Method of operating a communication device and a system, a communication device and a system including the communication device

Abstract

A communication system, such as UMTS, comprises a scheduler ( 12 ) in a first station (PS) which is able to control a user equipment (UE 1, UE 2 ). The scheduler when operating in a data transmission mode, such as HSUPA (High-Speed Uplink Packet Access) controls the user equipment with combinations of absolute grants (AG) and relative grants (RG). The relative grants serve to adapt a transmission parameter relative to a reference value. The reference value for the relative grant is selected dependent on a property of one or more of the grants. Such a property may comprise the absolute grant being an all process grant or a single process grant.

The invention claimed is: 
     
       1. A method of operating a communication device, comprising
 transmitting a first signal with a transmission parameter selected from a group consisting of: a power and a rate, 
 adapting, in response to receiving a second signal, the transmission parameter of the first signal in accordance with a value indicated by the second signal, and 
 adapting, in response to receiving a third signal, the transmission parameter of the first signal relative to a reference value, the method further comprising 
 selecting the reference value from a value of a first transmission parameter at a first preceding time instant and a value of a second transmission parameter at a second preceding time instant, the selection being dependent on a property of at least one of the second and third signals. 
 
     
     
       2. The method as claimed in  claim 1 , in which the first signal comprises data transmitted in groups of transmission time intervals (TTI), wherein the first preceding time instant is a first preceding TTI and the second preceding time instant is a second preceding TTI. 
     
     
       3. The method as claimed in  claim 2 , wherein the first preceding TTI is the a correspondingly numbered TTI in a preceding group of TTIs. 
     
     
       4. The method as claimed in  claim 2 , wherein the second TTI is one of: an immediately preceding TTI, a most recent preceding TTI in which a second signal was applied, an earliest TTI in which a second signal was applied after the first preceding TTI, a most recent preceding TTI in which a third signal was applied, an earliest TTI in which a third signal was applied after the first preceding TTI, a TTI in which the a lowest-valued one of the second and third signals was applied after the first preceding TTI, and a TTI in which a highest-valued one of the second and third signals was applied after the first preceding TTI. 
     
     
       5. The method as claimed in  claim 2 , wherein the first and second preceding TTIs are the same. 
     
     
       6. The method as claimed in  claim 1 , wherein the reference value is selected to he be one of: the value of the second transmission parameter in the second preceding TTI if the communication device receives a second signal applicable to a TTI later than the first preceding TTI, and the value of the first transmission parameter in the first preceding TTI. 
     
     
       7. The method as claimed in  claim 1 , wherein the data is transmitted in a plurality of processes, and wherein the reference value is selected depending on whether a preceding second signal applicable to a TTI later than the first preceding TTI has the property of being an all process second signal or a single process second signal. 
     
     
       8. A The method as claimed in  claim 7 , wherein in the a case of an all process second signal the reference value is selected to be the value of the second transmission parameter in the second preceding TTI and in the case of a single process second signal the reference value is selected to be the value of the first transmission parameter in the first preceding TTI. 
     
     
       9. The method as claimed in  claim 1 , wherein at least one of the first and second transmission parameters is a power available to transmit data. 
     
     
       10. The method as claimed in  claim 1 , wherein at least one of the first and second transmission parameters is a rate available for data transmission. 
     
     
       11. The method as claimed in  claim 1 , wherein at least one of the first and second transmission parameters is a ratio between the power available for data transmission and the power used for transmission of a control signal. 
     
     
       12. The method as claimed in  claim 1 , wherein at least one of the first and second transmission parameters is a power used for data transmission. 
     
     
       13. The method as claimed in  claim 1 , wherein at least one of the first and second transmission parameters is a rate used for data transmission. 
     
     
       14. The method as claimed in  claim 1 , wherein at least one of the first and second transmission parameters is a ratio between the power used for data transmission and the power used for transmission of a control signal. 
     
     
       15. The method as claimed in  claim 1 , wherein the first transmission parameter is a ratio between the power used for data transmission and a power used for transmission of a control signal, and the second transmission parameter is a ratio between the power available for data transmission and a power used for transmission of a control signal. 
     
     
       16. The method as claimed in  claim 1 , wherein the a relevant property of the second signal is its value compared to the value of the first transmission parameter in the first preceding TTI. 
     
     
       17. The method as claimed in  claim 16 , wherein the reference value is selected to be the value of the second transmission parameter in the second preceding TTI in response to the second signal having a value below the value of the first transmission parameter in the first preceding TTI, and wherein the reference value is selected to be the value of the first transmission parameter in the first preceding TTI in response to the second signal having a value above the value of the first transmission parameter in the first preceding TTI. 
     
     
       18. The method as claimed in  claim 1 , wherein the property is related to the third signal, wherein in response to the third signal being a decrement, the reference value is selected to be a first value, and in response to the third signal being an increment the reference value is selected to be a second value. 
     
