CN104619032B

CN104619032B - Method and apparatus for transmitting and acquiring power headroom report

Info

Publication number: CN104619032B
Application number: CN201310544972.2A
Authority: CN
Inventors: 孙芳蕾; 杨涛; 叶思根; 马修·贝克; 郑方政
Original assignee: Alcatel Lucent SAS
Current assignee: Alcatel Lucent SAS
Priority date: 2013-11-05
Filing date: 2013-11-05
Publication date: 2020-05-26
Anticipated expiration: 2033-11-05
Also published as: WO2015068039A2; WO2015068039A3; CN104619032A

Abstract

The embodiment of the invention provides a method and a device for transmitting and acquiring PHR in a TDD system, wherein the TDD system is configured with a first UL subframe set and a second UL subframe set. The sending method comprises the following steps: in response to a predetermined trigger condition being met for both the first and second sets of UL subframes, determining a PHR for at least one of the first and second sets of UL subframes; and transmitting an information block to the base station, the information block including the determined PHR and an implicit UL subframe set indication and/or an explicit UL subframe set indication for indicating that the determined PHR is for the first or second UL subframe set. By utilizing the scheme provided by the invention, the UE can provide the PHR aiming at one of the first and second UL subframe sets or the PHR aiming at both the first and second UL subframe sets for the base station, thereby realizing the accurate scheduling of the base station on the UE on different UL subframe sets.

Description

Method and apparatus for transmitting and acquiring power headroom report

Technical Field

Embodiments of the present invention relate generally to communication technology and, more particularly, relate to a method and apparatus for transmitting and acquiring a Power Headroom Report (PHR) in a Time Division Duplex (TDD) system.

Background

In wireless communication systems, power control is a critical technique. Currently, power control, including open-loop and closed-loop, is performed at a User Equipment (UE). Based on such power control, the user equipment needs to send a power headroom report to the base station, and the base station derives from the received power headroom report the Power Spectral Density (PSD) used by the Physical Uplink Shared Channel (PUSCH) at the user equipment and the remaining power headroom. Then, using the derived power spectral density and the remaining power margin, the base station can determine how many Resource Units (RUs) to allocate to the user equipment and the Modulation and Coding Scheme (MCS) suitable for use by the user equipment to ensure that a desired signal to interference and noise ratio (SINR) is obtained on the radio link between the user equipment and the base station.

In a TDD system, there are seven different Uplink (UL) -Downlink (DL) configurations, i.e., configurations 0 to 6 as shown in table 1 below.

TABLE 1

As shown in table 1, the TDD radio frame includes 10 subframes with indices of 0 and 1. Each subframe may be used for DL transmission or UL transmission, or as a special subframe between a DL period and a UL period. Taking configuration 0 as an example, subframes with indices of 0 and 5 are used for DL transmission, and thus are denoted by "D"; subframes with indices of 2 to 4 and 7 to 9 are used for UL transmission and thus denoted by "U", and subframes with indices of 1 and 6 are used as special subframes and thus denoted by "S".

Further, all or part of UL subframes in a radio frame may be divided into at most two UL subframe sets according to the degree of interference by neighboring base stations. Taking configuration 0 in table 1 as an example, the first UL subframe set may include subframe 2 in configuration 0, and the second UL subframe set may include subframes 3, 4, 7, 8, and 9 in configuration 0.

For PHR, since UL subframes in different UL subframe sets suffer different degrees of DL interference from neighboring base stations, different open-loop operating points and different closed-loop power adjustment amounts for one step should be adopted for different UL subframe sets, which results in that PHR for different UL subframe sets should be different. However, in the current communication specification, only PHR for one UL subframe set is considered. Therefore, how to feed back PHR for one or both UL subframe sets to the base station in the TDD system remains an open issue.

Disclosure of Invention

Embodiments of the present invention propose a scheme for transmitting and acquiring a PHR in a TDD system to solve or at least partially alleviate at least part of the problems of the prior art.

According to a first aspect of embodiments of the present invention, there is provided a method for transmitting a Power Headroom Report (PHR) in a Time Division Duplex (TDD) system configured with a first set of Uplink (UL) subframes and a second set of UL subframes. The method may comprise: determining a PHR for at least one of the first and second sets of UL subframes in response to a predetermined trigger condition being met for both the first and second sets of UL subframes; and transmitting an information block to a base station, the information block including the determined PHR and an implicit UL subframe set indication and/or an explicit UL subframe set indication indicating that the determined PHR is for the first UL subframe set or the second UL subframe set.

In one exemplary embodiment, one of a first PHR for the first UL subframe set and a second PHR for the second UL subframe set is determined in response to one trigger condition predetermined for both the first UL subframe set and the second UL subframe set being satisfied.

In an example embodiment, in response to one trigger condition predetermined for both the first and second sets of UL subframes being met, determining a first PHR for the first set of UL subframes and a second PHR for the second set of UL subframes, respectively; and wherein an information block including both the first PHR and the second PHR is transmitted.

In an example embodiment, in response to one trigger condition predetermined for both the first and second sets of UL subframes being met, determining a first PHR for the first set of UL subframes and a second PHR for the second set of UL subframes, respectively; and wherein a first information block including the first PHR and a second information block including the second PHR are transmitted, respectively.

In one exemplary embodiment, a first PHR for the first UL subframe set is determined in response to a first trigger condition predetermined for the first UL subframe set being satisfied, and a second PHR for the second UL subframe set is determined in response to a second trigger condition predetermined for the second UL subframe set being satisfied; and wherein a first information block including the first PHR and a second information block including the second PHR are transmitted, respectively.

In one exemplary embodiment, a first PHR for the first UL subframe set is determined in response to a first trigger condition predetermined for the first UL subframe set being satisfied, and a second PHR for the second UL subframe set is determined in response to a second trigger condition predetermined for the second UL subframe set being satisfied; and wherein an information block including both the first PHR and the second PHR is transmitted.

In one exemplary embodiment, the one of the first and second PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power; and wherein an information block including the one of the first PHR and the second PHR is transmitted on one scheduled UL subframe immediately following a triggering UL or DL subframe on which the triggering condition is satisfied, the scheduled UL subframe belonging to one of the first UL subframe set and the second UL subframe set.

In one exemplary embodiment, the one of the first and second PHR is determined based on a hypothetical reference format corresponding to a respective one of the first and second UL subframe sets; and transmitting an information block including the one of the first and second PHRs on a first UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied, the first UL subframe belonging to a UL subframe set for which a PHR is determined among the first and second UL subframe sets.

In one exemplary embodiment, both the first PHR and the second PHR are determined based on a maximum transmission power and a pre-allocated UL transmission power; and transmitting an information block including both the first PHR and the second PHR on a later scheduled UL subframe among a first scheduled UL subframe belonging to the first UL subframe set and a second scheduled UL subframe belonging to the second UL subframe set, the later scheduled UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied.

In one exemplary embodiment, one of the first and second PHRs is determined based on a maximum transmission power and a pre-allocated UL transmission power, and the other of the first and second PHRs is determined based on a hypothetical reference format corresponding to the respective one of the first and second sets of UL subframes; and transmitting an information block including both the first PHR and the second PHR on one scheduled UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied, the scheduled UL subframe belonging to one of the first UL subframe set and the second UL subframe set.

In one exemplary embodiment, both the first PHR and the second PHR are determined based on a hypothetical reference format corresponding to a respective one of the first UL subframe set and the second UL subframe set, respectively; and transmitting an information block including both the first PHR and the second PHR on a first UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied, the first UL subframe belonging to one of the first UL subframe set and the second UL subframe set.

In one exemplary embodiment, both the first PHR and the second PHR are determined based on a maximum transmission power and a pre-allocated UL transmission power; and transmitting a first information block including the first PHR on a first scheduled UL subframe and a second information block including the second PHR on a second scheduled UL subframe, respectively, the first scheduled UL subframe immediately following a first triggered UL or DL subframe on which a corresponding trigger condition is satisfied, and the second scheduled UL subframe immediately following a second triggered UL or DL subframe on which a corresponding trigger condition is satisfied.

In one exemplary embodiment, the first PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power, and the second PHR is determined based on a hypothetical reference format corresponding to the second UL subframe set; transmitting the first information block including the first PHR on a scheduled UL subframe immediately following one UL or DL subframe on which the trigger condition is satisfied, the scheduled UL subframe belonging to the first UL subframe set; and transmitting the second information block including the second PHR on a first UL subframe immediately following the one UL or DL subframe on which the trigger condition is satisfied, the first UL subframe belonging to the second UL subframe set.

In one exemplary embodiment, both the first PHR and the second PHR are determined based on a hypothetical reference format corresponding to a respective one of the first UL subframe set and the second UL subframe set, respectively; and transmitting the first information block including the first PHR on a first UL subframe immediately following a first trigger UL or DL subframe on which a corresponding trigger condition is satisfied, and transmitting the second information block including the second PHR on a first UL subframe immediately following a second trigger UL or DL subframe on which a corresponding trigger condition is satisfied, respectively.

In one exemplary embodiment, the information block is transmitted via a PHR control unit.

In an example embodiment, the PHR control element includes a payload portion including the first PHR, the second PHR, a first reserved field carrying the display UL subframe set indication, and/or a second reserved field carrying a power headroom calculation indication specifying whether the first or second PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power or a hypothetical reference format corresponding to the respective one of the first and second UL subframe sets.

In one exemplary embodiment, the PHR control unit includes: a first data portion comprising the first PHR; a third reserved field associated with the first data portion for carrying a power headroom calculation indication for the first set of UL subframes, the power headroom calculation indication for the first set of UL subframes specifying whether the first PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power or a hypothetical reference format corresponding to the first set of UL subframes; a second data portion comprising the second PHR; and a fourth reserved field associated with the second data portion for carrying a power headroom calculation indication for the second set of UL subframes, the power headroom calculation indication for the second set of UL subframes specifying whether the second PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power or a hypothetical reference format corresponding to the second set of UL subframes.

