Methods and apparatus of providing transmit diversity in a multiple access wireless communication system
First Claim
1. A method for providing channel diversity in a multiple access wireless communication system, the method comprising:
- transmitting a plurality of signals using a plurality of communication channels, wherein each of the plurality of communication channels has a physical characteristic that is detectable by a wireless terminal and each of the plurality of signals has a signal transmission characteristic;
changing at least one signal transmission characteristic to modify the physical characteristic of at least one of the plurality of communication channels as received by the wireless terminal;
receiving a feedback information from the wireless terminal wherein the feedback information is based on the modified physical characteristic; and
selecting one of the plurality of communication channels based on the feedback information for use in transmission,wherein the changing at least one signal transmission characteristic is performed periodically with a periodicity that is longer than or equal to a duration between receiving two feedback information.
3 Assignments
0 Petitions
Accused Products
Abstract
Methods and apparatus for providing channel diversity to wireless terminals (WTs) in a manner that reduces the latency between the time a WT encounters satisfactory channel conditions are described. A plurality of communications channels with different physical characteristics are maintained in a cell by a base station (BS). Each WT monitors multiple channels and maintains multiple channel estimates at the same time so that rapid switching between channels is possible. Channel quality information is conveyed from each WT to the BS. The WT or BS selects a channel based on the measured channel quality. By supporting multiple channels and by introducing periodic variations into the channels in various embodiments, the time before a WT encounters a channel with good or acceptable channel conditions is minimized even if the WT does not change location. Multiple antennas are used at the BS to support numerous channels simultaneously, e.g., by controlling antenna patterns.
20 Citations
32 Claims
-
1. A method for providing channel diversity in a multiple access wireless communication system, the method comprising:
-
transmitting a plurality of signals using a plurality of communication channels, wherein each of the plurality of communication channels has a physical characteristic that is detectable by a wireless terminal and each of the plurality of signals has a signal transmission characteristic; changing at least one signal transmission characteristic to modify the physical characteristic of at least one of the plurality of communication channels as received by the wireless terminal; receiving a feedback information from the wireless terminal wherein the feedback information is based on the modified physical characteristic; and selecting one of the plurality of communication channels based on the feedback information for use in transmission, wherein the changing at least one signal transmission characteristic is performed periodically with a periodicity that is longer than or equal to a duration between receiving two feedback information. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A method for facilitating channel diversity in a multiple access wireless communication system, the method comprising:
-
receiving a plurality of signals from a plurality of communication channels having at least one physical characteristic modified by at least one signal transmission characteristic of the plurality of signals; measuring channel quality information based on the at least one physical characteristic of the plurality of communication channels, wherein the channel quality information comprises at least one of a signal-to-noise ratio (SNR) or a signal-to-interference ratio (SIR) relating to at least one of the plurality of communication channels; and transmitting the channel quality information to a base station, wherein the channel quality information is used to select one of the plurality of communication channels for use in transmission, wherein the channel quality information is transmitted periodically with a periodicity that is longer than or equal to a duration between receiving two feedback information.
-
-
11. An apparatus for providing channel diversity in a multiple access wireless communication system, the apparatus comprising:
-
means for transmitting a plurality of signals using a plurality of communication channels, wherein each of the plurality of communication channels has a physical characteristic that is detectable by a wireless terminal and each of the plurality of signals has a signal transmission characteristic; means for changing at least one signal transmission characteristic to modify the physical characteristic of at least one of the plurality of communication channels as received by the wireless terminal; means for receiving a feedback information from the wireless terminal wherein the feedback information is based on the modified physical characteristic; and means for selecting one of the plurality of communication channels based on the feedback information for use in transmission, wherein the means for changing changes the at least one signal transmission periodically with a periodicity that is longer than or equal to a duration between receiving two feedback information. - View Dependent Claims (12, 13, 14, 15, 16, 17, 18, 19)
-
-
20. An apparatus for facilitating channel diversity in a multiple access wireless communication system, the apparatus comprising:
-
means for receiving a plurality of signals from a plurality of communication channels having at least one physical characteristic modified by at least one signal transmission characteristic of the plurality of signals; means for measuring channel quality information based on the at least one physical characteristic of the plurality of communication channels, wherein the channel quality information comprises at least one of a signal-to-noise ratio (SNR) or a signal-to-interference ratio (SIR) relating to at least one of the plurality of communication channels; and means for transmitting the channel quality information to a base station, wherein the channel quality information is used to select one of the plurality of communication channels for use in transmission, wherein the channel quality information is transmitted periodically with a periodicity that is longer than or equal to a duration between receiving two feedback information.
