Apparatus, method and computer program product providing a transport format that is compatible with another transport format that uses spreading codes

• US 20070201408A1
• Filed: 02/08/2007
• Published: 08/30/2007
• Est. Priority Date: 02/08/2006
• Status: Abandoned Application

• Current Assignee: Nokia Corporation
• Original Assignee: Nokia Corporation
• Inventors: Pajukoski, Kari, Tiirola, Esa
• Application Number:
  US11/703,986
• Publication Number:
  US 20070201408A1
• Time in Patent Office: Days
• US Class Current: 370/335
• CPC Class Codes: H04B 1/69 Spread spectrum techniques
• CPC Class Codes: H04B 1/707 using direct sequence modulation
• CPC Class Codes: H04J 13/00 Code division multiplex systems for frequency hopping H04B1/713
• CPC Class Codes: H04J 13/0048 Walsh

Abstract

Either a first transport format or a second transport format is selected to transmit information corresponding to an input symbol sequence. The transport formats fit information into a timeslot having a predetermined duration. Based upon the selected transport format, either the information is created from the input symbol sequence using the first transport format or is created from the input symbol sequence using the second transport format. Creating the information for transmission using the first transport format applies a spreading code to the input symbol sequence. The information for transmission is transmitted in a selected timeslot having the predetermined duration. Creating and transmitting the information using the first transport format causes the transmitted information to occupy a first frequency band. Creating and transmitting the information using the second transport format causes the transmitted information to occupy a second frequency band that partially overlaps the first frequency band.

Claims

1. A method comprising:

selecting either a first transport format or a second transport format to transmit information corresponding to an input symbol sequence, each of the transport formats fitting information for transmission into a timeslot having a predetermined duration; and

based upon the selected transport format, either creating the information for transmission from the input symbol sequence using the first transport format or creating the information for transmission from the input symbol sequence using the second transport format, wherein creating the information for transmission using the first transport format comprises applying at least one spreading code to the input symbol sequence; and

transmitting the information for transmission in a selected timeslot having the predetermined duration, wherein creating and transmitting the information using the first transport format causes the transmitted information to occupy a first frequency band, and wherein creating and transmitting the information using the second transport format causes the transmitted information to occupy a second frequency band that at least partially overlaps the first frequency band.

2. The method of claim 1, wherein the method is performed by a first apparatus and wherein creating the information for transmission using the second transport format is performed so that the transmitted information is orthogonal to second information transmitted by another apparatus performing the method to transmit the second information using the second transport format.

3. The method of claim 2, wherein orthogonality is created at least by using different spreading codes having spreading factors for each of the first and other apparatus, the spreading codes applied during creating the information for transmission from the input symbol sequence using the second transport format.

4. The method of claim 3, wherein the spreading codes comprise one of constant amplitude zero autocorrelation codes or Walsh-Hadamard codes.

5. The method of claim 2, wherein orthogonality is created at least by using different phase vectors for each of the first and other apparatus, the phase vectors applied during creating the information for transmission from the input symbol sequence using the second transport format.

6. The method of claim 1, wherein each transport format has the duration of ⅔

millisecond, includes 2560 chips used to store information, and is transmitted using a chip rate of 3.84 million chips per second.

7. The method of claim 1, wherein the second transport format comprises a plurality of data blocks having cyclic prefixes, and wherein creating the information for transmission from the input symbol sequence using the second transport format further comprises:

spreading a plurality of symbols in the symbol sequence using a user-specific spreading code having a spreading factor;

mapping the spread symbols into a number of mapped symbols, each mapped symbol comprising a portion of one of the plurality of spread symbols;

adding a cyclic prefix to each of the mapped symbols to create data blocks; and

adding a pilot data block, comprising a pilot symbol and a cyclic prefix, to the data blocks to create the information for transmission.

8. The method of claim 7, wherein the number of mapped symbols is less than or equal to the spreading factor.

9. The method of claim 1, wherein the second transport format comprises a plurality of data blocks having cyclic prefixes, and wherein creating the information for transmission from the input symbol sequence using the second transport format further comprises:

compressing a plurality of symbols in the symbol sequence into a symbol repetition block;

repeating the symbol repetition block a first predetermined number of times to create repeated blocks;

adding a cyclic prefix to the repeated blocks to create a data block;

performing compressing, repeating, and adding a second predetermined number of times in order to create a predetermined number of data blocks;

adding a pilot data block, comprising a pilot symbol and a cyclic prefix, to the data blocks; and

using a phase vector, modulating the data blocks and the pilot data block to create the information for transmission.