In an exemplary embodiment, the PHR control element further comprises a fifth reserved field associated with the first data portion for carrying an explicit UL subframe set indication for the first UL subframe set and/or a sixth reserved field associated with the second data portion for carrying an explicit UL subframe set indication for the second UL subframe set.

In an exemplary embodiment, the first data portion and the third reserved field, and the second data portion and the fourth reserved field are arranged in the PHR control unit in a predetermined order.

In an exemplary embodiment, the predetermined order comprises one of: the first data portion and the third reserved field associated therewith precede the second data portion and the fourth reserved field associated therewith; and the second data portion and the fourth reserved field associated therewith precede the first data portion and the third reserved field associated therewith.

In one exemplary embodiment, each of the first information block and the second information block is transmitted via a PHR control unit.

In one example embodiment, the PHR control element includes a payload portion including the first or second PHR, and a seventh reserved field carrying the explicit UL subframe set indication and/or an eighth reserved field carrying a power headroom calculation indication indicating whether the first or second PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power or a hypothetical reference format corresponding to the respective one of the first and second UL subframe sets.

In one exemplary embodiment, a carrier aggregation user of the TDD system is configured to support up to five component carriers; wherein for each of the at most five component carriers, in response to a predetermined trigger condition being met for both the first and second sets of UL subframes, determining a respective PHR for at least one of the first and second sets of UL subframes; and transmitting an information block including the PHR on a corresponding one of the at most five component carriers.

In one exemplary embodiment, the information block is transmitted via a PHR control unit supporting the at most five component carriers.

In one example embodiment, the PHR control element supporting the at most five component carriers comprises a component carrier indication and the display UL subframe set indication indicating power with the component carrier, the display UL subframe set indication indicating whether the determined PHR for the respective component carrier is for the first UL subframe set or the second UL subframe set.

In one exemplary embodiment, the implicit UL subframe set indication includes an index of a UL subframe on which the information block is transmitted.

According to a second aspect of embodiments of the present invention, there is provided a method for acquiring a Power Headroom Report (PHR) in a Time Division Duplex (TDD) system configured with a first set of Uplink (UL) subframes and a second set of UL subframes. The method may comprise: receiving an information block from a user equipment, the information block comprising a PHR determined for at least one of the first and second sets of UL subframes in response to a predetermined trigger condition being met for both the first and second sets of UL subframes, and an implicit UL subframe set indication and/or an explicit UL subframe set indication for indicating the determined PHR for the first or second set of UL subframes; and parsing the information block to obtain a PHR of the user equipment for at least one of the first UL subframe set and the second UL subframe set.

In one exemplary embodiment, a first PHR for the first UL subframe set and a second PHR for the second UL subframe set are respectively determined in response to satisfying one trigger condition predetermined for both the first UL subframe set and the second UL subframe set; and receiving an information block including both the first PHR and the second PHR.

In one exemplary embodiment, a first PHR for the first UL subframe set and a second PHR for the second UL subframe set are respectively determined in response to satisfying one trigger condition predetermined for both the first UL subframe set and the second UL subframe set; and receiving a first information block including the first PHR and a second information block including the second PHR, respectively.

In one exemplary embodiment, a first PHR for the first UL subframe set is determined in response to satisfying a first trigger condition predetermined for the first UL subframe set, and a second PHR for the second UL subframe set is determined in response to satisfying a second trigger condition predetermined for the second UL subframe set; and receiving a first information block including the first PHR and a second information block including the second PHR, respectively.

In one exemplary embodiment, a first PHR for the first UL subframe set is determined in response to satisfying a first trigger condition predetermined for the first UL subframe set, and a second PHR for the second UL subframe set is determined in response to satisfying a second trigger condition predetermined for the second UL subframe set; and receiving an information block including both the first PHR and the second PHR.

In one exemplary embodiment, the one of the first and second PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power; and receiving an information block including the one of the first and second PHRs on one scheduled UL subframe immediately following a triggering UL or DL subframe on which the triggering condition is satisfied, the scheduled UL subframe belonging to one of the first and second UL subframe sets.

In one exemplary embodiment, the one of the first and second PHR is determined based on a hypothetical reference format corresponding to the respective one of the first and second UL subframe sets; and receiving an information block including the one of the first and second PHRs on a first UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied, the first UL subframe belonging to a UL subframe set for which a PHR is determined among the first and second UL subframe sets.

In one exemplary embodiment, both the first PHR and the second PHR are determined based on a maximum transmission power and a pre-allocated UL transmission power; and receiving an information block including both the first PHR and the second PHR on a later scheduled UL subframe among a first scheduled UL subframe belonging to the first UL subframe set and a second scheduled UL subframe belonging to the second UL subframe set, the later scheduled UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied.

In one exemplary embodiment, one of the first and second PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power, and the other of the first and second PHR is determined based on a hypothetical reference format corresponding to the respective one of the first and second UL subframe sets; and receiving an information block including both the first PHR and the second PHR on one scheduled UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied, the scheduled UL subframe belonging to one of the first UL subframe set and the second UL subframe set.

In one exemplary embodiment, both the first PHR and the second PHR are determined based on a hypothetical reference format corresponding to a respective one of the first UL subframe set and the second UL subframe set, respectively; and receiving an information block including both the first PHR and the second PHR on a first UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied, the first UL subframe belonging to one of the first UL subframe set and the second UL subframe set.

In one exemplary embodiment, both the first PHR and the second PHR are determined based on a maximum transmission power and a pre-allocated UL transmission power; and receiving a first information block including the first PHR on a first scheduled UL subframe and a second information block including the second PHR on a second scheduled UL subframe, respectively, the first scheduled UL subframe immediately following a first triggered UL or DL subframe on which a corresponding trigger condition is satisfied, and the second scheduled UL subframe immediately following a second triggered UL or DL subframe on which a corresponding trigger condition is satisfied.

In one exemplary embodiment, the first PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power, and the second PHR is determined based on a hypothetical reference format corresponding to the second UL subframe set; receiving the first information block including the first PHR on a scheduled UL subframe immediately following one UL or DL subframe on which the trigger condition is satisfied, the scheduled UL subframe belonging to the first UL subframe set; and receiving the second information block including the second PHR on a first UL subframe immediately following the one UL or DL subframe on which the trigger condition is satisfied, the first UL subframe belonging to the second UL subframe set.

In one exemplary embodiment, both the first PHR and the second PHR are determined based on a hypothetical reference format corresponding to a respective one of the first UL subframe set and the second UL subframe set, respectively; and receiving the first information block including the first PHR on a first UL subframe immediately following a first trigger UL or DL subframe on which a corresponding trigger condition is satisfied, and receiving the second information block including the second PHR on a first UL subframe immediately following a second trigger UL or DL subframe on which a corresponding trigger condition is satisfied, respectively.

In an exemplary embodiment, the information block is received via a PHR control unit.

In an exemplary embodiment, the predetermined order comprises one of:

the first data portion and the third reserved field associated therewith precede the second data portion and the fourth reserved field associated therewith; and

the second data portion and the fourth reserved field associated therewith precede the first data portion and the third reserved field associated therewith.

In one exemplary embodiment, each of the first information block and the second information block is received via a PHR control unit.

In an example embodiment, the PHR control element includes a payload portion including the first or second PHR, and a seventh reserved field carrying the display UL subframe set indication and/or an eighth reserved field carrying a power headroom calculation indication indicating whether the first or second PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power or a hypothetical reference format corresponding to the respective one of the first and second UL subframe sets.

In one exemplary embodiment, the TDD system is configured to support up to five component carriers; wherein a respective PHR for each of the at most five component carriers for at least one of the first and second sets of UL subframes is determined in response to a predetermined trigger condition being met for both the first and second sets of UL subframes; and wherein an information block comprising the PHR is received on a respective one of the at most five component carriers.

In one exemplary embodiment, the information block is received via a PHR control unit supporting the at most five component carriers.

In one exemplary embodiment, the PHR control element supporting the at most five component carriers includes a component carrier indication and the display UL subframe set indication with the component carrier indication power.

In one exemplary embodiment, the implicit UL subframe set indication includes an index of a UL subframe on which the information block is received.

According to a third aspect of embodiments of the present invention, there is provided an apparatus for transmitting a Power Headroom Report (PHR) in a Time Division Duplex (TDD) system configured with a first set of Uplink (UL) subframes and a second set of UL subframes. The apparatus may comprise: a determining unit configured to determine a PHR for at least one of the first and second sets of UL subframes in response to a predetermined trigger condition being met for both the first and second sets of UL subframes; and a transmitting unit configured to transmit an information block to a base station, the information block including the determined PHR and an implicit UL subframe set indication and/or an explicit UL subframe set indication for indicating the determined PHR for the first UL subframe set or the second UL subframe set.

In an exemplary embodiment, the determining unit is further configured to determine one of a first PHR for the first UL subframe set and a second PHR for the second UL subframe set in response to one trigger condition predetermined for both the first UL subframe set and the second UL subframe set being satisfied.

In an exemplary embodiment, the determining unit is further configured to determine a first PHR for the first UL subframe set and a second PHR for the second UL subframe set, respectively, in response to one trigger condition predetermined for both the first UL subframe set and the second UL subframe set being satisfied; and the transmitting unit is further configured to transmit an information block including both the first PHR and the second PHR.

In an exemplary embodiment, the determining unit is further configured to determine a first PHR for the first UL subframe set and a second PHR for the second UL subframe set, respectively, in response to one trigger condition predetermined for both the first UL subframe set and the second UL subframe set being satisfied; and the transmitting unit is further configured to transmit a first information block including the first PHR and a second information block including the second PHR, respectively.