-
-
21. A base station for providing channel diversity in a multiple access wireless communication system, the base station comprising:
-
a transmitter for transmitting a plurality of signals using a plurality of communication channels, wherein each of the plurality of communication channels has a physical characteristic that is detectable by a wireless terminal and each of the plurality of signals has a signal transmission characteristic; a processor coupled to the transmitter for changing at least one signal transmission characteristic to modify the physical characteristic of at least one of the plurality of communication channels as received by the wireless terminal; and a receiver coupled to the processor for receiving feedback information from the wireless terminal wherein the feedback information is based on the modified physical characteristic; and wherein the processor selects one of the plurality of communication channels based on the feedback information for use in transmission, wherein the processor changes at least one signal transmission characteristic periodically with a periodicity that is longer than or equal to a duration between receiving two feedback information. - View Dependent Claims (22, 23, 24, 25, 26, 27, 28, 29)
-
-
30. A mobile terminal for facilitating channel diversity in a multiple access wireless communication system, the mobile terminal comprising:
-
a receiver for receiving a plurality of signals from a plurality of communication channels having at least one physical characteristic modified by at least one signal transmission characteristic of the plurality of signals; a processor coupled to the receiver for measuring channel quality information based on the at least one physical characteristic of the plurality of communication channels, wherein the channel quality information comprises at least one of a signal-to-noise ratio (SNR) or a signal-to-interference ratio (SIR) relating to at least one of the plurality of communication channels; and a transmitter for transmitting the channel quality information to a base station, wherein the channel quality information is used to select one of the plurality of communication channels for use in transmission, wherein the channel quality information is transmitted periodically with a periodicity that is longer than or equal to a duration between receiving two feedback information.
-
-
31. A non-transitory computer-readable medium storing a computer program, wherein execution of the computer program is for:
-
transmitting a plurality of signals using a plurality of communication channels, wherein each of the plurality of communication channels has a physical characteristic that is detectable by a wireless terminal and each of the plurality of signals has a signal transmission characteristic; changing at least one signal transmission characteristic to modify the physical characteristic of at least one of the plurality of communication channels as received by the wireless terminal; receiving a feedback information from the wireless terminal wherein the feedback information is based on the modified physical characteristic; and selecting one of the plurality of communication channels based on the feedback information for use in transmission, wherein the changing at least one signal transmission characteristic is performed periodically with a periodicity that is longer than or equal to a duration between receiving two feedback information.
-
-
32. A non-transitory computer-readable medium storing a computer program, wherein execution of the computer program is for:
-
receiving a plurality of signals from a plurality of communication channels having at least one physical characteristic modified by at least one signal transmission characteristic of the plurality of signals; measuring channel quality information based on the at least one physical characteristic of the plurality of communication channels, wherein the channel quality information comprises at least one of a signal-to-noise ratio (SNR) or a signal-to-interference ratio (SIR) relating to at least one of the plurality of communication channels; and transmitting the channel quality information to a base station, wherein the channel quality information is used to select one of the plurality of communication channels for use in transmission, wherein the channel quality information is transmitted periodically with a periodicity that is longer than or equal to a duration between receiving two feedback information.
-
Specification