Frequency offset differential pulse position modulation
View Patent ↗The present invention provides such a need by utilizing a frequency offset differential pulse position modulation scheme to transmit data between computing devices within a wireless network system. The differential pulse position modulation component of the scheme enables the present invention to provide relative immunity to interference for the system. In particular, such immunity from interference is achieved by utilizing a blanking time between pulse positions, which is large enough to allow the interference between frequency offset-differential pulse position modulation pulses to subside. The frequency offset component of the scheme enables the system to utilize multiple frequency channels to enable the system to achieve higher data rates. In particular, by utilizing a time offset between the frequency channels, the blanking time can be reduced, thereby increasing the amount of data that can be transmitted with a set period of time.
1. A method of transmitting data in a bit stream, the method comprising:
identifying a first pulse transmission time in a first time window for a first bit sequence of a bit stream based on a first value of the first bit sequence;
transmitting a first pulse at the identified first pulse transmission time using a first frequency;
identifying a second pulse transmission time in a second time window for a second bit sequence of the bit stream based on a second value of the second bit sequence; and
transmitting a second pulse at the identified second pulse transmission time using a second frequency, wherein the first frequency is different than the second frequency, and further wherein the first time window and the second time window overlap at least partially in time.
2. The method of claim 1 , further comprising selecting an antenna of a plurality of antennas to transmit the first pulse.
3. The method of claim 2 , wherein the antenna is selected based on a signal strength of the first pulse.
4. The method of claim 1 , wherein the first bit sequence comprises a plurality of bits.
5. The method of claim 1 , wherein the second time window is offset from the first time window by a fixed amount of time.
6. The method of claim 1 , wherein a length in time of the first time window is based on a number of bits in the first bit sequence.
7. The method of claim 1 , wherein the first pulse transmission time is identified by selecting a counter value based on the first value of the first bit sequence.
8. The method of claim 7 , wherein the first pulse is transmitted when the counter value is zero.
9. The method of claim 1 , further comprising identifying a third pulse transmission time in a third time window for a third bit sequence of the bit stream based on a third value of the third bit sequence; and
transmitting a third pulse at the identified third pulse transmission time using a third frequency, wherein the third frequency is different than the first frequency and the second frequency, and further wherein the first time window, the second time window, and the third time window overlap at least partially in time.
10. An encoder comprising:
a transmit physical layer module configured to identify a first pulse transmission time in a first time window for a first bit sequence of a bit stream based on a first value of the first bit sequence;
to trigger transmission of a first pulse at the identified first pulse transmission time using a first frequency;
to identify a second pulse transmission time in a second time window for a second bit sequence of the bit stream based on a second value of the second bit sequence; and
to trigger transmission of a second pulse at the identified second pulse transmission time using a second frequency, wherein the first frequency is different than the second frequency, and further wherein the first time window and the second time window overlap at least partially in time.
11. The encoder of claim 10 , further comprising a transmit media access control layer module configured to select an antenna of a plurality of antennas to transmit the first pulse.
12. The encoder of claim 11 , wherein the antenna is selected based on a signal strength of the first pulse.
13. The encoder of claim 10 , wherein the first bit sequence comprises a plurality of bits.
14. The encoder of claim 10 , wherein the second time window is offset from the first time window by a fixed amount of time.
15. The encoder of claim 10 , wherein a length in time of the first time window is based on a number of bits in the first bit sequence.
16. The encoder of claim 10 , wherein the first pulse transmission time is identified by selecting a counter value based on the first value of the first bit sequence.
17. The encoder of claim 16 , wherein the first pulse is transmitted when the counter value is zero.
18. A device comprising:
an encoder comprising a transmit physical layer module configured to identify a first pulse transmission time in a first time window for a first bit sequence of a bit stream based on a first value of the first bit sequence;
to trigger transmission of a first pulse at the identified first pulse transmission time using a first frequency;
to identify a second pulse transmission time in a second time window for a second bit sequence of the bit stream based on a second value of the second bit sequence; and
to trigger transmission of a second pulse at the identified second pulse transmission time using a second frequency, wherein the first frequency is different than the second frequency, and further wherein the first time window and the second time window overlap at least partially in time; and
a transmitter operably coupled to the encoder and to a plurality of antennas and configured to transmit the first pulse and the second pulse using an antenna of the plurality of antennas.
19. The device of claim 18 , further comprising the plurality of antennas.
20. The device of claim 18 , wherein the encoder further comprises a transmit media access control layer module configured to select the antenna to transmit the first pulse.
21. The device of claim 20 , wherein the antenna is selected based on a signal strength of the first pulse.
22. The device of claim 18 , wherein the first pulse and the second pulse are transmitted with different antennas of the plurality of antennas.
23. The device of claim 18 , wherein the second time window is offset from the first time window by a fixed amount of time.
24. The device of claim 18 , wherein a length in time of the first time window is based on a number of bits in the first bit sequence.
25. The device of claim 18 , wherein the first pulse transmission time is identified by selecting a counter value based on the first value of the first bit sequence.
26. The device of claim 25 , wherein the first pulse is transmitted when the counter value is zero.