     
       19. The method as claimed in  claim 18 , wherein the first value is the lower of the value of the first transmission parameter in the first preceding TTI and the value of the second transmission parameter in the second preceding TTI, and wherein the second value is one of the value of the first transmission parameter in the first preceding TTI, the value of the second transmission parameter in the second preceding TTI, and the higher of the value of the first transmission parameter in the first preceding TTI and the value of the second transmission parameter in the second preceding TTI. 
     
     
       20. The method as claimed in  claim 1 , wherein the second signal comprises an absolute grant (AG) and the third signal comprises a relative grant (RG), wherein the reference value is selected to be a first value if a single-process absolute grant received in a predetermined time window is identified with a same HARM HARQ (Hybrid Automatic Repeat Requests) process as the relative grant in question, and wherein the reference value is selected to be a second value if a single-process absolute grant received in the predetermined time window is identified with a different HARQ (Hybrid Automatic Repeat Request) process from that of the relative grant in question. 
     
     
       21. Software A non-transitory computer-readable medium comprising instructions executable by a processor for controlling the operation of a communication device in accordance with the method as claimed in  claim 1 , the instructions when executed;
 transmitting a first signal with a transmission parameter selected from a group consisting of: a power and a rate, 
 adapting, in response to receiving a second signal, the transmission parameter of the first signal in accordance with a value indicated by the second signal, and 
 adapting, in response to receiving a third signal, the transmission parameter of the first signal relative to a reference value, the method further comprising 
 selecting the reference value from a value of a first transmission parameter at a first preceding time instant and a value of a second transmission parameter at a second preceding time instant, the selection being dependent on a property of at least one of the second and third signals. 
 
     
     
       22. A communication device comprising
 a transmitter for transmitting a first signal with a transmission parameter selected from a group consisting of: a power and a rate, 
 a control means for adapting, in response to receiving a second signal, the transmission parameter of the first signal in accordance with a value indicated by the second signal and for adapting, in response to a third signal, the transmission parameter of the first signal relative to a reference value, the communication device further comprising 
 selection means for selecting, dependent on a property of at least one of the second and third signals, the reference value from one of: a value of a first transmission parameter at a first preceding time instant and a value of a second transmission parameter at a second preceding time instant. 
 
     
     
       23. The device as claimed in  claim 22 , in which the first signal comprises data transmitted in groups of transmission time intervals (TTI), wherein the first preceding time instant is a first preceding TTI and the second preceding time instant is a second preceding TTI. 
     
     
       24. The device as claimed in  claim 23 , wherein the first preceding TTI is a correspondingly numbered TTI in the preceding group of TTIs. 
     
     
       25. The device as claimed in  claim 22 , wherein at least one of the first and second transmission parameters is a power available to transmit data. 
     
     
       26. The device as claimed in  claim 22 , wherein at least one of the first and second transmission parameters is a rate available for data transmission. 
     
     
       27. The device as claimed in  claim 22 , wherein at least one of the first and second transmission parameters is a ratio between a power available for data transmission and a power used for transmission of a control signal. 
     
     
       28. The device as claimed in  claim 22 , wherein at least one of he the first and second transmission parameters is a power used for data transmission. 
     
     
       29. The device as claimed in  claim 22 , wherein at least one of the first and second transmission parameters is a rate used for data transmission. 
     
     
       30. The device as claimed in  claim 22 , wherein at least one of the first and second transmission parameters is a ratio between the power used for data transmission and a power used for transmission of a control signal. 
     
     
       31. The device as claimed in  claim 22 , wherein the a relevant property of a second signal is its value compared to a value of the first transmission parameter in the first preceding TTI. 
     
     
       32. A method of operating a communication system comprising a scheduler and at least one communication device, the method comprising
 the communication device transmitting a first signal with using a transmission parameter, wherein the transmission parameter is selected from a group consisting of: a power and a rate, 
 adapting, in response to receiving a second signal generated by the scheduler, the transmission parameter of the first signal in accordance with a value indicated by a second signal, and 
 adapting, in response to receiving a third signal generated by the scheduler, the transmission parameter of the first signal relative to a reference value, the method further comprising 
 the communication device selecting the reference value one of: a value of a first transmission parameter at a first preceding time instant and a value of a second transmission parameter at a second preceding time instant, the selection being dependent on a property of at least one of the second and third signals. 
 
     
     
       33. The method as claimed in  claim 32 , in which the first signal comprises data transmitted in groups of transmission time intervals (TTI), wherein the first preceding time instant is a first preceding TTI and the second preceding time instant is a second preceding TTI. 
     
     
       34. The method as claimed in  claim 33 , wherein the first preceding TTI is a correspondingly numbered TTI in the preceding group of TTIs. 
     
