Sounding reference signal arrangement

• US 20090181687A1
• Filed: 01/08/2009
• Published: 07/16/2009
• Est. Priority Date: 01/08/2008
• Status: Active Grant

• Current Assignee: HMD Global Oy
• Original Assignee: Nokia Solutions and Networks US LLC (Nokia Corporation)
• Inventors: Pajukoski, Kari, Tiirola, Esa, Hooli, Kari
• Granted Patent: US 8,761,195 B2
• Time in Patent Office: Days
• US Class Current: 455/450
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 5/0016 Time-frequency-code
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals

Abstract

A method, apparatus, and computer program embodied on a computer-readable medium to create an uplink message to be transmitted to a base station, the created uplink message comprises a sounding reference signal based on accessed data. An uplink scheduling grant signal is received via downlink, from the base station, in response to the transmission of the uplink message. An uplink data transmission is transmitted to the base station responsive to the received uplink scheduling grant signal.

Claims

1. A method, comprising:

creating an uplink message to be transmitted to a base station, the created uplink message comprises a sounding reference signal based on accessed data;

receiving uplink scheduling grant signal via downlink from the base station in response to the transmission of the uplink message; and

transmitting to the base station uplink data transmission responsive to the received uplink scheduling grant signal.

2. The method according to claim 1, further comprising:

storing the data related to reference signal sequences, to form a desired cyclic shift separation between the reference signal sequences, and to support a tree-based bandwidth assignment, the data being received from a user interface or from the base station.

3. The method according to claim 1, further comprising:

forming the sounding reference signal based on existing demodulation reference signals;

selecting the sounding reference signal to support a tree-based bandwidth assignment; and

adapting the sounding reference signal to provide maximum cyclic shift separation.

4. The method according to claim 3, further comprising:

reserving sufficient bandwidth at least for physical uplink control channel when forming the sounding reference signal based on existing demodulation reference signal signals;

selecting a bandwidth allocation based on a discrete Fourier transforms and repetition factor sizes when forming the sounding reference signal based on existing demodulation reference signal signals; and

configuring the maximum cyclic shift separation between eight cyclic shifts to result in a sounding reference signal sequence length divisible by eight when a bandwidth of the sounding reference signal is a multiple of four resource blocks.

5. The method according to claim 4, further comprising:

determining sufficient bandwidth to reserve for the physical uplink control channel.

6. The method according to claim 5, further comprising:

configuring at least two resource blocks to be reserved for the physical uplink control channel.

7. The method according to claim 4, wherein the demodulation reference signal signals comprises desired discrete Fourier transforms and repetition factor sizes, and

wherein the discrete Fourier transforms sizes are two, three, or five.

8. The method according to claim 3, further comprising:

supporting the tree-based bandwidth assignment based on a selection of sounding reference signal bandwidths in which a larger bandwidth is evenly divisible by a smaller bandwidth.

9. The method according to claim 3, wherein the cyclic shift separation between possible cyclic shifts is maximized, and

wherein the cyclic shift is based on a sequence length and on a number of the possible cyclic shifts.

10. The method according to claim 9, wherein the cyclic shift is a cyclic shift indicator received from base station multiplied with a sequence length and divided with the number of possible cyclic shifts, and

wherein the number of possible cyclic shifts is eight.

11. The method according to claim 1, wherein a bandwidth of the sounding reference signal comprises a minimum of four resource blocks.

12. The method according to claim 1, further comprising:

calculating an actual amount of cyclic shift in symbols using equation 1, which relates to a time domain generation of the cyclic shifts,

$\mathrm{Cyclic\_shift}<br><br>\mathrm{\_symbols}<br><br>\mathrm{\_SRS}=\frac{\mathrm{cyclic\_shift}<br><br>\mathrm{\_value}<br><br>\mathrm{\_SRS}\times <br><br>\mathrm{SRS\_length}}{8}$

wherein possible cyclic shift values (cyclic_shift_value_SRS) are, 0, 1, . . . , and 7.