In one exemplary embodiment, the determining unit is further configured to determine a first PHR for the first UL subframe set in response to satisfying a first trigger condition predetermined for the first UL subframe set, and determine a second PHR for the second UL subframe set in response to satisfying a second trigger condition predetermined for the second UL subframe set; and the transmitting unit is further configured to transmit a first information block including the first PHR and a second information block including the second PHR, respectively.

In one exemplary embodiment, the determining unit is further configured to determine a first PHR for the first UL subframe set in response to satisfying a first trigger condition predetermined for the first UL subframe set, and determine a second PHR for the second UL subframe set in response to satisfying a second trigger condition predetermined for the second UL subframe set; and the manner unit is further configured to transmit an information block including both the first PHR and the second PHR.

In one exemplary embodiment, the determining unit is further configured to determine the one of the first PHR and the second PHR based on a maximum transmission power and a pre-allocated UL transmission power; and the transmitting unit is further configured to wherein the information block including the one of the first PHR and the second PHR is transmitted on one scheduled UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied, the scheduled UL subframe belonging to one of the first UL subframe set and the second UL subframe set.

In one exemplary embodiment, the determining unit is further configured to determine the one of the first PHR and the second PHR based on a hypothetical reference format corresponding to the respective one of the first UL subframe set and the second UL subframe set; and the transmitting unit is further configured to transmit an information block including the one of the first and second PHR on a first UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied, the first UL subframe belonging to a UL subframe set for which a PHR is determined among the first and second UL subframe sets.

In one exemplary embodiment, the determining unit is further configured to determine both the first PHR and the second PHR based on a maximum transmission power and a pre-allocated UL transmission power; and the transmitting unit is further configured to transmit an information block including both the first PHR and the second PHR on a later scheduled UL subframe among a first scheduled UL subframe belonging to the first UL subframe set and a second scheduled UL subframe belonging to the second UL subframe set, the later scheduled UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied.

In one exemplary embodiment, the determining unit is further configured to determine one of the first and second PHR based on a maximum transmission power and a pre-allocated UL transmission power, and determine the other of the first and second PHR based on a hypothetical reference format corresponding to the respective one of the first and second UL subframe sets; and the transmitting unit is further configured to transmit an information block including both the first PHR and the second PHR on one scheduled UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied, the scheduled UL subframe belonging to one of the first UL subframe set and the second UL subframe set.

In one exemplary embodiment, the determining unit is further configured to determine both the first PHR and the second PHR based on a hypothetical reference format corresponding to a respective one of the first UL subframe set and the second UL subframe set, respectively; and the transmitting unit is further configured to transmit an information block including both the first PHR and the second PHR on a first UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied, the first UL subframe belonging to one of the first UL subframe set and the second UL subframe set.

In one exemplary embodiment, the determining unit is further configured to determine both the first PHR and the second PHR based on a maximum transmission power and a pre-allocated UL transmission power; and the transmitting unit is further configured to transmit a first information block including the first PHR on a first scheduled UL subframe and a second information block including the second PHR on a second scheduled UL subframe, respectively, the first scheduled UL subframe immediately following a first triggered UL or DL subframe on which the respective trigger condition is satisfied and the second scheduled UL subframe immediately following a second triggered UL or DL subframe on which the respective trigger condition is satisfied.

In one exemplary embodiment, the determining unit is further configured to determine the first PHR based on a maximum transmission power and a pre-allocated UL transmission power, and determine the second PHR based on a hypothetical reference format corresponding to the second UL subframe set; wherein the transmitting unit is further configured to transmit the first information block including the first PHR on a scheduled UL subframe immediately following one UL or DL subframe on which the trigger condition is satisfied, the scheduled UL subframe belonging to the first UL subframe set; and the transmitting unit is further configured to transmit the second information block including the second PHR on a first UL subframe immediately following the one UL or DL subframe on which the trigger condition is satisfied, the first UL subframe belonging to the second UL subframe set.

In one exemplary embodiment, the determining unit is further configured to determine both the first PHR and the second PHR based on a hypothetical reference format corresponding to a respective one of the first UL subframe set and the second UL subframe set, respectively; and the transmitting unit is further configured to transmit the first information block including the first PHR on a first UL subframe immediately following a first trigger UL or DL subframe on which a corresponding trigger condition is satisfied, and to transmit the second information block including the second PHR on a first UL subframe immediately following a second trigger UL or DL subframe on which a corresponding trigger condition is satisfied, respectively.

In an exemplary embodiment, the transmitting unit is further configured to transmit the information block via a PHR control unit.

In one exemplary embodiment, the PHR control unit includes: a first data portion comprising the first PHR; a first reserved field associated with the first data portion for carrying a display UL subframe set indication for the first UL subframe set; a second reserved field associated with the first data portion for carrying a power headroom calculation indication for the first set of UL subframes, the power headroom calculation indication for the first set of UL subframes specifying whether the first PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power or a hypothetical reference format corresponding to the first set of UL subframes; a second data portion comprising the second PHR; a third reserved field associated with the second data portion for carrying a display UL subframe set indication for the second UL subframe set; a fourth reserved field associated with the second data portion for carrying a power headroom calculation indication for the second set of UL subframes, the power headroom calculation indication for the second set of UL subframes specifying whether the second PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power or based on a hypothetical reference format corresponding to the second set of UL subframes.

In an exemplary embodiment, the first data portion, the first reserved field and the second reserved field, and the second data portion, the third reserved field and the fourth reserved field are arranged in the PHR control unit in a predetermined order.

In one exemplary embodiment, the transmitting unit is further configured to transmit each of the first information block and the second information block via a PHR control unit.

In an example embodiment, the PHR control element comprises a payload portion including the first or second PHR and a first reserved field carrying the display UL subframe set indication and/or a second reserved field carrying a power headroom calculation indication indicating whether the first or second PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power or based on a hypothetical reference format corresponding to the respective one of the first and second UL subframe sets.

In one exemplary embodiment, the TDD system is configured to support up to five component carriers; wherein the determining unit is further configured to determine, for each of the at most five component carriers, a respective PHR for at least one of the first and second sets of UL subframes in response to a predetermined trigger condition being met for both the first and second sets of UL subframes; and the transmitting unit is further configured to transmit an information block including the PHR on a corresponding one of the at most five component carriers.

In one exemplary embodiment, the transmitting unit is further configured to transmit the information block via a PHR control unit supporting the at most five component carriers.

According to a fourth aspect of embodiments of the present invention, there is provided an apparatus for acquiring a Power Headroom Report (PHR) in a Time Division Duplex (TDD) system configured with a first set of Uplink (UL) subframes and a second set of UL subframes. The apparatus may comprise: a receiving unit configured to receive an information block from a user equipment, the information block comprising a PHR determined for at least one of the first and second UL subframe sets in response to a predetermined trigger condition being met for both the first and second UL subframe sets, and an implicit UL subframe set indication and/or an explicit UL subframe set indication indicating that the determined PHR is for the first or second UL subframe set; and a parsing unit configured to parse the information block to obtain a PHR of the user equipment for at least one of the first UL subframe set and the second UL subframe set.

In one exemplary embodiment, a first PHR for the first UL subframe set and a second PHR for the second UL subframe set are respectively determined in response to satisfying one trigger condition predetermined for both the first UL subframe set and the second UL subframe set; and the receiving unit is further configured to receive an information block including both the first PHR and the second PHR.

In one exemplary embodiment, a first PHR for the first UL subframe set and a second PHR for the second UL subframe set are respectively determined in response to satisfying one trigger condition predetermined for both the first UL subframe set and the second UL subframe set; and the receiving unit is further configured to receive a first information block including the first PHR and a second information block including the second PHR, respectively.

In one exemplary embodiment, a first PHR for the first UL subframe set is determined in response to satisfying a first trigger condition predetermined for the first UL subframe set, and a second PHR for the second UL subframe set is determined in response to satisfying a second trigger condition predetermined for the second UL subframe set; and the receiving unit is further configured to receive a first information block including the first PHR and a second information block including the second PHR, respectively.

In one exemplary embodiment, a first PHR for the first UL subframe set is determined in response to satisfying a first trigger condition predetermined for the first UL subframe set, and a second PHR for the second UL subframe set is determined in response to satisfying a second trigger condition predetermined for the second UL subframe set; and the receiving unit is further configured to receive an information block including both the first PHR and the second PHR.

In one exemplary embodiment, the one of the first and second PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power; and the receiving unit is further configured to receive an information block including the one of the first PHR and the second PHR on one scheduled UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied, the scheduled UL subframe belonging to one of the first UL subframe set and the second UL subframe set.

In one exemplary embodiment, the one of the first and second PHR is determined based on a hypothetical reference format corresponding to the respective one of the first and second UL subframe sets; and wherein the receiving unit is further configured to receive an information block including the one of the first and second PHRs on a first UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied, the first UL subframe belonging to a UL subframe set of the first and second UL subframe sets for which a PHR is determined.

In one exemplary embodiment, both the first PHR and the second PHR are determined based on a maximum transmission power and a pre-allocated UL transmission power; and the receiving unit is further configured to receive an information block including both the first PHR and the second PHR on a later scheduled UL subframe among a first scheduled UL subframe belonging to the first UL subframe set and a second scheduled UL subframe belonging to the second UL subframe set, the later scheduled UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied.

In one exemplary embodiment, one of the first and second PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power, and the other of the first and second PHR is determined based on a hypothetical reference format corresponding to the respective one of the first and second UL subframe sets; and the receiving unit is further configured to receive an information block including both the first PHR and the second PHR on one scheduled UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied, the scheduled UL subframe belonging to one of the first UL subframe set and the second UL subframe set.

