Methods and apparatus of providing transmit and/or receive diversity with multiple antennas in wireless communication systems

A method of operating a wireless terminal to communicate with a base station, said wireless terminal including a single transmitter signal processing chain including a dwell boundary switching module for coupling said single transmitter chain to a plurality of antenna elements, said dwell boundary switching module for switching on dwell boundaries but not in between, said plurality of antenna elements including at least a first antenna element and a second antenna element each of which can be used independently, the method comprising:

• operating the dwell boundary switching module during a first period of time to switch between said first and second antenna elements on at least some dwell boundaries which occur during said first period of time to thereby change the antenna element used to transmit signals from said single transmitter signal processing chain, a dwell being a second period of time within said first period of time during which said wireless terminal uses a single set of tones to transmit signals to said base station, a different set of tones being used in immediately consecutive dwells during said first period of time, said dwell boundary switching module switching between said first and second antenna elements as a function of a signal from said base station indicative of channel quality;
• and
• wherein said signal indicative of channel quality is a transmission acknowledgement signal indicating success or failure in receipt of a transmitted signal.

A method of operating a wireless terminal to communicate with a base station, said wireless terminal including a single transmitter signal processing chain including a dwell boundary switching module for coupling said single transmitter chain to a plurality of antenna elements, said dwell boundary switching module for switching on dwell boundaries but not in between, said plurality of antenna elements including at least a first antenna element and a second antenna element each of which can be used independently, the method comprising:

• operating the dwell boundary switching module during a first period of time to switch between said first and second antenna elements on at least some dwell boundaries which occur during said first period of time to thereby change the antenna element used to transmit signals from said single transmitter signal processing chain, a dwell being a second period of time within said first period of time during which said wireless terminal uses a single set of tones to transmit signals to said base station, a different set of tones being used in immediately consecutive dwells during said first period of time, said dwell boundary switching module switching between said first and second antenna elements as a function of a signal from said base station indicative of channel quality, said switching is performed as a function of multiple signals received from said base station;
• and
• maintaining different sets of switching control information for signals received from said base station corresponding to signals transmitted from said WT using different antenna elements.

A method of operating a wireless terminal to communicate with a base station, said wireless terminal including a single transmitter processing chain including a channel estimation boundary switching module for coupling said transmitter processing chain to a plurality of antenna elements, said channel estimation boundary switching module switching on signal boundaries corresponding to base station channel estimation signal boundaries but not in between, a base station channel estimation switching boundary being a signal point where said base station transitions between channel estimation intervals, the channel estimation performed by a base station in one channel estimation interval being independent of the channel estimation performed in the immediately preceding channel estimation interval, said plurality of antenna elements including at least a first antenna element and a second antenna element each of which can be used independently, the method comprising:

• operating the channel estimation boundary switching module during a first period of time to switch between said first and second antenna elements on at least some channel estimation boundaries which occur during said first period of time to thereby change the antenna element used to transmit signals from said single transmitter signal processing chain;
• wherein said channel estimation boundary switching module switches between said first and second antenna elements as a function of a signal from said base station indicative of channel quality;
• and
• wherein said signal indicative of channel quality is a transmission acknowledgement signal indicating success or failure in receipt of a transmitted signal.

A method of operating a wireless terminal to communicate with a base station, said wireless terminal including a single transmitter processing chain including a channel estimation boundary switching module for coupling said transmitter processing chain to a plurality of antenna elements, said channel estimation boundary switching module switching on signal boundaries corresponding to base station channel estimation signal boundaries but not in between, a base station channel estimation switching boundary being a signal point where said base station transitions between channel estimation intervals, the channel estimation performed by a base station in one channel estimation interval being independent of the channel estimation performed in the immediately preceding channel estimation interval, said plurality of antenna elements including at least a first antenna element and a second antenna element each of which can be used independently, the method comprising:

• operating the channel estimation boundary switching module during a first period of time to switch between said first and second antenna elements on at least some channel estimation boundaries which occur during said first period of time to thereby change the antenna element used to transmit signals from said single transmitter signal processing chain;
• wherein said channel estimation boundary switching module switches between said first and second antenna elements as a function of a signal from said base station indicative of channel quality;
• and
• wherein said switching is performed as a function of multiple signals received from said base station, the method includes:
• maintaining different sets of switching control information for signals received from said base station corresponding to signals transmitted from said WT using different antenna elements.

A wireless terminal for use in a communications system including a base station, said wireless terminal the comprising:

• a single transmitter processing chain including a switching module for coupling said transmitter processing chain to a plurality of antenna elements, said switching module switching on signal boundaries corresponding to base station channel estimation reset points but not in between, a base station channel estimation reset point being a signal point where said base station transitions between channel estimation intervals and resets a channel estimate included in the base station, the channel estimation performed by a base station in a channel estimation interval immediately preceding a channel reset being independent of the channel estimation performed in a subsequent channel estimation interval immediately following the channel estimate reset, said plurality of antenna elements including at least a first antenna element and a second antenna element each of which can be used independently;
• and
• means for controlling the switching module during a first period of time to switch between said first and second antenna elements on at least some signal boundaries corresponding to base station channel estimate reset points which occur during said first period of time to thereby change the antenna element used to transmit signals from said single transmitter signal processing chain.

A method of operating an OFDM communications device, the method comprising:

• i) assigning tones in a first set of tones to a plurality of different tone subsets including at least a first and a second tone subset, each of said different tone subsets being different from one another by at least one tone;
• ii) transmitting each of said different tone subsets in parallel during the same rime interval using a different antenna element;
• and
• iii) repeating steps i) and ii).

An OFDM communications device, the device comprising:

• means for assigning tones in a first set of tones to a plurality of different tone subsets including at least a first and a second tone subset, each of said different tone subsets being different from one another by at least one tone;
• means for transmitting each of said different tone subsets in parallel during the same time interval using a different antenna element;
• and
• control means for controlling said assigning and transmitting means to repeat the operations of assigning and transmitting.