METHOD AND CORRESPONDING APPARATUS FOR POWER CONTROL
According to the exemplary embodiments of the present invention, a wireless access point apparatus in a multi-point coordination system of a heterogeneous network obtains all pathlosses of all coordination micro wireless access points in a coordination set of a user equipment; obtains a real pathlosss from the user equipment to a macro wireless access point; calculates a virtual pathloss from a virtual user equipment corresponding to the user equipment to the macro wireless access point based on the obtained respective pathloss and; and informs the user equipment of information related to the computed virtual pathloss. A user equipment in a multi-point coordination system of a heterogeneous network receives information related to a virtual pathloss from a wireless access point acting as a scheduling network element; and performs power control using an uplink open-loop power control parameter for a macro wireless access point based on the information related to the virtual pathloss.
1 . A method for operating a wireless access point apparatus in a multi-point coordination system of a heterogeneous network, comprising:
obtaining all pathlosses PL 1 , . . . , PL n of all coordination pico wireless access points in a coordination set of a user equipment;
obtaining a real pathlosss PL 0 from the user equipment to a macro wireless access point;
calculating a virtual pathloss PL′ 0 from a virtual user equipment corresponding to the user equipment to the macro wireless access point based on the obtained respective pathlosses PL 0 and PL 1 , . . . , PL n ;
informing the user equipment of information related to the calculated virtual pathloss PL′ 0 .
2 .- 4 . (canceled)
5 . The method according to claim 1 , wherein the virtual pathloss PL′ 0 may be expressed as:
PL′ 0 =ƒ( PL 0 ,PL 1 , . . . PL n )
wherein the function ƒ(·) is dependent on a specific multi-point coordination processing algorithm for the user equipment in the multi-point coordination system.
6 . The method according to claim 1 , wherein the calculating step further comprises:
calculating a relative value between a virtual pathloss PL′ 0 and a real pathlosss PL 0 ;
wherein the information related to the calculated virtual pathloss PL′ 0 includes the relative value.
7 . The method according to claim 6 , wherein the relative value comprises a value β representing a ratio relationship between the real pathloss PL 0 and the virtual pathloss PL′ 0 .
8 . The method according to claim 7 , further comprising: calculating, based on the value β representing a ratio relationship between the real pathloss PL 0 and the virtual pathloss PL′ 0 , a virtual UE-specific offset component P 0U ′=P 0U +α·(β−1)·PL 0 of a base level P 0 , wherein α denotes a pathloss compensation factor,
wherein the virtual UE-specific offset component P 0U ′ is informed to the user equipment via a higher-layer signaling.
9 . The method according to claim 7 , further comprising: calculating, based on the β value representing a ratio relationship between the real pathloss PL 0 and the virtual pathloss PL′ 0 , a virtual closed-loop power control correction value δ′=δ+α·(β−1)PL 0 , wherein α denotes a pathloss compensation factor,
wherein the virtual closed-loop power control correction value δ′ is informed to the user equipment via a dynamic signaling.
10 . The method according to claim 6 , wherein the relative value comprises a value Δ representing a difference relationship between the real pathloss PL 0 and the virtual pathloss PL′ 0 .
11 . The method according to claim 10 , further comprising: calculating, based on the value Δ representing a difference relationship between the real pathloss PL 0 and the virtual pathloss PL′ O , a virtual UE-specific offset component P 0U ′=P 0U +α·Δ of a base level P 0 , wherein α denotes a pathloss compensation factor,
wherein the virtual UE-specific offset component P 0U ′ is informed to the user equipment via a higher-layer signaling.
12 . The method according to claim 10 , further comprising calculating, based on the value β representing a ratio relationship between the real pathloss PL 0 and the virtual pathloss PL′ O , a virtual closed-loop power control correction value δ′=δ+α·Δ, wherein α denotes a pathloss compensation factor,
wherein the virtual closed-loop power control correction value δ′ is informed to the user equipment via a dynamic signaling.
13 .- 23 . (canceled)
24 . A wireless access point apparatus in a multi-point coordination system of a heterogeneous network, comprising:
an obtaining module for obtaining all pathlosses PL 1 , . . . , PL n of all coordination pico wireless access points in a coordination set of a user equipment and obtaining a real pathlosss PL 0 from the user equipment to a macro wireless access point;
a calculating module for calculating a virtual pathloss PL′ 0 from a virtual user equipment corresponding to the user equipment to the macro wireless access point based on the obtained respective pathlosses PL 0 and PL 1 , . . . , PL n ;
an informing module for informing the user equipment of information related to the calculated virtual pathloss PL′ 0 .
25 .- 27 . (canceled)
28 . The wireless access point apparatus according to claim 24 , wherein the virtual pathloss PL′ 0 may be expressed as:
PL′ 0 =ƒ( PL O ,PL 1 , . . . PL n )
wherein the function ƒ(·) is dependent on a specific multi-point coordination processing algorithm for the user equipment in the multi-point coordination system.
29 . The wireless access point apparatus according to claim 24 , wherein the calculating module is further configured to calculate a relative value between a virtual pathloss PL′ 0 and a real pathlosss PL 0 ;
wherein the informing module is configured to inform the user equipment of the relative value.
30 . The wireless access point apparatus according to claim 29 , wherein the relative value comprises a value β representing a ratio relationship between the real pathloss PL 0 and the virtual pathloss PL′ 0 .
31 .- 32 . (canceled)
33 . The wireless access point apparatus according to claim 29 , wherein the relative value comprises a value Δ representing a difference relationship between the real pathloss PL 0 and the virtual pathloss PL′ 0 .
34 .- 35 . (canceled)
36 . A user equipment in a multi-point coordination system of a heterogeneous network, comprising:
a receiving module for receiving information related to a virtual pathloss PL′ 0 from a wireless access point acting as a scheduling network element;
a power control module for performing power control using uplink open-loop power control parameters for a macro wireless access point based on the information related to the virtual pathloss PL′ 0 .
37 .- 47 . (canceled)