10. The method of claim 1, wherein selecting further comprises selecting the first transport format in response to a data rate being within a first data rate range and selecting the second transport format in response to the data rate being within a second data rate range.

11. The method of claim 1, wherein selecting further comprises selecting the first transport format in response to a scheduled transmission of physical layer control signaling and selecting the second transport format in response to a scheduled transmission of data.

12. An apparatus comprising:

a controller configured to select either a first transport format or a second transport format to transmit information corresponding to an input symbol sequence, each of the transport formats fitting information for transmission into a timeslot having a predetermined duration; and

at least one transmitter configured, responsive to the controller and based upon the selected transport format, either to create the information for transmission from the input symbol sequence using the first transport format or to create the information for transmission from the input symbol sequence using the second transport format, wherein the at least one transmitter is configured, when creating the information for transmission using the first transport format, to apply at least one spreading code to the input symbol sequence, the at least one transmitter configured to transmit the information for transmission in a selected timeslot having the predetermined duration, wherein creation and transmission of the information using the first transport format causes the transmitted information to occupy a first frequency band, and wherein creation and transmission of the information using the second transport format causes the transmitted information to occupy a second frequency band that at least partially overlaps the first frequency band.

13. The apparatus of claim 12, wherein the controller and at least one transmitter are formed at least in part on at least one integrated circuit.

14. The apparatus of claim 12, wherein the at least one data processor is further configured to create the information using the second transport format so that the transmitted information is orthogonal to information transmitted by other apparatus using the second transport format.

15. The apparatus of claim 12, wherein each transport format has the duration of ⅔

millisecond, includes 2560 chips used to store information, and is transmitted using a chip rate of 3.84 million chips per second.

16. The apparatus of claim 12, wherein the second transport format comprises a plurality of data blocks having cyclic prefixes, and wherein the at least one transmitter comprises:

a plurality of multipliers configured to multiply a plurality of symbols in the symbol sequence by a user-specific code having a spreading factor, the plurality of multipliers creating a plurality of spread symbols;

a mapping module configured to map the spread symbols into a number of mapped symbols, each mapped symbol comprising a portion of one of the plurality of spread symbols;

a cyclic prefix addition module configured to add a cyclic prefix to each of the mapped symbols to create data blocks; and

a pilot addition module configured to add a pilot data block, comprising a pilot symbol and a cyclic prefix, to the data blocks to create the information for transmission.

17. The apparatus of claim 12, wherein the second transport format comprises a plurality of data blocks having cyclic prefixes, and wherein the at least one transmitter comprises:

a compression module configured to compress a plurality of symbols in the symbol sequence into a symbol repetition block;

a repetition module configured to repeat the symbol repetition block a first predetermined number of times to create repeated blocks;

a cyclic prefix addition module configured to add a cyclic prefix to the repeated blocks to create a data block, wherein the compression module, repetition module, and cyclic prefix addition module operate in order to create a predetermined number of data blocks;

a pilot addition module configured to add a pilot data block, comprising a pilot symbol and a cyclic prefix, to the data blocks; and

a modulation module configured to use a phase vector to modulate the data blocks and the pilot data block to create the information for transmission.

18. The apparatus of claim 12, wherein the controller is configured to select the first transport format in response to a data rate being within a first data rate range and to select the second transport format in response to the data rate being within a second data rate range.

19. The apparatus of claim 12, wherein the controller is configured to select the first transport format in response to a scheduled transmission of physical layer control signaling and to select the second transport format in response to a scheduled transmission of data.

20. A computer program product tangibly embodying a program of machine-readable instructions executable by at least one data processor to perform operations comprising:

selecting either a first transport format or a second transport format to transmit information corresponding to an input symbol sequence, each of the transport formats fitting information for transmission into a timeslot having a predetermined duration; and

based upon the selected transport format, either creating the information for transmission from the input symbol sequence using the first transport format or creating the information for transmission from the input symbol sequence using the second transport format, wherein creating the information for transmission using the first transport format comprises applying at least one spreading code to the input symbol sequence;

transmitting the information for transmission in a selected timeslot having a predetermined duration, wherein creating and transmitting the information using the first transport format causes the transmitted information to occupy a first frequency band, and wherein creating and transmitting the information using the second transport format causes the transmitted information to occupy a second frequency band that at least partially overlaps the first frequency band.

21. The computer program product of claim 20, wherein the operations are performed by a first apparatus and wherein the operation of creating the information for transmission using the second transport format is performed so that the transmitted information is orthogonal to second information transmitted by another apparatus performing the operations to transmit the second information using the second transport format.

22. The computer program product of claim 20, wherein each transport format has the duration of ⅔

millisecond, includes 2560 chips used to store information, and is transmitted using a chip rate of 3.84 million chips per second.

