1. An apparatus for evaluating a wireless link between a transmitter and a first receiver in a multiple access wireless communications system, wherein said transmitter is transmitting information intended for a first receiver in a first transmission mode and information intended for a second receiver in a second transmission mode that is different from said first transmission mode, the apparatus comprising:
means for receiving information that is intended for the second receiver and that is transmitted in said second transmission mode;
means for obtaining, at said first receiver, an error measure for said information that is received at said first receiver and intended for said second receiver;
means for determining if said second transmission mode is an acceptable transmission mode at least in part based on said error measure obtained for said information that is received at said first receiver and intended for said second receiver; and
means for determining if said second transmission mode should be used for subsequent transmissions of information frames that is intended for said first receiver only if said second transmission mode is determined to be acceptable, said means for determining if said second transmission mode should be used for subsequent frame transmissions comprising:
means for determining if said second transmission mode is higher than a current transmission mode that is used to transmit information intended for said first receiver;
means for using said second transmission mode for subsequent transmissions, from said transmitter, of information intended for said first receiver if said second transmission mode is determined to be higher than said current transmission mode; and
means for continuing to use said current transmission mode for subsequent transmissions, from said transmitter, of information intended for said first receiver if said second transmission mode is determined to be lower than said current transmission mode.
2. An apparatus as claimed in claim 1, wherein said means for determining if said second transmission mode should be used for subsequent transmissions of information comprises means for comparing a characteristic of said second transmission mode to said first transmission mode.
3. An apparatus as claimed in claim 1, further comprising:
means for indicating to said transmitter that said second transmission mode should be used for subsequent transmissions of frames intended for said first receiver.
4. An apparatus as claimed in claim 3, further comprising:
means for indicating to multiple transmitters that said selected transmission mode should be used for subsequent transmissions of frames intended for said first receiver.
5. An apparatus as claimed in claim 3, further comprising:
means for transmitting subsequent frames to said receiver in said second transmission mode.
6. An apparatus as claimed in claim 1, wherein said means for determining if said second transmission mode is acceptable comprises means for determining if said obtained error measure is above or below an error threshold.
7. An apparatus as claimed in claim 1, further comprising:
means for adding said second transmission mode to a database of acceptable transmission modes if said obtained error measure for said information transmitted in said second transmission mode is below an error threshold.
8. An apparatus as claimed in claim 7, further comprising:
means for selecting a lower transmission mode for information intended for said first receiver from acceptable modes identified in said database.
9. An apparatus as claimed in claim 7, further comprising:
means for ranking transmission modes that are added to said database of acceptable transmission modes.
10. An apparatus as claimed in claim 9, further comprising:
means for selecting a new transmission mode for information intended for said first receiver at least in part based on said transmission mode rankings.
11. An apparatus as claimed in claim 10, further comprising:
means for accumulating error statistics for transmission modes that are added to said database of acceptable transmission modes.
12. An apparatus as claimed in claim 11, further comprising:
means for selecting a new transmission mode for information intended for said first receiver at least in part based on said accumulated error statistics.
13. An apparatus as claimed in claim 7, further comprising:
means for replacing a current transmission mode with the next higher acceptable transmission mode that is stored in said database of acceptable modes.
14. An apparatus as claimed in claim 1, further comprising:
means for projecting an acceptability of other transmission modes that may be used to transmit information intended for said first receiver based at least in part on said mode acceptability determination of said information that is intended for said second receiver and transmitted in said second transmission mode.
15. An apparatus as claimed in claim 1, further comprising:
means for ensuring that said first transmission mode used by said transmitter to transmit information intended for said first receiver is no higher than said second transmission mode if said second transmission mode is not acceptable; and
means for ensuring that said first transmission mode used by said transmitter to transmit information intended for said first receiver is at least as high as said second transmission mode if said second transmission mode is acceptable.
16. An apparatus as claimed in claim 1, further comprising:
means for decoding said information intended for said second receiver into decoded information before said error measure is obtained, said error measure being related to said decoded information.
17. An apparatus as claimed in claim 16, wherein means for obtaining said error measure comprises means for utilizing information selected from the group comprising the metric of a winning path in a Virterbi decoder, the output bitsymbolpacket likelihood, a cyclic redundancy check code, a parity check code, a Reed-Solomon code, a BCH code, a Hamming code, a cyclic code, an arithmetic code, or a Golay code, or combinations thereof.
18. An apparatus as claimed in claim 1, wherein said error measure for said information is obtained prior to decoding.
19. An apparatus as claimed in claim 18, wherein said means for obtaining an error measure comprises means for utilizing information selected from the group comprising the means square error of equalizer, a measure of equalizer convergence, or post-processing signal to noise plus interference ratio, or combinations thereof.