In one exemplary embodiment, both the first PHR and the second PHR are determined based on a hypothetical reference format corresponding to a respective one of the first UL subframe set and the second UL subframe set, respectively; and is

In one exemplary embodiment, the receiving unit is further configured to receive an information block including both the first PHR and the second PHR on a first UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied, the first UL subframe belonging to one of the first UL subframe set and the second UL subframe set.

In one exemplary embodiment, both the first PHR and the second PHR are determined based on a maximum transmission power and a pre-allocated UL transmission power; and the receiving unit is further configured to receive a first information block comprising the first PHR on a first scheduled UL subframe and a second information block comprising the second PHR on a second scheduled UL subframe, respectively, the first scheduled UL subframe immediately following a first triggered UL or DL subframe on which the respective trigger condition is satisfied and the second scheduled UL subframe immediately following a second triggered UL or DL subframe on which the respective trigger condition is satisfied.

In one exemplary embodiment, the first PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power, and the second PHR is determined based on a hypothetical reference format corresponding to the second UL subframe set; the receiving unit is further configured to receive the first information block including the first PHR on a scheduled UL subframe immediately following one UL or DL subframe on which the trigger condition is satisfied, the scheduled UL subframe belonging to the first UL subframe set; and the receiving unit is further configured to receive the second information block including the second PHR on a first UL subframe immediately following the one UL or DL subframe on which the trigger condition is satisfied, the first UL subframe belonging to the second UL subframe set.

In one exemplary embodiment, both the first PHR and the second PHR are determined based on a hypothetical reference format corresponding to a respective one of the first UL subframe set and the second UL subframe set, respectively; and the receiving unit is further configured to receive the first information block including the first PHR on a first UL subframe immediately following a first trigger UL or DL subframe on which a corresponding trigger condition is satisfied, and to receive the second information block including the second PHR on a first UL subframe immediately following a second trigger UL or DL subframe on which a corresponding trigger condition is satisfied, respectively.

In an exemplary embodiment, the receiving unit is further configured to receive the information block via a PHR control unit.

In an exemplary embodiment, the receiving unit is further configured to receive each of the first information block and the second information block via a PHR control unit.

In one exemplary embodiment, the TDD system is configured to support up to five component carriers; wherein a respective PHR for each of the at most five component carriers for at least one of the first and second sets of UL subframes is determined in response to a predetermined trigger condition being met for both the first and second sets of UL subframes; and the receiving unit is further configured to receive an information block including the PHR on a corresponding one of the at most five component carriers.

In one exemplary embodiment, the receiving unit is further configured to receive the information block via a PHR control unit supporting the at most five component carriers.

By utilizing the scheme provided by the invention, the UE can provide PHR for one of the first UL subframe set and the second UL subframe set or PHR for both the first UL subframe set and the second UL subframe set for the base station, thereby realizing accurate scheduling of the base station on the UE on different UL subframe sets.

Drawings

The features, advantages and other aspects of embodiments of the present invention will become more apparent by referring to the following detailed description in conjunction with the accompanying drawings, in which several embodiments of the invention are shown by way of illustration and not limitation. In the drawings:

fig. 1 shows a flow diagram of a method 100 for transmitting a power headroom report in a TDD system according to an embodiment of the present invention;

fig. 2 schematically illustrates a MAC control element having a first format when a single CC is employed in a TDD system according to an embodiment of the present invention;

fig. 3 schematically illustrates a MAC control element supporting multi-CC according to an embodiment of the present invention;

fig. 4 schematically shows a multi-CC capable MAC control element according to another embodiment of the present invention

Fig. 5A schematically illustrates a MAC control element having a second format when a single CC is employed in a TDD system according to an embodiment of the present invention;

fig. 5B schematically illustrates a MAC control element having a third format when a single CC is employed in a TDD system according to an embodiment of the present invention;

fig. 6 shows a flow diagram of a method 600 for obtaining a power headroom report in a TDD system according to an embodiment of the present invention;

fig. 7 illustrates a block diagram of an apparatus 700 for transmitting a power headroom report in a TDD system according to an embodiment of the present invention; and

fig. 8 shows a block diagram of an apparatus 700 for acquiring a power headroom report in a TDD system according to an embodiment of the present invention.

Detailed Description

Preferred embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While the preferred embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

The embodiments of the present invention can be applied to various TDD systems, including but not limited to LTE TDD systems, LTE-ATDD systems, LTE TDD eIMTA (Enhanced Interference Management and Traffic Adaptation) systems, LTE-a TDD Enhanced Interference Management and Traffic Adaptation (eIMTA) systems, LTE-a TDD eIMTA systems, and the like. Given the rapid development of communication technologies, there are of course also future types of wireless communication technologies and systems on which embodiments of the present invention may be implemented. Accordingly, the scope of the present invention should not be considered limited to only the above-described systems.

In an undisclosed context, a User Equipment (UE) may refer to a terminal, a Mobile Terminal (MT), a Subscriber Station (SS), a Portable Subscriber Station (PSS), a Mobile Station (MS), or an Access Terminal (AT), and some or all of the functions of the UE, the terminal, the MT, the SS, the PSS, the MS, or the AT may be included.

Furthermore, in an un-disclosed context, a Base Station (BS) may for example denote a node B (NodeB or NB), an evolved NodeB (eNodeB or eNB), a relay station, a low power node, e.g. a femto base station, a pico base station, etc.

Referring initially to fig. 1, a flow diagram of a method 100 for transmitting a Power Headroom Report (PHR) in a Time Division Duplex (TDD) system according to an embodiment of the present invention is shown. The method 100 may be implemented, for example, in a UE, MT, SS, PSS, AT or any other suitable device in a TDD system, according to embodiments of the present invention. In an embodiment according to the present invention, the TDD system is configured with a first set of Uplink (UL) subframes and a second set of UL subframes. As previously described, all or a portion of the UL subframes of a TDD radio frame may be divided into at most two sets of UL subframes such that subframes in one set of UL subframes are interfered by neighboring cells to a lesser degree than subframes in another set of UL subframes are interfered by neighboring cells. Taking configuration 0 in table 1 as an example, the first UL subframe set may include subframe 2 in configuration 0, and the second UL subframe set may include subframes 3, 4, 7, 8, and 9 in configuration 0. As will be appreciated by those skilled in the art, other divisions of the UL subframe set may be used in embodiments of the present invention.

In step S101, in response to a predetermined trigger condition being met for both the first and second sets of UL subframes, a PHR for at least one of the first and second sets of UL subframes is determined.

In case of using a single Component Carrier (CC) in a TDD system, the predetermined trigger condition may include, but is not limited to:

a) a significant change in the path loss estimated since the previous transmission of the PHR (hereinafter, this trigger condition is also referred to as a "path loss change trigger condition");

b) a predetermined time has elapsed since the previous PHR was transmitted, and the trigger condition is controlled by a PHR prohibit timer (PHR prohibit timer) (hereinafter, the trigger condition is also referred to as "timer trigger condition"); and

c) the TPC command implemented by the UE exceeds a predetermined number (hereinafter, this trigger condition is also referred to as "TPC trigger condition").

As understood by those skilled in the art, in case of employing a plurality of component carriers in the TDD system, the trigger condition specified in the current communication specification may be employed.

In one embodiment, the PHR may be determined according to the following formula:

(formula 1)

Wherein:

-PH_type1,cis a power headroom for type 1;

-PH_type2,cis a power headroom for type 2;

-P_CMAX,cmaximum transmit power for the UE;

-M_PUSCH,c(i) is the number of resource units allocated to the ith component carrier;

-P_{O_PUSCH,c}(i) and α_c(j) Is an open loop power control parameter;

-PL_cis the estimated path loss;

-Δ_TF,c(i) is an offset relative to the transport format;

-f_c(i) as a function of closed loop power control commands;

h (-) is a PUCCH format related parameter;

-Δ_{F_PUCCH}(F) is a parameter corresponding to PUCCH format 1 a;

-g (i) is a function of the closed loop power control commands on the ith component carrier.

In step S102, an information block is sent to the base station, the information block including the determined PHR and an implicit UL subframe set indication and/or an explicit UL subframe set indication for indicating that the determined PHR is for the first UL subframe set or the second UL subframe set.

Hereinafter, a method of transmitting a PHR according to an embodiment of the present invention will be described in detail with reference to embodiments 1 to 3.

Embodiment mode 1

In embodiment 1, one trigger condition is predetermined for both the first UL subframe set and the second UL subframe set, one of a first PHR for the first UL subframe set and a second PHR for the second UL subframe set is determined in response to satisfaction of the one trigger condition, and an information block including the one PHR is transmitted to a base station.

Generally, the determination and transmission of PHR is triggered on a certain UL or DL subframe, and thus the UL or DL subframe is also referred to as a "triggered UL or DL subframe". In embodiment 1, when a predetermined trigger condition is met, the determination of PHR for one of the first and second UL subframe sets having the following UL subframes will be triggered: the base station schedules a UL data transmission on the UL subframe and the UL subframe immediately follows a triggering UL or DL subframe on which a triggering condition is satisfied. Accordingly, such UL subframe is hereinafter referred to as "scheduled UL subframe". After determining a PHR for one of the first and second sets of UL subframes, transmitting the PHR with uplink data to the base station on the scheduled UL subframe.