23. A method comprising:

receiving first information using a first transport format, the first information received in a timeslot having a predetermined duration, wherein the first information occupies a first frequency band;

converting, at least by applying at least one spreading code to the received first information, the received first information to first output data;

receiving second information using a second transport format, the second information received in a timeslot having the predetermined duration, wherein the second information occupies a second frequency band that at least partially overlaps the first frequency band, and wherein the first and second information are received at the same time in a selected timeslot; and

converting the received second information to second output data.

24. The method of claim 23, wherein the second transport format comprises a plurality of data blocks having cyclic prefixes, wherein receiving second information comprises receiving at least one time-domain signal using at least one antenna, and wherein converting the received second information to second output data comprises:

transforming each of the at least one time-domain signals to a corresponding frequency-domain signal;

for each of the frequency-domain signals, applying channel estimates to a corresponding one of the frequency-domain signals to create a corresponding channel corrected signal;

applying equalization weights to all of the channel corrected signals to create an equalized signal;

transforming the equalized signal to a second time-domain signal; and

despreading the second time-domain signal to create the second output data.

25. The method of claim 24, wherein despreading further comprises demapping symbols in the second time domain signal to create demapped symbols and, using at least one orthogonal spreading code, despreading the demapped signals to create the second output data.

26. The method of claim 24, wherein despreading further comprises determining a single symbol repetition block from a plurality of symbol repetition blocks in the second time-domain signal and decompressing the single symbol repetition block to create the second output data.

27. An apparatus comprising:

a first receiver configured to receive first information using a first transport format and to convert, at least by application of at least one spreading code to the received first information, the received first information to first output data, the first information received in a timeslot having a predetermined duration, wherein the first information occupies a first frequency band;

a second receiver configured to receive second information using a second transport format and to convert the received second information to second output data, the second information received in a timeslot having the predetermined duration, wherein the second information occupies a second frequency band that at least partially overlaps the first frequency band, and wherein the first and second information are received at the same time in a selected timeslot.

28. The apparatus of claim 27, wherein the first and second receivers are formed at least in part on at least one integrated circuit.

29. The apparatus of claim 27, wherein the second transport format comprises a plurality of data blocks having cyclic prefixes, the apparatus comprises at least one antenna receiving at least one time-domain signal, and wherein the second receiver comprises:

a first transform device for each of the at least one antennas, each first transform device configured to transform a corresponding one of the at least one time-domain signals to a corresponding frequency-domain signal;

a channel correction device for each of the first transform devices, each channel correction device configured to apply channel estimates to a corresponding one of the frequency-domain signals to create a corresponding channel corrected signal;

a frequency equalization device configured to apply equalization weights to all of the channel corrected signals to create an equalized signal;

a second transform device configured to transform the equalized signal to a second time-domain signal; and

a despreader module configured to despread the time-domain signal.

30. The apparatus of claim 29, wherein the despreader module is configured to demap symbols in the second time domain signal to create demapped symbols and is configured, using at least one orthogonal spreading code, to despread the demapped signals to create the second output data.

31. The apparatus of claim 29, wherein the despreader module is configured to determine a single symbol repetition block from a plurality of symbol repetition blocks in the second time-domain signal and to decompress the single symbol repetition block to create the second output data.

32. An apparatus comprising:

at least one transmitter configured to create information for transmission from an input symbol sequence using a first transport format, the at least one transmitter configured to transmit the information for transmission in a timeslot having a predetermined duration, wherein creation and transmission of the information using the first transport format causes the transmitted information to occupy a first frequency band that at least partially overlaps a second frequency band occupied when a second transport format is used by other apparatus to transmit information within a timeslot having the predetermined duration, wherein creation of the information uses a user-specific code that provides orthogonality of the transmitted information relative to information created and transmitted using other user-specific codes, and wherein transmissions using the second transport format multiplex users through non-orthogonal user-specific spreading codes.

33. The apparatus of claim 32, wherein the at least one transmitter is formed at least in part by at least one integrated circuit.

34. The apparatus of claim 32, wherein the user-specific code is a spreading code having a spreading factor.

35. The apparatus of claim 34, wherein the spreading code comprises one of constant amplitude zero autocorrelation codes or Walsh-Hadamard codes.

36. The apparatus of claim 32, wherein the user-specific code is a phase vector.

37. The apparatus of claim 32, wherein each transport format has the duration of ⅔

millisecond, includes 2560 chips used to store information, and is transmitted using a chip rate of 3.84 million chips per second.

38. The apparatus of claim 32, wherein the first transport format comprises a plurality of data blocks having cyclic prefixes.