20. An apparatus as claimed in claim 1, wherein said transmitter transmits said information from multiple antennas.
21. An apparatus as claimed in claim 1, wherein said multiple access wireless communications system utilizes a multiple access protocol that is selected from at least one of a group of multiple access protocols comprising: time-division multiple access (TDMA), frequency-division multiple access (FDMA), code-division multiple access (CDMA), space-division multiple access (SDMA), orthogonal frequency division multiple access (OFDMA), wavelength division multiple access (WDMA), wavelet division multiple access, orthogonal division multiple access (ODMA), quasi-ODMA, packet reservation multiple access (PRMA), or carrier sense multiple access (CSMA), or combinations thereof.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method using multiple sampling frequencies, applied to a touch device, comprising:
determining which of first and second sampling frequencies is provided to a receiver for use in sampling touch inputs of a user from a touch panel of the touch device; and
sampling the touch inputs from the touch panel in first and second successive time frames using first and second different sampling frequencies, respectively.
2. The method of claim 1, further comprising:
detecting noise that interferes with the first sampling frequency used in the first time frame;
while continuing to sample touch inputs from the touch panel using only the second sampling frequency, changing the first sampling frequency to a first candidate sampling frequency that is not interfered with by the detected noise; and
sampling touch inputs from the touch panel in the first and second successive time frames using the first candidate and second sampling frequencies, respectively.
3. The method of claim 2, wherein the step of changing the first sampling frequency to the first candidate sampling frequency comprises:
iteratively adjusting the first sampling frequency by a predetermined amount to an adjusted frequency; and
determining at each iteration if noise interferes with the adjusted frequency.
4. The method of claim 2, further comprising:
after a period of time, changing the first candidate frequency back to the first frequency; and
sampling the touch inputs from the touch panel in the first and second successive time frames using the first and second sampling frequencies, respectively.
5. The method of claim 2, further comprising:
detecting noise that interferes with the second sampling frequency;
while continuing to sample touch inputs from the touch panel using only the first candidate sampling frequency, changing the second sampling frequency to a second candidate sampling frequency that is not interfered with by the detected noise; and
sampling touch inputs from the touch panel in the first and second successive time frames using the first candidate and second candidate sampling frequencies, respectively.
6. The method of claim 1, further comprising:
controlling a clock switch with a microcontroller unit (MCU) to switch between the first and second sampling frequencies.
7. The method claim 1, further comprising:
controlling first and second voltage controllable oscillators to generate the first and second different sampling frequencies.
8. The method of claim 1, further comprising:
sampling touch inputs from the touch panel in first, second, and third successive time frames using first, second, and third different sampling frequencies, respectively.
9. A touch device using multiple sampling frequencies, comprising:
a touch panel, configured to receive a touch input of a user;
a control circuit, comprising:
a driver;
a receiver, configured to sample the touch inputs;
a sampling frequency generation circuit, connected to the receiver, configured to generate first and second sampling frequencies in first and second successive time frames, respectively; and
a microcontroller (MCU), configured to determine which of the first and second sampling frequencies is provided to the receiver for use in sampling the touch inputs.
10. The touch device of claim 9, wherein the sampling frequency generation circuit comprises:
at least first and second voltage controllable oscillators configured to generate the first sampling frequencies, respectively; and
a clock switch, coupled between the receiver and each of the first and second voltage controllable oscillators, configured to control, in response to a control signal received from the MCU, which of the first and second sampling frequencies are provided to the receiver for use in sampling the touch inputs.
11. The touch device of claim 9, wherein the microcontroller is further configured to detect noise that interferes with the first sampling frequency, to cause the receiver to continue to sample the touch inputs from the touch panel using only the second sampling frequency while changing the first sampling frequency to a first candidate sampling frequency that is not interfered with by the detected noise, and to cause the touch receiver to sample the touch inputs from the touch panel in the first and second successive time frames using the first candidate and second sampling frequencies, respectively.
12. The touch device of claim 11, wherein to change the first sampling frequency to the first candidate sampling frequency the MCU is configured to iteratively adjust the first sampling frequency by a predetermined amount to an adjusted frequency, and to determine at each iteration if noise interferes with the adjusted frequency.
13. The touch device of claim 11, wherein the MCU is configured to, after a period of time, change the first candidate frequency back to the first frequency, and cause the receiver to sample the touch inputs from the touch panel in the first and second successive time frames using the first and second sampling frequencies, respectively.
14. The touch device of claim 11, wherein the MCU is configured to detect noise that interferes with the second sampling frequency, to cause the receiver to continue to sample touch inputs from the touch panel using only the first candidate sampling frequency while changing the second sampling frequency to a second candidate sampling frequency that is not interfered with by the detected noise, and to cause the receiver to sample touch inputs from the touch panel in the first and successive time frames using the first candidate and second candidate sampling frequencies, respectively.
15. The touch device of claim 10, wherein the sampling frequency generation circuit comprises:
at least a third voltage controllable oscillator, configured to generate a third sampling frequency, wherein the clock switch is coupled between the receiver and each of the first, second, and third voltage controllable oscillators.