     
       35. The method as claimed in  claim 32 , wherein at least one of the first and second transmission parameters is a power available to transmit data. 
     
     
       36. The method as claimed in  claim 32 , wherein at least one of the first and second transmission parameters is a rate available for data transmission. 
     
     
       37. The method as claimed in  claim 32 , wherein at least one of the first and second transmission parameters is a ratio between a power available for data transmission and a power used for transmission of a control signal. 
     
     
       38. The method as claimed in  claim 32 , wherein at least one of the first and second transmission parameters is a power used for data transmission. 
     
     
       39. The method as claimed in  claim 32 , wherein at least one of the first and second transmission parameters is a rate used for data transmission. 
     
     
       40. The method as claimed in  claim 32 , wherein at least one of the first and second transmission parameters is a ratio between the power used for data transmission and a power used for transmission of a control signal. 
     
     
       41. The method as claimed in  claim 32 , wherein the a relevant property of a second signal is its value compared to a value of the first transmission parameter in the first preceding TTI. 
     
     
       42. A communication system comprising a scheduler for generating second and third signals and a communication device as claimed in  claim 22 . 
     
     
       43. A method of operating a communication system comprising a scheduler and a user equipment, the method comprising:
 providing a the scheduler including a processor operating in accordance with program software for controlling the user equipment in a service area by sending control transmissions on one or more scheduling channels; and 
 controlling the user equipment with combinations of absolute (AG) and relative (RG) grants, 
 wherein a priority given to the absolute grants or the relative grants is dependent on a property of one or more of the respective absolute grant or the relative grant; and 
 at least one transmission parameter of a next transmission frame is determined based on the priority of the grant and the at least one transmission parameter in a preceding transmission frame, said at least one transmission parameter of the next transmission frame being selected from a group consisting of: a power and a rate; 
 wherein the at least one transmission parameter of a next transmission frame is determined by selecting the lower of a second transmission parameter and a third transmission parameter. 
 
     
     
       44. The method as claimed in  claim 43 , wherein in response to a user equipment receiving a relative grant and an absolute grant both applicable to a same transmission time interval, the user equipment selects one of the received relative grant and absolute grant depending upon whether the absolute grant is all-process or single process. 
     
     
       45. The method as claimed in  claim 43 , wherein in response to a user equipment receiving a relative grant and an absolute grant both applicable to a same transmission time interval, the user equipment selects one of the received relative grant and absolute grant depending upon which is the lower or higher of the received relative grant and absolute grant. 
     
     
       46. Software A non-transitory computer readable medium comprising instructions executable by a processor for controlling the operation of a communication system in accordance with the method as claimed in  claim 43  comprising a scheduler and a user equipment, the instructions when executed:
 providing the scheduler including a processor operating in accordance with program software for controlling the user equipment in a service area by sending control transmissions on one or more scheduling channels; and 
 controlling the user equipment with combinations of absolute (AG) and relative (RG) grants, wherein a priority given to the absolute grants or the relative grants is dependent on a property of one or more of the respective absolute grant or the relative grant; and at least one transmission parameter of a next transmission frame is determined based on the priority of the grant and the at least one transmission parameter in a preceding transmission frame, said transmission parameter being selected from a group consisting of: a power and a rate. 
 
     
     
       47. A communication device comprising
 a transmitter configured to transmit a first signal using a transmission parameter, wherein the transmission parameter is selected from a group consisting of: a power and a rate,   a computer processor configured to adapt, in response to receiving a second signal, the transmission parameter of the first signal in accordance with a value indicated by the second signal and for adapting, in response to a third signal, the transmission parameter of the first signal relative to a reference value,   the computer processor further configured to select, based on a property of at least one of the second and third signals, the reference value from one of: a value of a first transmission parameter at a first preceding time instant and a value of a second transmission parameter at a second preceding time instant.   
     
     
       48. The communication device as claimed in claim 47, wherein the computer processor is a microcontroller. 
     
     
       49. The communication device as claimed in claim 47, in which the first signal comprises data transmitted in groups of transmission time intervals (TTI), wherein the first preceding time instant is a first preceding TTI and the second preceding time instant is a second preceding TTI. 
     
     
       50. The device as claimed in claim 47, wherein at least one of the first and second transmission parameters is a power available to transmit data. 
     
     
       51. The device as claimed in claim 47, wherein at least one of the first and second transmission parameters is a rate available for data transmission. 
     
     
       52. The device as claimed in claim 47, wherein at least one of the first and second transmission parameters is a ratio between a power available for data transmission and a power used for transmission of a control signal. 
     
     
       53. The device as claimed in claim 47, wherein at least one of the first and second transmission parameters is a power used for data transmission. 
     