When trigger conditions such as the path loss change trigger condition and the timer trigger condition described above are employed, the same trigger condition is predetermined for both the first and second UL subframe sets. For example, the trigger condition for a change in path loss may be predetermined for both the first and second sets of UL subframes. Specifically, the threshold value of the path loss variation may be predetermined to be 3 dB. When a predetermined threshold is reached, it is determined for the UL subframe set PHR if any one of the first and second UL subframe sets has the above-described scheduled UL subframe. Thus, with a PUSCHU transmission, the information block including the PHR is transmitted to the base station on the scheduled UL subframe. With embodiment 1, the existing PHR trigger scheme can be used to the maximum extent.

When the TPC trigger condition described above, for example, is employed, the number of TPC commands may be calculated separately for the first UL subframe set and the second UL subframe set. The threshold for the number of TPC commands may be predetermined to be 10, for example. When the threshold 10 is reached, the number of TPC commands calculated for the first UL subframe set may be 9, while the number of TPC commands calculated for the first UL subframe set may be 10. Thus, in response to the TPC trigger condition being satisfied, a second PHR for a second set of UL subframes is determined.

In case of employing the TPC trigger condition as described above, when the TPC trigger condition is satisfied, if a triggered UL subframe set (e.g., the second UL subframe set in the above example) has a scheduled UL subframe, a PHR for the triggered UL subframe set may be determined based on a maximum transmission power of the UE and a UL transmission power pre-allocated by the base station (i.e., based on a real UL transmission), for example, may be determined according to the above formula 1. On the other hand, when the TPC trigger condition is satisfied, if a triggered UL subframe set (e.g., the second UL subframe set in the above example) does not have a scheduled UL subframe, and an un-triggered UL subframe set (e.g., the first UL subframe set in the above example) has a scheduled UL subframe, a PHR for the triggered UL subframe set is determined as an estimated value of the PHR based on a hypothetical reference format (lower reliability format) corresponding to the triggered UL subframe set. In this case, the estimated value of PHR may still be determined, for example, using equation 1. It can be appreciated that when the base station schedules UL transmission, the base station will issue the values of the relevant parameters (e.g., MCS, TPC closed loop power control adjustment) in equation 1 to the UE in UL grant signaling. Since there is no scheduled UL subframe belonging to the triggered UL subframe set at this time, the UE cannot obtain the value of the relevant parameter in equation 1 through UL grant signaling. In this case, a reference value of the relevant parameter in equation 1 may be determined in advance, and an estimated value of PHR may be calculated using the reference value based on equation 1. Thereafter, an information block including the determined PHR is transmitted on a first UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied, the first UL subframe belonging to a UL subframe set for which the PHR is determined among a first UL subframe set and a second UL subframe set.

Upon receiving the PHR, the base station should be able to identify which UL subframe set of the first and second UL subframe sets the PHR is for. Specifically, the base station may identify which UL subframe set the PHR is for by an implicit subframe set indication contained in the information block. As described above, each subframe in a TDD radio frame has a corresponding index, i.e., 0, 1, 2. The implicit subframe set indication may be an index of a UL subframe set on which an information block (including the determined PHR) is transmitted. For example, the first UL subframe set includes subframes with index 2, the second UL subframe set includes subframes with index 3, 7, 8, and both the base station and the UE know in advance which UL subframes specifically included in the two UL subframe sets. If the UE transmits an information block including a PHR on the UL subframe index of 2, the base station will receive the information block on the UL subframe index of 2, so that it can be recognized that the PHR included in the information block is for the first UL subframe set.

However, since the UL retransmission Round Trip Time (RTT) is not 10ms for configurations 0 and 6 in a TDD system, for an initial PHR for one UL subframe set, its retransmission may occur on another UL subframe set. Therefore, it is only distinguished by the index of the UL subframe for which UL subframe set the PHR is unreliable. In this case, the base station may identify which UL subframe set the PHR is for by an explicit subframe set indication contained in the information block. Specifically, the present application proposes to transmit an information block including a PHR via a Medium Access Control (MAC) Control Element (CE) of an embodiment of the present invention.

Fig. 2 schematically shows a MAC control element having a first format when a single CC is employed in a TDD system. As shown in fig. 2, the MAC control element for a single CC includes 6 bits for carrying a power headroom value and two reserved bits, respectively denoted R in fig. 2₁And R₂And (4) showing. Thus, two reserved bits R₁And R₂May be used to carry an explicit subframe set indication indicating that the determined PHR is for the first UL subframe set or the second UL subframe set. For example, when R is used₂To carry an explicit subframe set indication, it may be preset when R is₂Indicates that PHR is for the first UL subframe set when the value of (A) is 0, and when R is₂A value of 1 indicates that PHR is for the second UL subframe set.

To distinguish whether PHRs contained in an information block are determined based on a maximum transmission power and a pre-allocated UL transmission power (i.e., based on a true UL transmission) or based on a hypothetical reference format corresponding to a respective UL subframe setAlternatively, another reserved field R may be used₁To carry a power headroom calculation manner indication indicating whether the PHR contained in the information block is determined based on the maximum transmission power and the pre-allocated UL transmission power or based on the assumed reference format corresponding to the respective UL subframe set. For example, R can be preset₁Indicates that PHR is determined based on the maximum transmission power and the pre-allocated UL transmission power when the value of (A) is 0, and indicates that PHR is determined when R is less than or equal to 0₁Indicates that the PHR is an estimated value determined based on a hypothetical reference format corresponding to the respective UL subframe set when the value of (1) is set.

It should be noted that the base station does not utilize the reserved bits (e.g., R) in the MAC control element described above since the base station knows whether the UL subframe on which the PHR is transmitted is scheduled or not₁) It can also be recognized whether the received PHR is determined based on a real UL transmission.

When a Carrier Aggregation (CA) user of a TDD system, in particular a TDD eIMTA system, is configured to support multiple (up to five) component carriers, for each of the up to five component carriers, in response to a predetermined trigger condition being met for both a first UL subframe set and a second UL subframe set, determining a respective PHR for at least one of the first UL subframe set and the second UL subframe set, and transmitting an information block including the PHR on the respective one of the up to five component carriers. Specifically, there are the following two cases.

Case 1

eIMTA occurs only for primary cells (Pcell), while eIMTA does not exist for secondary cells (Scell). The UE only needs to indicate which UL subframe set is used for the calculation of the two PHR values for the Pcell. In this case, the PHR may be transmitted to the base station via a PHR control unit supporting a plurality of component carriers, for example, via a MAC control unit supporting a plurality of component carriers.

Fig. 3 schematically shows a MAC control unit supporting multiple component carriers according to one embodiment of the present invention. In the MAC control element shown in fig. 3, each of C1, C2, C3... C7 indicates an index of a corresponding carrier component; pcmax, ci (i =1.. m) indicates the maximum transmit power on the ith component carrier; "P" indicates whether a value of Pcmax, ci is present; PH (Type1, Pcell) indicates a Type1 power headroom for Pcell; associated with PH (Type1, Pcell) (i.e., "V" in the same byte as PH (Type1, Pcell)), a value of 0 indicates that PH (Type1, Pcell) is determined based on real transmission on PUSCH, and a value of 1 indicates that PH (Type1, Pcell) is determined based on PUSCH reference format; PH (Type2, Pcell) indicates a Type2 power headroom for Pcell; associated with PH (Type2, Pcell) (i.e., "V" in the same byte as PH (Type2, Pcell)), a value of 0 indicates that PH (Type2, Pcell) is determined based on real transmission on PUCCH, and a value of 1 indicates that PH (Type2, Pcell) is determined based on PUCCH reference format; PH (Type1, sceli (i =1.. n)) indicates a power headroom of Type1 for Scell; r is a reserved field. The reserved field R may be used to carry an explicit UL subframe set indication. For example, it may be preset to indicate that PHR is for the first UL subframe set when the value of R is 0, and indicate that PHR is for the second UL subframe set when the value of R is 1.

It should be noted that when the PHR is determined based on the assumed reference format of the corresponding UL subframe set (e.g., based on the PUSCH reference format or the PUCCH reference format), the bit "V" is already included in the MAC control element in fig. 3 to indicate whether the corresponding power headroom value is determined based on the real UL transmission or the assumed reference format, and thus, there is no need to indicate with an additional bit.

Case 2

In case both Pcell and Scell support eIMTA, the UE should indicate whether the determined PHR is for the first or second set of UL subframes for both Pcell and Scell. When eIMTA is implemented for all component carriers, different component carriers may have different TDD UL-DL configurations. The first and second sets of UL subframes on different component carriers may be different from each other based on a degree of UL interference by a neighboring cell. Accordingly, an explicit UL subframe set indication may be added in the MAC control element of fig. 3 to indicate for which UL subframe set the transmitted PHR is for, for a plurality of component carriers, as shown in fig. 4. In fig. 4, 1 byte is added in the MAC control element to carry the explicit UL subframe set indication. The explicit UL subframe set indication is associated with a component carrier indication, i.e. the explicit UL subframe set indication I-C1, I-C2... I-C7 for the respective component carrier corresponds to the component carrier indication C1, C2... C7, respectively. For example, C1 indicates the 1 st component carrier among the above-described up to five component carriers, I-C1=0 indicates that the determined PHR (e.g., PH (Type1, Pcell)) is for the first UL subframe set for the 1 st component carrier, and I-C1=1 indicates that the determined PHR (e.g., PH (Type1, Pcell)) is for the second UL subframe set for the 1 st component carrier.

Embodiment mode 2

In embodiment 2, a first PHR for the first UL subframe set and a second PHR for the second UL subframe set are determined, respectively, in response to one trigger condition predetermined for both the first UL subframe set and the second UL subframe set being satisfied.

In embodiment 2, the trigger conditions described in embodiment 1, for example, a path loss change trigger condition, a timer trigger condition, a TPC trigger condition, and the like may be employed. As described above, the first and second UL subframe sets share the same timer and path loss variation threshold, while the number of TPC commands can be calculated separately for the first and second UL subframe sets. Once a trigger condition is satisfied, a first PHR for a first UL subframe set and a second PHR for a second UL subframe set are determined, respectively. For the determination and transmission of the first PHR and the second PHR, there are the following two schemes.

