determined based on at least a mobility of the plurality of user terminals, each of the at least two antennas transmitting same coded information only during a symbol position assigned to each of the at least two antennas, the assigned symbol positions being separated in time according to a specified sequential spacing of symbol positions within the timeslot.
2. The method of claim 1 , wherein the at least one of the plurality of user terminals is served by the base station, and
the periodically transmitted signal is transmitted on an orthogonal or quasi-orthogonal code designated for communication with a limited set of one or more user terminals including the at least one of the plurality of user terminals.
3. The method of claim 1 , wherein the specified sequential spacing of symbol positions is characterized by a fixed offset between said symbol positions.
4. The method of claim 1 , wherein the specified sequential spacing of symbol positions is characterized by a programmable offset between said symbol positions.
5. The method of claim 4 , wherein a value of the programmable offset is signaled explicitly.
6. The method of claim 4 , further comprising:
computing a value of the programmable offset from received information.
7. The method of claim 1 , further comprising:
receiving an on/off indicator for antenna diversity, and
performing the periodic transmitting in response to a determination that a value of “on” for the antenna diversity has been indicated.
8. The method of claim 1 , wherein the signal is transmitted within each timeslot in a contiguous sequence of periodic timeslots.
9. The method of claim 1 , wherein the signal is transmitted within each timeslot in a periodic but non-contiguous sequence of timeslots.
10. The method of claim 9 , wherein the periodic but non-contiguous sequence of timeslots including a period of k contiguous timeslots, wherein k is an integer with a value of at least 2.
11. The method of claim 1 , wherein:
a number of antennas is an integer n with a value of at least 2;
a number of sequentially spaced symbol positions within each timeslot is at least 2 and at most n; and
a total of two or more signals containing different coded information are transmitted in each timeslot, each said signal being repeated from each of the at least two antennas according to the specified sequential spacing of symbol positions within the timeslot.
12. The method of claim 11 , in which the two or more signals are transmitted in accordance with a space-time block code.
13. The method of claim 1 , wherein the coded information is a Transmission Power Control (TPC) command.
14. A communication method for use in a network in which a plurality of user terminals are allocated respective symbol positions within timeslots for communication to at least one of the plurality of user terminals from a base station, comprising:
periodically receiving, at the at least one of the plurality of user terminals, a plurality of signals from at least two antennas belonging to the same base station, at least one of the plurality of signals containing same coded information being received from each of the at least two antennas only during a corresponding symbol position within each of a plurality of periodic timeslots, the plurality of periodic timeslots being determined based on at least a mobility of the plurality of user terminals; and
recovering signal values, at the at least one of the plurality of user terminals, using a knowledge of a specified sequential spacing of symbol positions within each of the plurality of periodic timeslot, according to which the symbol positions corresponding to each of the at least two antennas are separated in time.
15. The method of claim 14 , wherein the recovering is carried out in a receiver configured for receiving space-time block codes.
16. The method of claim 14 , wherein the signal values are recovered using a diversity receiver.
17. The method of claim 14 , wherein the recovered signal values are Transmission Power Control (TPC) commands.
18. The method of claim 14 , wherein the recovering signal values further comprises:
despreading the plurality of signals from an orthogonal or quasi-orthogonal code.
19. The method of claim 14 , wherein the signal values are recovered within each of a contiguous sequence of periodic timeslots.
20. The method of claim 14 , wherein the signal values are recovered within each of a periodic but non-contiguous sequence of timeslots.
21. A communication method for use in a network in which a plurality of user terminals are allocated respective symbol positions within timeslots for communication to at least one of the plurality of user terminals from a base station, comprising:
periodically transmitting, from the base station, a signal representing coded information to the at least one of the plurality of user terminals utilizing at least two antennas belonging to the base station, the signal being transmitted within each of a plurality of periodic but non-contiguous sequence of timeslots, each of the at least two antennas transmitting same coded information only during an assigned symbol position of each of the at least two antennas, the assigned symbol positions of the at least two antennas being separated in time according to a specified sequential spacing of symbol positions within the timeslot, the periodic but non-contiguous sequence of timeslots including a period of k contiguous timeslots with k being an integer with a value of at least 2.
22. A communication method for use in a network in which a plurality of user terminals are allocated respective symbol positions within timeslots for communication to at least one of the plurality of user terminals from a base station, comprising:
periodically receiving, at the at least one of the plurality of user terminals, a plurality of signals from at least two antennas belonging to the same base station, at least one of the plurality of signals containing same coded information being received from each of the at least two antennas only during a corresponding symbol position within each of a plurality of periodic but non-contiguous timeslots; and
recovering signal values, at the at least one of the plurality of user terminals, using a knowledge of a specified sequential spacing of symbol positions within each of the plurality of periodic but non-contiguous timeslots, according to which the symbol positions corresponding to each of the at least two antennas are separated in time, the periodic but non-contiguous sequence of timeslots including a period of k contiguous timeslots with k being an integer with a value of at least 2.