Orthogonal pulse polarity modulation

• US 20050254553A1
• Filed: 05/17/2004
• Published: 11/17/2005
• Est. Priority Date: 05/17/2004
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Xu, Weiyu, Yao, Richard Yuqi, Guo, Zihua, Zhu, Wenwu
• Granted Patent: US 7,636,380 B2
• Time in Patent Office: Days
• US Class Current: 375/130
• CPC Class Codes: H04B 1/71632 Signal aspects H04B1/7172 and H04B1/7176 take precedence
• CPC Class Codes: H04B 1/71637 Receiver aspects H04B1/7183 takes precedence
• CPC Class Codes: H04B 1/7172 Pulse shape in general H04L25/03834

Abstract

Orthogonal pulse polarity modulation involves wireless communication in which the polarity of modulating pulses are set responsive to positive and negative character values of a corresponding code sequence. In a described implementation, data is converted to chip waveforms, spectrum lines are removed, and pulses are appropriately shaped. For example, a data bit stream may be converted into chip waveforms using a bit stream-to-symbol segmenter, a symbol-to-code sequence mapper, and a code sequence-to-chip waveform transformer. The polarities of respective individual chips in a given chip waveform match the signs of respective individual characters in a corresponding code sequence.

Claims

1. A device that is capable of transmitting wireless communications, the device adapted to modulate data using orthogonal code sequences to convert the data into chip waveforms having chip polarity information that encodes sign value information from the orthogonal code sequences.

2. The device as recited in claim 1, wherein the sign value information within a given code sequence is carried in a corresponding chip waveform by chip polarities of individual chips of the corresponding chip waveform.

3. The device as recited in claim 2, wherein sign value information for respective characters of the given code sequence is reflected in the corresponding chip waveform by chip polarities of respective individual chips of the corresponding chip waveform.

4. The device as recited in claim 1, wherein the device is also adapted to modulate the data by removing at least one spectrum line from a power spectrum density of a wireless signal carrying the modulated data.

5. The device as recited in claim 4, wherein the device is further adapted to remove the at least one spectrum line by balancing chip polarities of the chip waveforms.

6. The device as recited in claim 5, wherein the device is further adapted to balance chip polarities of the chip waveforms by multiplying characters of the orthogonal code sequences by pseudorandom numbers.

7. The device as recited in claim 1, wherein the device is also adapted to modulate the data using a pulse-shaping baseband waveform that is derived responsive to a power spectrum density constraint and a received power level.

8. The device as recited in claim 7, wherein the device is further adapted to modulate the data using a pulse-shaping baseband waveform that comprises a fifth-order Gaussian derivative waveform.

9. The device as recited in claim 8, wherein an impulse width parameter of the fifth-order Gaussian derivative waveform is set between 0.055 and 0.065 nanoseconds, inclusive.

10. The device as recited in claim 9, wherein the impulse width parameter of the fifth-order Gaussian derivative waveform is set to 0.0645 nanoseconds.

11. The device as recited in claim 1, wherein the device is also adapted to modulate the data using a pulse-shaping baseband waveform that comprises a root-raised-cosine waveform with a roll-off factor set between 0.2 and 0.5, inclusive.

12. A device comprising:

a transceiver that is capable of transmitting wireless communications from the device;

a processor; and

media including data signal modulation logic that is at least partially executable by the processor, the data signal modulation logic capable of removing at least one spectrum line in a power spectrum density of a data signal to be transmitted via the transceiver by balancing chip polarities in chip waveforms created for transmission of the data signal.

13. The device as recited in claim 12, wherein the data signal modulation logic is further capable of removing the at least one spectrum line in the power spectrum density of the data signal by multiplying a pseudorandom number sequence with code sequences corresponding to the chip waveforms.

14. The device as recited in claim 13, wherein pseudorandom numbers of the pseudorandom number sequence that are multiplied with the code sequences are selected from a group comprising “

+1” and

“

−

1”

.