Scheme 1: transmitting an information block including both a first PHR and a second PHR

In scheme 1, there are 3 cases as follows.

Case 1: determining both the first PHR and the second PHR based on the maximum transmission power and the pre-allocated UL transmission power, and transmitting an information block including both the first PHR and the second PHR on a later scheduled UL subframe among a first scheduled UL subframe belonging to the first UL subframe set and a second scheduled UL subframe belonging to the second UL subframe set, the later scheduled UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied.

Case 2: determining one of the first and second PHRs based on a maximum transmission power and a pre-allocated UL transmission power, and determining the other of the first and second PHRs based on a hypothetical reference format corresponding to the respective one of the first and second sets of UL subframes, and transmitting an information block including both the first and second PHRs on one scheduled UL subframe immediately following a trigger UL or DL subframe on which a trigger condition is satisfied, the scheduled UL subframe belonging to one of the first and second sets of UL subframes.

Case 3: determining a first PHR based on a hypothetical reference format corresponding to a first UL subframe set, and determining a second PHR based on a hypothetical reference format corresponding to a second UL subframe set; and transmitting an information block including both the first PHR and the second PHR on a first UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied, wherein the first UL subframe belongs to one of the first UL subframe set and the second UL subframe set.

When a single CC is employed in the TDD system, the information block in scheme 1 may be transmitted using a MAC control element having a second format as shown in fig. 5A.

As shown in fig. 5A, the MAC control element having the second format includes a first data portion 501(6 bits), a reserved field V associated with the first data portion 501₁A second data portion 502(6 bits), a reserved field V associated with the second data portion 502₂. The first data portion 501 includes a first PHR, a reserved field V₁For carrying a power headroom calculation mode indication for the first UL subframe set indicating whether the first PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power or a hypothetical reference format corresponding to the first UL subframe set. For example, it can be preset when V₁Indicates that the first PHR is determined based on the maximum transmission power and the pre-allocated UL transmission power when V =0₁Indication when =1 corresponds toThe hypothetical reference format of the first set of UL subframes is determined.

The second data portion 502 includes a second PHR, a reserved field V₂For carrying a power headroom calculation mode indication for the second UL subframe set indicating whether the second PHR is determined based on the maximum transmission power and the pre-allocated UL transmission power or based on a hypothetical reference format corresponding to the second UL subframe set. For example, it can be preset when V₂Indicates that the second PHR is determined based on the maximum transmission power and the pre-allocated UL transmission power when V =0₂Is determined indicating a hypothetical reference format corresponding to the second UL subframe set when =1.

The base station may determine for which UL subframe set the first and second data portions, respectively, are intended by an implicit UL subframe set indication. Furthermore, the first data portion 501 and the reserved field V may also be combined₁And a second data portion 502 and a reserved field V₂Are arranged in the MAC control unit in a predetermined order. For example, the first data portion 501 and the reserved field V associated therewith may be predetermined₁Preceding said second data portion 502 and the reserved field V associated therewith₂. Thus, the base station may know that the first data portion 501 is for the first set of UL subframes. Alternatively, the second data portion 502 and the reserved field V associated therewith may also be predetermined₂Prior to the first data portion 501 and the reserved field V associated therewith₁。

When a single CC is employed in the TDD system, the information block in scheme 1 may also be transmitted using a MAC control element having a third format as shown in fig. 5B. The difference between the MAC control element shown in fig. 5B and the MAC control element shown in fig. 5A is that the reserved field I is utilized₁And I₂To carry an explicit UL subframe set indication for the first UL subframe set and an explicit UL subframe set indication for the second UL subframe set, respectively.

It should be noted that it is also possible to use only the reserved field I₁And I₂To carry an explicit UL subframe setAnd (4) indicating. For example, with I₁In time, I can be preset₁=0 indicates that the first data portion 501 is PHR, I for the first UL subframe set₁=1 indicates that the first data portion 501 is a PHR for the second UL subframe set.

It can be appreciated that layer 2 signaling can be saved by using the MAC control element shown in fig. 5A and 5B to transmit an information block including a first PHR and a second PHR.

When a plurality of component carriers are employed in the TDD system, an information block including the first PHR and the second PHR may be transmitted via the MAC control element shown in fig. 3, but a definition of the reserved field "R" therein needs to be modified. Specifically, a first PHR and a second PHR are inserted into the MAC control element shown in fig. 3 in a predetermined order, and the order of the first PHR and the second PHR is indicated by different values of "R". For example, R =0 indicates that the first PHR precedes the second PHR, and R =1 indicates that the second PHR precedes the first PHR.

It should be noted that in this embodiment, when a single trigger condition is maintained for the first and second UL subframe sets, two timers may be used, for example, periodicPHR-Timer (periodic PHR Timer) and prohibitPHR-Timer (PHR prohibit Timer), and the two timers respectively count time, and when one of the timers expires, the two PHR are triggered to report respectively. As an alternative, only one timer may be used to reduce the reporting burden.

Scheme 2: transmitting a first information block including a first PHR and a second information block including a second PHR, respectively

In scheme 2, there are 3 cases as follows.

Case 1: determining both the first PHR and the second PHR based on the maximum transmission power and a pre-allocated UL transmission power; and transmitting a first information block including a first PHR on a first scheduled UL subframe and a second information block including a second PHR on a second scheduled UL subframe, respectively, the first scheduled UL subframe immediately following a first trigger UL or DL subframe on which a corresponding trigger condition is satisfied, and the second scheduled UL subframe immediately following a second trigger UL or DL subframe on which the corresponding trigger condition is satisfied.

Case 2: determining a first PHR based on a maximum transmission power and a pre-allocated UL transmission power, and determining a second PHR based on a hypothetical reference format corresponding to a second UL subframe set; transmitting a first information block including a first PHR on a scheduled UL subframe immediately following one UL or DL subframe on which a trigger condition is satisfied, the scheduled UL subframe belonging to a first UL subframe set; and transmitting a second information block including a second PHR on a first UL subframe immediately following one UL or DL subframe on which the trigger condition is satisfied, the first UL subframe belonging to a second UL subframe set.

Case 2: determining both a first PHR and a second PHR based on a hypothetical reference format corresponding to a respective one of a first UL subframe set and a second UL subframe set, respectively; and transmitting a first information block including a first PHR on a first UL subframe immediately following a first trigger UL or DL subframe on which the corresponding trigger condition is satisfied, and transmitting a second information block including a second PHR on a first UL subframe immediately following a second trigger UL or DL subframe on which the corresponding trigger condition is satisfied, respectively.

When a single CC is employed in the TDD system, the information block in scheme 2 may be transmitted, for example, using a MAC control element having a second format as shown in fig. 2. When multiple CCs are employed in the TDD system, the information block in scheme 2 may be transmitted, for example, using a MAC control element as shown in fig. 3 or 4.

Embodiment 3

In embodiment 3, a first PHR for a first UL subframe set is determined in response to satisfaction of a first trigger condition predetermined for the first UL subframe set, and a second PHR for a second UL subframe set is determined in response to satisfaction of a second trigger condition predetermined for the second UL subframe set. In this case, a respective timer or the like needs to be maintained for each UL subframe set.

As for the determination of the first PHR and the second PHR, the manner described in embodiment mode 1 may be referred to. For example, the first PHR and the second PHR are both determined based on a true UL transmission, or both are determined based on a corresponding hypothetical reference format, or one of the PHR is determined based on a true UL transmission and the other PHR is determined based on a corresponding hypothetical reference format.

As for the manner of the first and second PHR, a first information block including the first PHR and a second information block including the second PHR may be transmitted, respectively. The information block including the PHR is transmitted, for example, via the MAC control element in fig. 2, 3, or 4. Alternatively, an information block including both the first PHR and the second PHR may be transmitted. For example, an information block including the first and second PHR is transmitted via the MAC control element in fig. 5A or 5B.

According to a second aspect of embodiments of the present invention, there is provided a method for acquiring a Power Headroom Report (PHR) in a Time Division Duplex (TDD) system configured with a first set of Uplink (UL) subframes and a second set of UL subframes. Fig. 6 shows a flow diagram of a method 600 for acquiring a Power Headroom Report (PHR) in a Time Division Duplex (TDD) system according to an embodiment of the present invention. The method 600 comprises: in step S601, receiving an information block from a user equipment, the information block comprising a PHR determined for at least one of a first UL subframe set and a second UL subframe set in response to a predetermined trigger condition being met for both the first UL subframe set and the second UL subframe set, and an implicit UL subframe set indication and/or an explicit UL subframe set indication for indicating that the determined PHR is for the first UL subframe set or the second UL subframe set; and in step S602, parsing the information block to obtain a PHR of the user equipment for at least one UL subframe set of the first UL subframe set and the second UL subframe set.

The method 600 may be implemented in a base station, a NodeB, an eNodeB, a relay, a low power node (e.g., a femto base station, a pico base station, etc.), or any other suitable device in a TDD system.

According to a third aspect of embodiments of the present invention, there is provided an apparatus for transmitting a Power Headroom Report (PHR) in a Time Division Duplex (TDD) system configured with a first set of Uplink (UL) subframes and a second set of UL subframes. Fig. 7 illustrates a block diagram of an apparatus 700 for transmitting a PHR in a TDD system according to an embodiment of the present invention. The apparatus 700 comprises: a determining unit 701 configured to determine a PHR for at least one of the first and second UL subframe sets in response to a predetermined trigger condition being satisfied for both the first and second UL subframe sets; and a transmitting unit 702 configured to transmit an information block to the base station, the information block comprising the determined PHR and an implicit UL subframe set indication and/or an explicit UL subframe set indication for indicating that the determined PHR is for the first UL subframe set or the second UL subframe set. The apparatus 700 may be implemented, for example, in a UE, MT, SS, PSS, AT, or any other suitable device in a TDD system.

