Method and apparatus for uplink power control in communication system
Disclosed is a method for uplink power control in a communication system that includes determining a power control offset for controlling power for traffic to be transmitted by a subscriber station, according to whether a Hybrid Automatic Repeat reQuest (HARQ) is applied to the traffic, and transmitting the power control offset to the subscriber station.
1. A method for uplink power control by a base station in a communication system, the method comprising the steps of:
determining a relative power offset for controlling power for traffic to be transmitted by a subscriber station, for a Hybrid Automatic Repeat reQuest (HARQ) burst relative to a non-HARQ burst; and
transmitting the relative power offset to the subscriber station,
wherein the relative power offset is usable to require the subscriber station to adjust an UpLink (UL) transmission power of the HARQ burst by adding the relative power offset to a carrier-to-noise ratio value of the non-HARQ burst,
wherein the relative power offset is contained in a format of a TLV (Type, Length, and Value) in an Uplink Channel Descriptor (UCD) message, and
wherein the relative power offset is used for determining the UL transmission power of the HARQ burst by using a UL path loss and a noise and interference Power Spectral Density (PSD).
2. The method as claimed in claim 1 , wherein the relative power offset is used for determining a transmission power according to
P=PL+CINR+NI+ 10 log 10 ( BW ) +E
where P represents the UL transmission power of the HARQ burst, PL represents the UL path loss, CINR represents a target carrier-to-noise ratio value of the non-HARQ burst, NI represents the noise and interference PSD, BW represents an allocated bandwidth, and E represents the relative power offset.
3. The method as claimed in claim 1 , wherein the relative power offset is determined to be a value for controlling a UL transmission power for the HARQ burst to have a power level greater than a power level of a UL transmission power for the non-HARQ burst.
4. The method as claimed in claim 3 , wherein the relative power offset is determined to be a value corresponding to a difference between target Packet Error Rates (PERs) required for the HARQ burst and the non-HARQ burst.
5. A method for uplink power control by a subscriber station in a communication system, the method comprising the steps of:
receiving a relative power offset, for controlling transmission power of traffic, for a Hybrid Automatic Repeat reQuest (HARQ) burst relative to a non-HARQ burst, from a base station; and
setting an UpLink (UL) transmission power for a HARQ burst responsive to the relative power offset,
wherein the relative power offset is usable to require the subscriber station to adjust an UL transmission power of the HARQ burst by adding the relative power offset to a carrier-to-noise ratio value of the non-HARQ burst,
wherein the relative power offset is contained in a format of a TLV (Type, Length, and Value) in an Uplink Channel Descriptor (UCD) message, and
wherein the relative power offset is used for determining the UL transmission power of the HARQ burst by using a UL path loss and a noise and interference Power Spectral Density (PSD).
6. The method as claimed in claim 5 , wherein the relative power offset is received in the UCD message corresponding to a value determined by a difference between target Packet Error Rates (PERs) required for the HARQ burst and the non-HARQ burst.
7. The method as claimed in claim 5 , wherein the setting step further comprises setting the UL transmission power for the HARQ burst to have a power level greater than a UL transmission power for the non-HARQ burst by means of the relative power offset.
8. The method as claimed in claim 5 , wherein the relative power offset is determined to be a value corresponding to a difference between target Packet Error Rates (PERs) required for the HARQ burst and the non-HARQ burst.
9. A base station for controlling uplink power of a subscriber station in a communication system, wherein:
the base station determines a relative power offset for controlling power of traffic to be transmitted by the subscriber station, for a Hybrid Automatic Repeat reQuest (HARQ) burst relative to a non-HARQ burst and transmits the relative power offset to the subscriber station,
wherein the relative power offset is usable to require the subscriber station to adjust an UpLink (UL) transmission power of the HARQ burst by adding the relative power offset to a carrier-to-noise ratio value of the non-HARQ burst,
wherein the relative power offset is contained in a format of a TLV (Type, Length, and Value) in an Uplink Channel Descriptor (UCD) message, and
wherein the relative power offset is used for determining the UL transmission power of the HARQ burst by using a UL path loss and a noise and interference Power Spectral Density (PSD).
10. The base station as claimed in claim 9 , wherein the relative power offset is determined by a value for controlling a UL transmission power for the HARQ burst to have a power level greater than a UL transmission power for the non-HARQ burst.
11. The base station as claimed in claim 10 , wherein the power control offset is determined by a difference between target Packet Error Rates (PERs) required for the HARQ burst and the non-HARQ burst.
12. A subscriber station for controlling uplink power in a communication system, wherein the subscriber station receives, from a base station, a relative power offset for controlling transmission power of traffic to be transmitted by the subscriber station, for a Hybrid Automatic Repeat reQuest (HARQ) burst relative to a non-HARQ burst and set an uplink (UL) transmission power for the HARQ burst responsive to the relative power offset,
wherein the relative power offset is usable to require the subscriber station to adjust the UL transmission power of the HARQ burst by adding the relative power offset to a carrier-to-noise ratio value of the non-HARQ burst,
wherein the relative power offset is contained in a format of a TLV (Type, Length, and Value) in an Uplink Channel Descriptor (UCD) message, and
wherein the relative power offset is used for determining the UL transmission power of the HARQ burst by using a UL path loss and a noise and interference Power Spectral Density (PSD).
13. The subscriber station as claimed in claim 12 , wherein the subscriber station sets the UL transmission power for the HARQ burst to have a power level greater than the UL transmission power for the non-HARQ traffic by means of the relative power offset.
14. The subscriber station as claimed in claim 12 , wherein the relative power offset is determined to be a value corresponding to a difference between target Packet Error Rates (PERs) required for the HARQ burst and the non-HARQ burst.
15. The method as claimed in claim 1 , wherein the UCD message comprises the carrier-to-noise ratio value for the non-HARQ burst.
16. The method as claimed in claim 5 , wherein the UCD message comprises the carrier-to-noise ratio value for the non-HARQ burst.
17. The method as claimed in claim 5 , wherein the relative power offset is used for determining the UL transmission power based on
P=PL+CINR+NI+ 10 log 10 ( BW ) +E
where P represents the UL transmission power of the HARQ burst, PL represents the UL path loss, CINR represents a target carrier-to-noise ratio value of the non-HARQ burst, NI represents the noise and interference PSD BW represents an allocated bandwidth, and E represents the relative power offset.
18. The base station of claim 9 , wherein the relative power offset is used for determining an uplink, UL, transmission power based on
P=PL+CINR+NI+ 10 log 10 ( BW ) +E
where P represents the UL transmission power of the HARQ burst, PL represents the UL path loss, CINR represents a target carrier-to-noise ratio value of the non-HARQ burst, NI represents the noise and interference PSD BW represents an allocated bandwidth and E represents the relative power offset.
19. The base station as claimed in claim 9 , wherein the UCD message comprises the carrier-to-noise ratio value, value for the non-HARQ burst.
20. The subscriber station as claimed in claim 12 , wherein the UCD message comprises the carrier-to-noise ratio value for the non-HARQ burst.
21. The subscriber station as claimed in claim 12 , wherein the relative power offset is used for determining the UL transmission power according to
P=PL+CINR+NI+ 10 log 10 ( BW ) +E,
where P represents the UL transmission power of the HARQ burst, PL represents the UL path loss, CINR represents a target carrier-to-noise ratio value of the non-HARQ burst, NI represents the noise and interference PSD BW represents an allocated bandwidth and E represents the relative power offset.