15. The device as recited in claim 12, wherein the data signal modulation logic is also capable of modulating the data signal using a pulse-shaping baseband waveform that is derived responsive to a power spectrum density constraint and to frequency-dependent path loss.

16. The device as recited in claim 12, wherein the data signal modulation logic is also capable of modulating the data signal using chip waveforms having pulses with positive and negative polarities that are set responsive to positive and negative sign values of corresponding code sequences.

17. The device as recited in claim 12, wherein the data signal modulation logic is comprised of one or more of at least one analog component, hardware, software, or firmware.

18. One or more processor-accessible media comprising processor-executable instructions that, when executed, direct a device to perform actions comprising:

segmenting a data bit stream into multiple symbols;

mapping the segmented symbols into multiple corresponding code sequences; and

transforming the mapped code sequences into corresponding chip waveforms in which chip polarities match sign values of the corresponding code sequences.

19. The one or more processor-accessible media as recited in claim 18, wherein the chip polarities match the sign values by positive chip polarities matching positive sign values and negative chip polarities matching negative sign values.

20. The one or more processor-accessible media as recited in claim 18, wherein the chip polarities match the sign values by positive chip polarities matching negative sign values and negative chip polarities matching positive sign values.

21. The one or more processor-accessible media as recited in claim 18, wherein the corresponding code sequences are orthogonal to one another.

22. The one or more processor-accessible media as recited in claim 18, comprising the processor-executable instructions that, when executed, direct the device to perform a further action comprising:

removing at least one spectrum line from a power spectrum density by balancing the chip polarities in the chip waveforms.

23. The one or more processor-accessible media as recited in claim 22, wherein the action of removing comprises an action of:

multiplying the multiple code sequences by a pseudorandom number sequence.

24. The one or more processor-accessible media as recited in claim 18, wherein each chip of each chip waveform is realized as at least one pulse.

25. The one or more processor-accessible media as recited in claim 24, comprising the processor-executable instructions that, when executed, direct the device to perform a further action comprising:

shaping the at least one pulse of each chip using a pulse-shaping baseband waveform that comprises a fifth-order Gaussian derivative.

26. The one or more processor-accessible media as recited in claim 25, wherein the action of shaping comprises an action of:

shaping the at least one pulse of each chip using the pulse-shaping baseband waveform that comprises the fifth-order Gaussian derivative in which an impulse width parameter of the fifth-order Gaussian derivative is set between 0.055 and 0.065 nanoseconds, inclusive.

27. The one or more processor-accessible media as recited in claim 18, wherein the one or more processor-accessible media comprise at least one of (i) one or more storage media or (ii) one or more transmission media.

28. An arrangement for orthogonal pulse polarity modulation, comprising:

conversion means for converting data to code sequences;

shaping means for shaping pulses forming chips of chip waveforms used in transmission of the data as modulated; and

removal means for removing spectrum lines from a power spectrum density of the transmission of the modulated data;

wherein chip polarities within a given chip waveform vary in accordance with sign values of a corresponding code sequence.

29. The arrangement as recited in claim 28, further comprising:

transceiver means for transmitting without spectrum lines the modulated data using the shaped pulses.

30. The arrangement as recited in claim 28, wherein the conversion means comprises:

segmentation means for segmenting the data into M-bit symbols.

31. The arrangement as recited in claim 30, wherein the conversion means further comprises:

map means for mapping the M-bit symbols to corresponding code sequences of a set of 2^M code sequences.

32. The arrangement as recited in claim 28, wherein the shaping means further comprises:

transformation means for transforming the code sequences into corresponding chip waveforms.

33. The arrangement as recited in claim 28, wherein the removal means comprises:

balance means for balancing chip polarities of each chip waveform.

34. The arrangement as recited in claim 28, wherein the arrangement comprises at least one of (i) one or more processor-accessible media or (ii) at least one device.