According to a fourth aspect of embodiments of the present invention, there is provided an apparatus for acquiring a Power Headroom Report (PHR) in a Time Division Duplex (TDD) system configured with a first set of Uplink (UL) subframes and a second set of UL subframes. Fig. 8 illustrates a block diagram of an apparatus 800 for acquiring a PHR in a TDD system according to an embodiment of the present invention. The apparatus 800 comprises: a receiving unit 801 configured to receive an information block from a user equipment, the information block including a PHR determined for at least one of a first UL subframe set and a second UL subframe set in response to a predetermined trigger condition being met for both the first UL subframe set and the second UL subframe set, and an implicit UL subframe set indication and/or an explicit UL subframe set indication for indicating the determined PHR for the first UL subframe set or the second UL subframe set; and a parsing unit 802 configured to parse the information block to obtain a PHR of the user equipment for at least one UL subframe set of the first UL subframe set and the second UL subframe set. The apparatus 700 may be implemented, for example, in a base station, a NodeB, an eNodeB, a relay station, a low power node (e.g., a femto base station, a pico base station, etc.), or any other suitable device in a TDD system.

The reader of this application will also understand that the word "comprising" or "comprises" does not exclude other elements or steps, and the word "a" or "an" does not exclude a plurality, and that a single element, such as a computer system, processor or other integrated unit may fulfil the functions of several means recited in the claims. Any reference sign in a claim should not be construed as limiting the associated corresponding claim. The terms "first," "second," "third," and the like, when used in the description or in the claims, are introduced to distinguish between similar elements or steps and do not necessarily describe a sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention are capable of operation in other sequences and orientations than described or illustrated above in accordance with the invention.

Although the present invention has been described with reference to specific embodiments, it will be apparent to those skilled in the art that the present invention is not limited to the details of the foregoing described embodiments, and that the present invention may be embodied with various changes and modifications without departing from the scope of the invention. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

It should be understood that aspects of the present invention may be implemented in any form, including hardware, software, firmware, or any combination thereof. The elements and components of an embodiment of the invention may be physically, functionally and logically implemented in any suitable way. Of course, the functionality may be implemented in a single unit or IC, in a plurality of units or ICs or as part of other functional units.

Claims

1. A method for transmitting a Power Headroom Report (PHR) in a Time Division Duplex (TDD) system configured with a first set of Uplink (UL) subframes and a second set of UL subframes, the method comprising:

determining a PHR for at least one of the first and second sets of UL subframes in response to a predetermined trigger condition being met for both the first and second sets of UL subframes; and

transmitting an information block to a base station, the information block including the determined PHR and an explicit UL subframe set indication indicating that the determined PHR is for the first UL subframe set or the second UL subframe set,

wherein sending the information block to the base station comprises:

transmitting the information block via a PHR control element, the PHR control element comprising a reserved field for determining to carry the explicit UL subframe set indication and another reserved field for carrying a power headroom calculation manner indication.

2. The method of claim 1, wherein one of a first PHR for the first UL subframe set and a second PHR for the second UL subframe set is determined in response to one trigger condition predetermined for both the first UL subframe set and the second UL subframe set being met.

3. The method of claim 1, wherein a first PHR for the first UL subframe set and a second PHR for the second UL subframe set are determined, respectively, in response to one trigger condition predetermined for both the first UL subframe set and the second UL subframe set being met; and is

Wherein an information block including both the first PHR and the second PHR is transmitted.

4. The method of claim 1, wherein a first PHR for the first UL subframe set and a second PHR for the second UL subframe set are determined, respectively, in response to one trigger condition predetermined for both the first UL subframe set and the second UL subframe set being met; and is

Wherein a first information block including the first PHR and a second information block including the second PHR are transmitted, respectively.

5. The method of claim 1, wherein a first PHR for the first UL subframe set is determined in response to a first trigger condition predetermined for the first UL subframe set being met, and a second PHR for the second UL subframe set is determined in response to a second trigger condition predetermined for the second UL subframe set being met; and is

6. The method of claim 1, wherein a first PHR for the first UL subframe set is determined in response to a first trigger condition predetermined for the first UL subframe set being met, and a second PHR for the second UL subframe set is determined in response to a second trigger condition predetermined for the second UL subframe set being met; and is

7. The method of claim 2, wherein the one of the first and second PHRs is determined based on a maximum transmission power and a pre-allocated UL transmission power; and is

Wherein an information block including the one of the first PHR and the second PHR is transmitted on one scheduled UL subframe immediately following a triggering UL or DL subframe on which the triggering condition is satisfied, the scheduled UL subframe belonging to one of the first UL subframe set and the second UL subframe set.

8. The method of claim 2, wherein the one of the first PHR and the second PHR is determined based on a hypothetical reference format corresponding to a respective one of the first UL subframe set and the second UL subframe set; and is

Wherein an information block including the one of the first PHR and the second PHR is transmitted on a first UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied, the first UL subframe belonging to a UL subframe set for which a PHR is determined among the first UL subframe set and the second UL subframe set.

9. The method of claim 3, wherein both the first PHR and the second PHR are determined based on a maximum transmission power and a pre-allocated UL transmission power; and wherein an information block including both the first PHR and the second PHR is transmitted on a later scheduled UL subframe among a first scheduled UL subframe belonging to the first UL subframe set and a second scheduled UL subframe belonging to the second UL subframe set, the later scheduled UL subframe immediately following a triggering UL or DL subframe on which the triggering condition is satisfied.

10. The method of claim 3, wherein one of the first PHR and the second PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power, and the other of the first PHR and the second PHR is determined based on a hypothetical reference format corresponding to the respective one of the first UL subframe set and the second UL subframe set; and is

Wherein an information block including both the first PHR and the second PHR is transmitted on one scheduled UL subframe immediately following a triggering UL or DL subframe on which the triggering condition is satisfied, the scheduled UL subframe belonging to one of the first UL subframe set and the second UL subframe set.

11. The method of claim 3, wherein both the first PHR and the second PHR are determined based on a hypothetical reference format corresponding to a respective one of the first UL subframe set and the second UL subframe set, respectively; and is

Wherein an information block including both the first PHR and the second PHR is transmitted on a first UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied, the first UL subframe belonging to one of the first UL subframe set and the second UL subframe set.

12. The method of claim 4, wherein both the first PHR and the second PHR are determined based on a maximum transmission power and a pre-allocated UL transmission power; and is

Wherein a first information block comprising the first PHR is transmitted on a first scheduled UL subframe and a second information block comprising the second PHR is transmitted on a second scheduled UL subframe, respectively, the first scheduled UL subframe immediately following a first triggered UL or DL subframe on which a respective trigger condition is satisfied, and the second scheduled UL subframe immediately following a second triggered UL or DL subframe on which a respective trigger condition is satisfied.

13. The method of claim 4, wherein the first PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power, and the second PHR is determined based on a hypothetical reference format corresponding to the second UL subframe set;

wherein the first information block comprising the first PHR is transmitted on one scheduled UL subframe immediately following one UL or DL subframe on which the trigger condition is satisfied, the scheduled UL subframe belonging to the first UL subframe set; and is

Wherein the second information block including the second PHR is transmitted on a first UL subframe immediately following the one UL or DL subframe on which the trigger condition is satisfied, the first UL subframe belonging to the second UL subframe set.

14. The method of claim 4, wherein both the first PHR and the second PHR are determined based on a hypothetical reference format corresponding to a respective one of the first UL subframe set and the second UL subframe set, respectively; and is

Wherein the first information block including the first PHR is transmitted on a first UL subframe immediately following a first trigger UL or DL subframe on which a respective trigger condition is satisfied, and the second information block including the second PHR is transmitted on a first UL subframe immediately following a second trigger UL or DL subframe on which a respective trigger condition is satisfied, respectively.

15. The method of claim 1, wherein:

the PHR control element includes a payload portion including a first PHR, a second PHR, a first reserved field, and/or a second reserved field, the first reserved field carrying the explicit UL subframe set indication, the second reserved field carrying a power headroom calculation indication indicating whether the first or second PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power or a hypothetical reference format corresponding to respective ones of the first and second UL subframe sets.

16. The method of claim 1, wherein the PHR control unit comprises:

a first data portion comprising a first PHR;

a third reserved field associated with the first data portion for carrying a power headroom calculation indication for the first set of UL subframes, the power headroom calculation indication for the first set of UL subframes specifying whether the first PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power or a hypothetical reference format corresponding to the first set of UL subframes;

a second data portion comprising a second PHR; and

a fourth reserved field associated with the second data portion for carrying a power headroom calculation indication for the second set of UL subframes, the power headroom calculation indication for the second set of UL subframes specifying whether the second PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power or based on a hypothetical reference format corresponding to the second set of UL subframes.

17. The method as in claim 16 wherein the PHR control element further comprises a fifth reserved field associated with the first data portion for carrying an explicit UL subframe set indication for the first UL subframe set and/or a sixth reserved field associated with the second data portion for carrying an explicit UL subframe set indication for the second UL subframe set.

18. The method of claim 16, wherein the first data portion and the third reserved field, and the second data portion and the fourth reserved field, are arranged in the PHR control unit in a predetermined order.

19. The method of claim 18, wherein the predetermined order comprises one of:

20. The method of any of claims 12-14, wherein transmitting the information block via a PHR control element comprises:

transmitting each of the first information block and the second information block via a PHR control unit.