13. The method according to claim 12, further comprising:

generating corresponding cyclic shifts by utilizing basic properties of discrete Fourier transformation;

generating a cyclic shift of l by multiplying the nth element of the sequence discrete Fourier transformation with exp(j2π

ln/N), where j=sqrt(−

1) and N is the length of sequence; and

realizing the cyclic shift of the equation 1 in frequency domain by multiplying the nth element of the SRS sequence discrete Fourier transformation with exp(j2π

n×

Cyclic_shift_symbols_SRS/SRS_length)=exp(j2π

n×

cyclic_shift_value_SRS/8).

14. A method, comprising:

receiving, from a mobile station, an uplink message comprising a sounding resource signal allocation bandwidth;

transmitting uplink scheduling grant signal via downlink to the mobile station; and

receiving, from the mobile station, uplink data transmission responsive to the transmitted uplink scheduling grant signal.

15. The method according to claim 14, further comprising:

forming the sounding reference signal based on existing demodulation reference signals;

selecting the sounding reference signal to support a tree-based bandwidth assignment; and

adapting the sounding reference signal to provide maximum cyclic shift separation.

16. The method according to claim 14, further comprising:

configuring the uplink message to include bandwidth reserved for physical uplink control channel.

17. The method according to claim 16, further comprising:

configuring two resource blocks to be reserved for the physical uplink control channel.

18. The method according to claim 14, wherein the demodulation reference signal signals include desired discrete Fourier transforms and repetition factor sizes of two, three, or five.

19. The method according to claim 14, further comprising:

supporting the tree-based bandwidth assignment based on a selection of sounding reference signal bandwidths in which a larger bandwidth is evenly divisible by a smaller bandwidth

20. The method according to claim 14, wherein the cyclic shift separation between possible cyclic shifts is maximized, and

wherein the cyclic shift is based on a sequence length and on a number of the possible cyclic shifts.

21. The method according to claim 14, further comprising:

providing a minimum sounding reference signal bandwidth with four resource blocks.

22. An apparatus, comprising:

a transmitter configured to transmit to a base station a created uplink message comprising a sounding reference signal; and

a receiver configured to receive uplink scheduling grant signal via downlink from the base station,

wherein the transmitter is further configured to transmit to the base station uplink data transmission responsive to the received uplink scheduling grant signal.

23. The apparatus according to claim 22, further comprising:

a storage configured to store the data related to reference signal sequences, to form a desired cyclic shift separation between reference signal sequences, and to support a tree-based bandwidth assignment, the data being received from a user interface or from the base station.

24. The apparatus according to claim 22, wherein the processor is further configured to

form the sounding reference signal based on existing demodulation reference signal,

select the sounding reference signal to support a tree-based bandwidth assignment, and

adapt the sounding reference signal to provide maximum cyclic shift separation.

25. The apparatus according to claim 24, wherein the processor if further configured to

reserve sufficient bandwidth for physical uplink control channel when the sounding reference signal is formed based on existing demodulation reference signal signals;

select bandwidth allocation based on a discrete Fourier transforms and repetition factor sizes when the sounding reference signal is formed based on existing demodulation reference signal signals; and

maximize cyclic shift separation between eight cyclic shifts to result in a sounding reference signal sequence length divisible by eight when a bandwidth of the sounding reference signal is a multiple of four resource blocks.

26. The apparatus according to claim 25, wherein the processor is further configured to determine sufficient bandwidth to reserve for the physical uplink control channel.

27. The apparatus according to claim 26, wherein two resource blocks are reserved for the protocol uplink control channel.

28. The apparatus according to claim 25, wherein the demodulation reference signal signals comprises desired discrete Fourier transforms and repetition factor sizes, and wherein the discrete Fourier transforms sizes are two, three, or five.

29. The apparatus according to claim 24, wherein the processor is further configured to support the tree-based bandwidth assignment based on a selection of sounding reference signal bandwidths in which a larger bandwidth is evenly divisible by any smaller bandwidth.

30. The apparatus according to claim 24, wherein the cyclic shift separation between possible cyclic shifts is maximized, and

wherein the cyclic shift is based on a sequence length and on a number of the possible cyclic shifts.

31. The apparatus according to claim 30, wherein the cyclic shift is a cyclic shift indicator received from a base station multiplied with a sequence length and divided with the number of the possible cyclic shifts, and

wherein the number of the possible cyclic shifts is eight.

32. The apparatus according to claim 22, wherein a bandwidth of the sounding resource signal comprises a minimum of four resource blocks.

33. The apparatus according to claim 22, further comprising:

a calculator configured to calculate an actual amount of cyclic shift in symbols using equation 1, which relates to a time domain generation of the cyclic shifts,

$\mathrm{Cyclic\_shift}<br><br>\mathrm{\_symbols}<br><br>\mathrm{\_SRS}=\frac{\mathrm{cyclic\_shift}<br><br>\mathrm{\_value}<br><br>\mathrm{\_SRS}\times <br><br>\mathrm{SRS\_length}}{8}$

wherein possible cyclic shift values (cyclic_shift_value_SRS) are, 0, 1, . . . , and 7.

34. The apparatus according to claim 22, further comprising:

a generator configured to generate corresponding cyclic shifts by utilizing basic properties of discrete Fourier transformation;

another generator configured to generate a cyclic shift of 1 by multiplying the nth element of the sequence discrete Fourier transformation with exp(j2π

ln/N), where j=sqrt(−

1) and N is the length of sequence; and

a realizing unit configured to realize the cyclic shift of the equation 1 in frequency domain by multiplying the nth element of the SRS sequence discrete Fourier transformation with exp(2π

n×

Cyclic_shift_symbols_SRS/SRS_length)=exp(2π

n×

cyclic_shift_value_SRS/8).

35. An apparatus, comprising:

a receiver configured to receiver an uplink message comprising a sounding resource signal allocation bandwidth; and

a transmitter configured to transmit uplink scheduling grant signal via downlink to a mobile station, wherein

the receiver is further configured to receive, from the mobile station, uplink data transmission responsive to the transmitted uplink scheduling grant signal.

36. The apparatus according to claim 35, wherein the sounding reference signal is configured to be formed based on existing demodulation reference signal signals, selected to support a tree-based bandwidth assignment, and adapted to provide maximum cyclic shift separation.

37. The apparatus according to claim 35, wherein the uplink message is configured to include bandwidth reserved for physical uplink control channel.

38. The apparatus according to claim 37, wherein two resource blocks are reserved for the protocol uplink control channel.

39. The apparatus according to claim 35, wherein the demodulation reference signal signals is configured to include desired discrete Fourier transforms and repetition factor sizes of two, three, or five.

40. The apparatus according to claim 35, wherein the tree-based bandwidth assignment is configured to be supported based on a selection of sounding reference signal bandwidths in which a larger bandwidth is evenly divisible by a smaller bandwidth

41. The apparatus according to claim 35, wherein the cyclic shift separation between possible cyclic shifts is maximized, and

wherein the cyclic shift is based on a sequence length and a number of the possible cyclic shifts.

42. The apparatus according to claim 35, wherein the providing a minimum sounding reference signal bandwidth is configured to be provided with a minimum of four resource blocks.

43. An apparatus, comprising:

transmitting means for transmitting to a base station a created uplink message comprising a sounding reference signal; and

receiving means for receiving uplink scheduling grant signal via downlink from the base station,

wherein the transmitting means for transmitting transmits to the base station uplink data transmission responsive to the received uplink scheduling grant signal.

44. An apparatus, comprising:

receiving means for receiving an uplink message comprising a sounding resource signal allocation bandwidth; and

transmitting means for transmitting uplink scheduling grant signal via downlink to a mobile station, wherein

receiving means for receiving, from the mobile station, uplink data transmission responsive to the transmitted uplink scheduling grant signal.

45. A computer program embodied on a computer-readable medium, the computer program being configured to control a process to perform a method, the method comprising:

creating an uplink message to be transmitted to a base station comprising a sounding reference signal based on accessed data;

receiving uplink scheduling grant signal via downlink from the base station in response to the transmission of the uplink message; and

transmitting to the base station uplink data transmission responsive to the received uplink scheduling grant signal.

46. A computer program embodied on a computer-readable medium, the computer program being configured to control a process to perform a method, the method comprising:

receiving an uplink message comprising a sounding resource signal allocation bandwidth;

transmitting uplink scheduling grant signal via downlink to a mobile station; and

receiving, from the mobile station, uplink data transmission responsive to the transmitted uplink scheduling grant signal.