     
       54. The device as claimed in claim 47, wherein at least one of the first and second transmission parameters is a rate used for data transmission. 
     
     
       55. The device as claimed in claim 47, wherein at least one of the first and second transmission parameters is a ratio between the power used for data transmission and a power used for transmission of a control signal. 
     
     
       56. The device as claimed in claim 47, wherein a property of the second signal is its value compared to a value of the first transmission parameter in the first preceding TTI. 
     
     
       57. A communication device, comprising:
 a transmitter configured to transmit a first signal based on a first transmission parameter, the first transmission parameter being indicative of a ratio between the power used for data transmission and the power used for transmission of a control signal;   a receiver configured to receive a first grant and a second grant, wherein the first grant indicates a change of the first transmission parameter to a second transmission parameter, and wherein the second grant indicates a change of the first transmission parameter to a third transmission parameter, wherein the first grant is an Absolute Grant (AG) and wherein the second grant is a Relative Grant (RG); and   a computer processor configured to change the first transmission parameter to an updated transmission parameter by selecting the lower of the second transmission parameter and the third transmission parameter, and   wherein the change of the first transmission parameter is relative to a reference value, the reference value being from one of: a value of the first transmission parameter at a first preceding time instant and a value of the second transmission parameter at a second preceding time instant,   wherein the transmitter is configured to transmit a second signal using the updated transmission parameter.   
     
     
       58. The communication device according to claim 57, further comprising a memory, wherein the first transmission parameter of the first signal is set according to a Serving Grant (SG) variable stored in the memory. 
     
     
       59. The communication device according to claim 57, wherein the Relative Grant (RG) indicates an incremental or decremental change to the value of the first transmission parameter to derive the third transmission parameter, and wherein the Absolute Grant (AG) indicates the absolute value of the second transmission parameter. 
     
     
       60. The communication device according to claim 59, wherein the computer processor is further configured to determine if the Absolute Grant is an all-process grant or a single-process grant. 
     
     
       61. The communication device according to claim 57, wherein the first grant and the second grant are applicable to a same transmission time interval (TTI). 
     
     
       62. The communication device according to claim 57, wherein the computer processor is a microcontroller, wherein the transmitter is a radio transmitter, and wherein the receiver is a radio receiver. 
     
     
       63. A method of communicating between a secondary station and a primary station in a communication system, the method comprising:
 transmitting a first signal based on a first transmission parameter, the first transmission parameter being indicative of a ratio between the power used for data transmission and the power used for transmission of a control signal;   receiving a first grant and a second grant, wherein the first grant indicates a change of the first transmission parameter to a second transmission parameter, wherein the second grant indicates a change of the first transmission parameter to a third transmission parameter, wherein the first grant is an Absolute Grant (AG), and wherein the second grant is a Relative Grant (RG);   changing the first transmission parameter to an updated transmission parameter by selecting the lower of the second transmission parameter and the third transmission parameter;   wherein the change of the first transmission parameter is relative to a reference value, the reference value being from one of: a value of the first transmission parameter at a first preceding time instant and a value of the second transmission parameter at a second preceding time instant, and   transmitting a second signal using the updated transmission parameter.   
     
     
       64. The method of claim 63, wherein the Relative Grant (RG) indicates an incremental or decremental change to the value of the first transmission parameter to derive the third transmission parameter, and wherein the Absolute Grant (AG) indicates the absolute value of the second transmission parameter. 
     
     
       65. The method of claim 63, wherein the first grant and the second grant are applicable to a same transmission time interval (TTI). 
     
     
       66. A non-transitory computer readable medium having stored thereon instructions that cause computer processing circuitry to:
 transmit a first signal based on a first transmission parameter, the first transmission parameter being indicative of a ratio between the power used for data transmission and the power used for transmission of a control signal;   receive a first grant and a second grant, wherein the first grant indicates a change of the first transmission parameter to a second transmission parameter, wherein the second grant indicates a change of the first transmission parameter to a third transmission parameter, wherein the first grant is an Absolute Grant (AG), and wherein the second grant is a Relative Grant (RG);   change the first transmission parameter to an updated transmission parameter by selecting the lower of the second transmission parameter and the third transmission parameter;   wherein the change of the first transmission parameter is relative to a reference value, the reference value being from one of: a value of the first transmission parameter at a first preceding time instant and a value of the second transmission parameter at a second preceding time instant, and   transmit a second signal using the updated transmission parameter.   
     
     
       67. The non-transitory computer-readable medium of claim 66, wherein the Relative Grant (RG) indicates an incremental or decremental change to the value of the first transmission parameter to derive the third transmission parameter, and wherein the Absolute Grant (AG) indicates the absolute value of the second transmission parameter. 
     
     
       68. The non-transitory computer-readable medium of claim 66, wherein the first grant and the second grant are applicable to a same transmission time interval (TTI).