21. The method of claim 20, wherein the PHR control element comprises a payload portion including the first or second PHR, and a seventh reserved field carrying the explicit UL subframe set indication and/or an eighth reserved field carrying a power headroom calculation indication specifying whether the first or second PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power or a hypothetical reference format corresponding to a respective one of the first and second UL subframe sets.

22. The method of claim 1, wherein a carrier aggregation user of the TDD system is configured to support up to five component carriers;

wherein for each of the at most five component carriers, in response to a predetermined trigger condition being met for both the first and second sets of UL subframes, determining a respective PHR for at least one of the first and second sets of UL subframes; and is

Wherein an information block including the PHR is transmitted on a corresponding one of the at most five component carriers.

23. The method of claim 22, wherein the information block is transmitted via a PHR control unit supporting the at most five component carriers.

24. The method of claim 23, wherein the PHR control element supporting the up to five component carriers comprises a component carrier indication and the explicit UL subframe set indication associated with the component carrier indication, the explicit UL subframe set indication indicating whether the determined PHR for the respective component carrier is for the first UL subframe set or the second UL subframe set.

25. A method for acquiring a Power Headroom Report (PHR) in a Time Division Duplex (TDD) system configured with a first set of Uplink (UL) subframes and a second set of UL subframes, the method comprising:

receiving an information block from a user equipment, the information block comprising a PHR determined for at least one of the first and second sets of UL subframes in response to a predetermined trigger condition being met for both the first and second sets of UL subframes, and an explicit UL subframe set indication indicating that the determined PHR is for the first or second set of UL subframes; and

parsing the information block to obtain PHRs of the user equipment for at least one of the first and second sets of UL subframes,

wherein receiving the information block from the user equipment comprises:

receiving the information block via a PHR control element comprising a reserved field for determining to carry the explicit UL subframe set indication and another reserved field for carrying a power headroom calculation indication.

26. The method of claim 25, wherein one of a first PHR for the first UL subframe set and a second PHR for the second UL subframe set is determined in response to satisfying a predetermined one trigger condition for both the first UL subframe set and the second UL subframe set.

27. The method of claim 25, wherein a first PHR for the first UL subframe set and a second PHR for the second UL subframe set are respectively determined in response to satisfying one trigger condition predetermined for both the first UL subframe set and the second UL subframe set; and is

Wherein an information block including both the first PHR and the second PHR is received.

28. The method of claim 25, wherein a first PHR for the first UL subframe set and a second PHR for the second UL subframe set are respectively determined in response to satisfying one trigger condition predetermined for both the first UL subframe set and the second UL subframe set; and is

Wherein a first information block including the first PHR and a second information block including the second PHR are received, respectively.

29. The method of claim 25, wherein a first PHR for the first UL subframe set is determined in response to satisfying a first trigger condition predetermined for the first UL subframe set, and a second PHR for the second UL subframe set is determined in response to satisfying a second trigger condition predetermined for the second UL subframe set; and is

30. The method of claim 25, wherein a first PHR for the first UL subframe set is determined in response to satisfying a first trigger condition predetermined for the first UL subframe set, and a second PHR for the second UL subframe set is determined in response to satisfying a second trigger condition predetermined for the second UL subframe set; and is

31. The method of claim 26, wherein the one of the first PHR and the second PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power; and is

Wherein an information block including the one of the first PHR and the second PHR is received on one scheduled UL subframe immediately following a triggering UL or DL subframe on which the triggering condition is satisfied, the scheduled UL subframe belonging to one of the first UL subframe set and the second UL subframe set.

32. The method of claim 26, wherein the one of the first and second PHR is determined based on a hypothetical reference format corresponding to a respective one of the first and second sets of UL subframes; and is

Wherein an information block including the one of the first PHR and the second PHR is received on a first UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied, the first UL subframe belonging to a UL subframe set for which a PHR is determined among the first UL subframe set and the second UL subframe set.

33. The method of claim 27, wherein both the first PHR and the second PHR are determined based on a maximum transmission power and a pre-allocated UL transmission power; and is

Wherein an information block including both the first PHR and the second PHR is received on a later scheduled UL subframe among a first scheduled UL subframe belonging to the first UL subframe set and a second scheduled UL subframe belonging to the second UL subframe set, the later scheduled UL subframe immediately following a triggering UL or DL subframe on which the triggering condition is satisfied.

34. The method of claim 27, wherein one of the first and second PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power, and the other of the first and second PHR is determined based on a hypothetical reference format corresponding to the respective one of the first and second sets of UL subframes; and is

Wherein an information block including both the first PHR and the second PHR is received on one scheduled UL subframe immediately following a triggering UL or DL subframe on which the triggering condition is satisfied, the scheduled UL subframe belonging to one of the first UL subframe set and the second UL subframe set.

35. The method of claim 27, wherein both the first PHR and the second PHR are determined based on a hypothetical reference format corresponding to a respective one of the first UL subframe set and the second UL subframe set, respectively; and is

Wherein an information block including both the first PHR and the second PHR is received on a first UL subframe immediately following a trigger UL or DL subframe on which the trigger condition is satisfied, the first UL subframe belonging to one of the first UL subframe set and the second UL subframe set.

36. The method of claim 28, wherein both the first PHR and the second PHR are determined based on a maximum transmission power and a pre-allocated UL transmission power; and is

Wherein a first information block comprising the first PHR is received on a first scheduled UL subframe and a second information block comprising the second PHR is received on a second scheduled UL subframe, respectively, the first scheduled UL subframe immediately following a first trigger UL or DL subframe on which a respective trigger condition is satisfied and the second scheduled UL subframe immediately following a second trigger UL or DL subframe on which a respective trigger condition is satisfied.

37. The method of claim 28, wherein the first PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power, and the second PHR is determined based on a hypothetical reference format corresponding to the second UL subframe set;

wherein the first information block comprising the first PHR is received on a scheduled UL subframe immediately following one UL or DL subframe on which the trigger condition is satisfied, the scheduled UL subframe belonging to the first set of UL subframes; and is

Wherein the second information block including the second PHR is received on a first UL subframe immediately following the one UL or DL subframe on which the trigger condition is satisfied, the first UL subframe belonging to the second UL subframe set.

38. The method of claim 28, wherein both the first PHR and the second PHR are determined based on a hypothetical reference format corresponding to a respective one of the first UL subframe set and the second UL subframe set, respectively; and is

Wherein the first information block including the first PHR is received on a first UL subframe immediately following a first trigger UL or DL subframe on which a respective trigger condition is satisfied, and the second information block including the second PHR is received on a first UL subframe immediately following a second trigger UL or DL subframe on which a respective trigger condition is satisfied, respectively.

39. The method of claim 25, wherein:

40. The method of claim 25, wherein the PHR control unit comprises:

a first data portion comprising a first PHR;

a second data portion comprising a second PHR; and

41. The method as in claim 40 wherein the PHR control element further comprises a fifth reserved field associated with the first data portion for carrying an explicit UL subframe set indication for the first UL subframe set and/or a sixth reserved field associated with the second data portion for carrying an explicit UL subframe set indication for the second UL subframe set.

42. The method of claim 40, wherein the first data portion and the third reserved field, and the second data portion and the fourth reserved field, are arranged in the PHR control unit in a predetermined order.

43. The method of claim 42, wherein the predetermined order comprises one of:

44. The method of any of claims 36-38, wherein receiving the information block via a PHR control unit comprises:

receiving each of the first information block and the second information block via a PHR control unit.

45. The method of claim 44, wherein the PHR control element comprises a payload portion comprising the first or second PHR and a seventh reserved field carrying the explicit UL subframe set indication and/or an eighth reserved field carrying a power headroom calculation indication specifying whether the first or second PHR is determined based on a maximum transmission power and a pre-allocated UL transmission power or based on a hypothetical reference format corresponding to respective ones of the first and second UL subframe sets.

46. The method of claim 25, wherein a carrier aggregation base station of the TDD system is configured to support up to five component carriers;

wherein a respective PHR for each of the at most five component carriers for at least one of the first and second sets of UL subframes is determined in response to a predetermined trigger condition being met for both the first and second sets of UL subframes; and is

Wherein an information block including the PHR is received on a respective one of the at most five component carriers.

47. The method of claim 46, wherein the information block is received via a PHR control unit that supports the at most five component carriers.

48. The method of claim 47, wherein the PHR control element supporting the up to five component carriers comprises a component carrier indication and the explicit UL subframe set indication indicating power with the component carrier, the explicit UL subframe set indication indicating whether the determined PHR for the respective component carrier is for the first UL subframe set or the second UL subframe set.

49. An apparatus for transmitting a Power Headroom Report (PHR) in a Time Division Duplex (TDD) system configured with a first set of Uplink (UL) subframes and a second set of UL subframes, the apparatus comprising:

a determining unit configured to determine a PHR for at least one of the first and second sets of UL subframes in response to a predetermined trigger condition being met for both the first and second sets of UL subframes; and

a transmitting unit configured to transmit an information block to a base station, the information block including the determined PHR and an explicit UL subframe set indication indicating that the determined PHR is for the first UL subframe set or the second UL subframe set,

wherein the transmitting unit is further configured to:

50. An apparatus for acquiring a Power Headroom Report (PHR) in a Time Division Duplex (TDD) system configured with a first set of Uplink (UL) subframes and a second set of UL subframes, the apparatus comprising:

a receiving unit configured to receive an information block from a user equipment, the information block comprising a PHR determined for at least one of the first and second sets of UL subframes in response to a predetermined trigger condition being met for both the first and second sets of UL subframes, and an explicit UL subframe set indication indicating that the determined PHR is for the first or second set of UL subframes; and

a parsing unit configured to parse the information block to obtain PHRs of the user equipment for at least one of the first and second sets of UL subframes,

wherein the receiving unit is further configured to: