RU2751152C2 - Dynamic uplink/downlink tdd configuration using dci - Google Patents

Abstract

FIELD: computer technology.

SUBSTANCE: mobile station for processing one of multiple configuration of duplex communication contains a receiver, which, when functioning, receives a system information block (SIB), which includes a configuration of time division duplex communication (hereinafter – TDD) by default, and a processing scheme connected to the receiver, which, when functioning, determines TDD configuration from multiple TDD configurations, including TDD configuration by default, based on downlink control information, determines at least one serving cell, to which the mentioned specific TDD configuration must be applied, and applies the mentioned specific TDD configuration.

EFFECT: technical result is providing improved indication of configuration of time division duplex communication.

9 cl, 4 tbl, 14 dwg

Description

TECHNICAL FIELD OF THE INVENTION

The invention relates to methods for specifying an uplink / downlink configuration for time division duplex communication for a mobile station. The invention also provides a mobile station and a base station for participating in the methods described in the document.

LEVEL OF TECHNOLOGY

Long-term development of communication systems (LTE)

Third generation (3G) mobile communication systems based on WCDMA (Wideband Code Division Multiple Access) radio access technology are being deployed on a large scale around the world. The first step in expanding or evolving this technology involves the introduction of High Speed Downlink Packet Access (HSDPA) and Enhanced Uplink, also referred to as High Speed Uplink Packet Access (HSUPA), providing a highly competitive radio access technology.

To prepare for further growth in user demands and compete with new radio access technologies, the 3GPP consortium has proposed a new mobile communications system called Long Term Evolution (LTE). LTE is designed to meet the carrier needs for the transport of high-speed data and multimedia, as well as support for high-performance voice, with a focus on the next decade. The ability to deliver high bit rates is a key metric for LTE.

The 3GPP Long Term Evolution (LTE) Working Elements (WI) Specification, UMTS Enhanced Terrestrial Radio Access (UTRA) and UMTS Universal Terrestrial Radio Access Network (UTRAN), have been completed as Release 8 (LTE Rel.8). The LTE system provides efficient packet radio access and radio access networks that provide full IP functionality with low latency and low cost. In LTE, scalable multiple transmission bands are defined as 1.4, 3.0, 5.0, 10.0, 15.0, and 20.0 MHz to provide flexible system deployment using this spectrum. On the downlink, an Orthogonal Frequency Division Multiplexing (OFDM) radio access has been adopted due to its inherent multipath interference (MPI) immunity due to its low symbol rate, the use of a cyclic prefix (CP), and compatibility with different transmission band arrangements. Single Carrier Frequency Division Multiple Access (SC-FDMA) radio access has been applied on the uplink since service provision for a large coverage area took priority over increasing the peak bit rate given the limited transmit power of the user equipment (UE). Rel. 8/9 LTE uses many key packet radio access techniques, including multiple-input multiple-output (MIMO) channel transmission techniques, and implements a highly efficient control signaling structure.

LTE architecture

The general architecture is shown in Fig. 1, and a more specific representation of the E-UTRAN architecture is given in Fig. 2. The E-UTRAN consists of an Evolved Node B (eNodeB) providing E-UTRAN User Plane Protocol Terminals (PDCP / RLC / MAC / PHY) and a Control Plane (RRC) towards the UE. The eNodeB (eNB) provides a "host" for the physical (PHY), medium access (MAC), radio link control (RLC), and packet data control protocol (PDCP) layers, which include header compression and user plane encryption functionality ... It also provides radio resource control (RRC) functionality corresponding to the control plane. It performs many functions, including radio resource management, admission control (to the network), scheduling, uplink quality of service (QoS) enforcement, broadcast cell information, encryption / decryption of user and control plane data, and header compression / decompression. downlink / uplink packets in the user plane. The eNodeBs are connected to each other via an X2 interface.

The eNodeBs are also connected via an S1 interface to an Evolved Packet Core (EPC), more specifically to a mobility management module (MME) via S1-MME and to a serving gateway (SGW) via S1-U. The S1 interface supports a many-to-many relationship between MMEs / serving gateways and eNodeBs. The SGW routes and forwards user data packets, also acting as a mobility anchor for the user plane during inter-eNodeB handovers and as a mobility anchor between LTE and other 3GPP technologies (terminating for the S4 interface and relaying traffic between 2G / 3G and GW PDN systems) ... For UEs in an idle state, the SGW is the end of the downlink data path and initiates a paging call when downlink data arrives for the UE. It manages and stores user equipment contexts such as IP data service parameter information, intranet routing. It also replicates user traffic in the event of a legitimate interception.

The MME is the key control node for the LTE access network. It is responsible for tracking and paging idle UEs, including retransmissions. It takes part in the activation / deactivation of the data channel and is also responsible for the selection of the SGW for the user equipment during the initial connection and during handover within LTE, which implies a change in the location of the core network (CN) node. It is responsible for authenticating the user (by interacting with the Home Subscriber Server (HSS)). No Access Layer Signaling (NAS) ends at the MME, and it is also responsible for generating and allocating temporary credentials for UEs. It verifies the authorization of the user equipment for a standby (call) connection to the Public Land Mobile Network (PLMN) and enforces the user equipment roaming restrictions. The MME is the network endpoint for encryption / integrity protection for NAS signaling and manages the security keys (systems). The MME also supports lawful signaling interception. The MME also provides a control plane function for mobility between LTE and 2G / 3G access networks with an S3 interface terminated at the MME from the SGSN. The MME also terminates the S6a interface towards the home HSS for roaming UEs.

Component carrier structure in LTE (Version 8)

поднесущих, как также показано на Фиг.4.The downlink component carrier in 3GPP LTE (Release 8 and later) in the time-frequency domain is subdivided into so-called subframes. In 3GPP LTE (Release 8 and later), each subframe is divided into two downlink slots as shown in FIG. 3, with the first downlink slot containing a control channel area (PDCCH area) in the first OFDM symbols. Each subframe consists of a given number of OFDM symbols in the time domain (12 or 14 OFDM symbols in LTE 3GPP Release 8 and later), with each OFDM symbol spreading across the entire component carrier bandwidth. Each of the OFDM symbols thus consists of a number of modulation symbols transmitted on respective

subcarriers, as also shown in FIG. 4.

последовательных символов OFDM во временной области (например, 7 символов OFDM) и

последовательных поднесущих в частотной области, как показано на Фиг.4 (например, 12 поднесущих для компонентной несущей). В LTE 3GPP (Версии 8), блок физических ресурсов, таким образом, состоит из

ресурсных элементов, соответствующих одному временному интервалу во временной области и 180 кГц в частотной области (для получения дополнительной информации относительно ресурсной сетки нисходящей линии связи, см., например, документ TS 36.211 3GPP, "Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation (Release 8)", раздел 6.2, доступный по адресу http://www.3gpp.org и включенный в документ путем ссылки).Assuming a multi-carrier communication system such as using OFDM such as used in Long Term Evolution (LTE) 3GPP communications, the smallest resource block that can be assigned by the scheduler is a single "resource block". Physical Resource Block (PRB) is defined as

consecutive OFDM symbols in the time domain (e.g., 7 OFDM symbols) and

consecutive subcarriers in the frequency domain as shown in FIG. 4 (eg, 12 subcarriers for a component carrier). In 3GPP LTE (Release 8), the physical resource block is thus composed of

resource elements corresponding to one time slot in the time domain and 180 kHz in the frequency domain (for more information on the downlink resource grid, see, for example, 3GPP TS 36.211, "Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation (Release 8) ", Section 6.2, available at http://www.3gpp.org and incorporated by reference).

последовательным поднесущим, распространяющихся по полному подкадру, именуются "парой ресурсных блоков", или эквивалентно "парой RB" или "парой PRB". One subframe consists of two slots, so there are 14 OFDM symbols in a subframe when a so-called "regular" CP (cyclic prefix) is used, and 12 OFDM symbols in a subframe when a so-called "extended" CP is used. For terminology, in the following time-frequency resources equivalent to such

consecutive subcarriers spreading over a full subframe are referred to as "resource block pair", or equivalently "RB pair" or "PRB pair".

The term "component carrier" refers to a combination of multiple resource blocks in the frequency domain. In future versions of LTE, the term "component carrier" is no longer used; instead, the term replaces "cell", which refers to a combination of downlink and optionally uplink resources. The association between the carrier frequency for the downlink resources and the carrier frequency for the uplink resources is indicated in the system information transmitted on the downlink resources.

Similar assumptions for the component carrier structure apply to later versions as well.

Logical and transport channels

The MAC layer provides data service for the RLC layer over logical channels. Logical channels are either logical control channels that carry control data such as RRC signaling or logical traffic channels that carry user plane data. Broadcast Control Channel (BCCH), Paging Control Channel (PCCH), Common Control Channel (CCCH), Grouped Control Channel (MCCH), and Dedicated Control Channel (DCCH) are logical control channels. Dedicated Traffic Channel (DTCH) and Multicast Traffic Channel (MTCH) are information logical channels.

Data exchange from the MAC layer with the physical layer is carried out through transport channels. Data is multiplexed into transport channels depending on how it is transmitted over the air. Transport channels are classified as downlink or uplink channels as set forth below. The broadcast channel (BCH), downlink shared channel (DL-SCH), paging channel (PCH), and multicast channel (MCH) are downlink transport channels, while the uplink shared channel communication channel (UL-SCH) and random access channel (RACH) are uplink transport channels.

Multiplexing is then performed between logical channels and transport channels in the downlink and uplink, respectively.

Layer 1 / Layer 2 control signaling (L1 / L2)

To inform scheduled users of their allocation status, transport format, and other data-related information (eg, HARQ information, transmit power control (TPC) commands), L1 / L2 control signaling is transmitted on the downlink along with the data. The L1 / L2 control signaling is multiplexed with the downlink data in a subframe, assuming that the allocation for the user may vary from subframe to subframe. It should be noted that the allocation for the user can also be performed on a TTI (transmission time interval) basis, where the TTI duration can be a multiple of the number of subframes. The TTI duration can be fixed in the service area for all users, it can be different for different users, or it can even be dynamic for each user. Typically, L1 / 2 control signaling should only be transmitted once per TTI. Without loss of generality, the following assumes that the TTI is equivalent to one subframe.

L1 / L2 control signaling is transmitted on the Physical Downlink Control Channel (PDCCH). The PDCCH carries the message in the form of Downlink Control Information (DCI), which in most cases includes resource assignments and other control information for a mobile terminal or UE group. In general, multiple PDCCHs can be transmitted in one subframe.

It should be noted that in 3GPP LTE, uplink data transmission assignments, also referred to as scheduled uplink grants or uplink resource assignments, are also transmitted on the PDCCH.

Typically, information sent with L1 / L2 control signaling for uplink or downlink radio resource allocation (specifically in LTE (-A) Release 10) can be grouped into the following groups of units:

- User identification data (identifier) indicating the user who is distributable. They are usually included in the checksum by masking the CRC with the user's identity;

- Resource allocation information indicating the resources (resource blocks, RBs) to which the user is allocated. It should be noted that the number of RBs to which the user is allocated may be dynamic;

- Carrier indicator, which is used if the control channel transmitted on the first carrier assigns resources that relate to the second carrier, that is, resources on the second carrier or resources related to the second carrier;

- Modulation and coding scheme, which defines the applied modulation scheme and coding rate;

- HARQ information such as new data indicator (NDI) and / or redundancy version (RV), which is especially useful in retransmissions of data packets or portions thereof;

- Power control commands for adjusting the transmit power for the assigned data or control information transmission in the uplink;

- Reference signal information, such as applied cyclic shift and / or orthogonal coverage code index, to be used for transmitting or receiving reference signals related to the destination;

- An uplink or downlink assignment index, which is used to identify the order of assignments, which is especially useful in TDD systems;

- Information about frequency hopping, such as whether and how to apply resource frequency hopping to increase frequency diversity;

- CSI request, which is used to initiate the transmission of channel state information on the assigned resource; and

- Multicluster information, which is a flag used to indicate and control whether transmission occurs in one cluster (contiguous set of RBs) or in multiple clusters (at least two non-contiguous sets of contiguous RBs). Multi-cluster allocation was introduced with LTE- (A) 3GPP Release 10.

It should be noted that the listing above is non-exhaustive and not all of the mentioned pieces of information need to be present in every PDCCH transmission, depending on the DCI format that is used.

The downlink control information takes place in several formats that differ in overall size as well as the information contained in its fields. The various DCI formats that are currently defined for LTE are outlined below and described in detail in 3GPP TS 36.212, section 5.3.3.1 "Multiplexing and channel coding", (available at http://www.3gpp.org and included into the document by reference). For more information regarding DCI formats and the specific information that is transmitted to DCI, please refer to the technical standard or LTE - The UMTS Long Term Evolution - From Theory to Practice, ed. Stefanie Sesia, Issam Toufik, Matthew Baker, Chapter 9.3 incorporated by reference.

Format 0: DCI Format 0 is used to transmit resource grants for PUSCH using single antenna port transmissions in uplink transmission mode 1 or 2.

Format 1: DCI Format 1 is used to convey resource assignments for PDSCH transmissions in one codeword (downlink transmission modes 1, 2 and 7).

Format 1A: DCI format 1A is used to compactly signal resource assignments for PDSCH transmissions in one codeword and to allocate a special preamble signature to a mobile terminal for contention-free random access.

Format 1B: Format 1B DCI is used for compact signaling of resource assignments for PDSCH transmissions using closed-loop precoding with rank-1 transmission (coding matrix) (downlink transmission mode 6). The information transmitted is the same as in Format 1A, but with the addition of a precoding vector indicator used for PDSCH transmission.

Format 1C: Format 1C DCI is used for ultra-compact transmission of PDSCH assignments. When the 1C format is used, PDSCH transmission is limited to using Quadrature Phase Modulation (QPSK). This is used, for example, for paging signaling messages and system information broadcast messages.

Format 1D: The 1D DCI format is used for compact signaling of resource assignments for PDSCH transmission using MIMO with multi-user mode. The information transmitted is the same as in Format 1B, but instead of one of the precoding vector indicator bits, there is a single bit to indicate whether a power offset is applied to the data symbols. This function is required to indicate whether or not the transmission power is shared between two UEs. Future versions of LTE may extend this to more UE power sharing.

Format 2: DCI Format 2 is used to convey resource assignments for PDSCH for closed-loop MIMO mode of operation.

Format 2A: Format 2A DCI is used to convey resource assignments for PDSCH for open loop MIMO operation. The transmitted information is the same as for Format 2, except that if the eNodeB has two transmit antenna ports, then there is no precoding information and two bits are used to indicate the transmit rank for the four antenna ports.

Format 2B: Introduced in Version 9 and used to convey resource assignments for PDSCH for bi-layer beamforming.

Format 2C: Introduced in Version 10 and used to convey resource assignments for PDSCH for single-user or multi-user closed-loop MIMO operation using up to 8 layers.

2D format: Introduced in Version 11 and used for transmissions up to 8 levels; mainly used for COMP (Coordinated Multipoint Communication)

Format 3 and 3A: DCI formats 3 and 3A are used to transmit power control commands for PUCCh and PUSCH with 2-bit or 1-bit power controls, respectively. These DCI formats contain separate power control commands for a group of UEs.

Format 4: DCI format 4 is used for PUSCH scheduling using closed-loop spatial multiplexed transmissions in uplink transmission mode 2.

The following table gives an overview of some of the available DCI formats and typical number of bits, assuming for illustration purposes a system bandwidth of 50 RB and four antennas in the eNodeB. The number of bits indicated in the right column includes the bits for the DCI-specific CRC.

DCI format Appointment Number of bits including CRC 0 PUSCH Grants 43 one PDSCH assignments in one codeword 47 1A PDSCH Assignments Using Compact Format 43 1B PDSCH Assignments - Transfer Rank -1 46 1C PDSCH appointments using ultra-compact format 29 1D PDSCH Assignments for Multi-User MIMO 46 2 PDSCH Assignments for Closed-Loop MIMO Operation 62 2A PDSCH Assignments for Open Loop MIMO Operation 58 2B PDSCH Assignments for Dual Layer Beamforming 57 2C PDSCH assignments for single-user or multi-user MIMO operation 58 2D PDSCH assignments for single-user or multi-user MIMO closed-loop mode, COMP 61 3 Multi-user transmit power control (TPC) commands for PUCCH and PUSCH with 2-bit power controls 43 3A Multi-user transmit power control (TPC) commands for PUCCH and PUSCH with 1-bit power controls 43 four PUSCH Grants 52

FIG. 5 illustrates the processing structure for one DCI according to FIG. 5.3.3.13 in TS 36.212 GPP, as follows:

- Multiplexing information elements (refers to the multiplexing of specific information elements making up one DCI unit),

- CRC attachment

- Channel coding

- Speed negotiation

In order for the UE to identify whether it received the PDCCH transmission correctly, error detection is provided by a 16-bit CRC appended to each PDCCH (ie, DCI). In addition, the UE needs to be able to identify which PDCCH instance (s) are intended to do so. In theory, this could be done by adding an identifier to the PDCCH payload; however, it appears that it will be more efficient to scramble the "UE Identity" CRC, which saves additional overhead. The CRC can be calculated and scrambled as defined in detail by 3GPP in TS 36.212, section 5.3.3.2 "attachment CRC", hereby incorporated by reference. This section describes how error detection is provided on DCI transmissions by means of cyclic redundancy check (CRC). A brief description is given below.

All payload is used to calculate CRC parity bits. Parity bits are calculated and appended. In the case where the selection of the transmitting antenna of the UE is not configured or not applicable, after attachment, the CRC parity bits are scrambled with the corresponding radio network cell (cell) temporary identifier (RNTI).

The scrambling may further depend on the selection of the UE transmit antenna, as evident from 36.212. In the case where the UE transmit antenna selection is configured and applicable, after attachment, the CRC parity bits are scrambled with the antenna selection mask and the corresponding RNTI. Since in both cases the RNTI is included in the scrambling operation, for simplicity and without loss of generality, the following description of the embodiments simply refers to a CRC being scrambled (and descrambled, if applicable) with an RNTI, which is therefore to be understood as irrelevant, for example, a subsequent element in the scrambling process. such as an antenna selection mask.

Accordingly, the UE descrambles the CRC by applying "UE Identity" and if no CRC error is detected, the UE determines that the PDCCH carries its control information intended for it. The terminology "masking" and "unmasking" is also used for the above described CRC scrambling process with credentials.

The "UE Identity" mentioned above, with which the CRC for DCI can be scrambled, can also be SI-RNTI (Radio Network Temporary Identifier for System Information), which is not a "UE Identity" per se, but rather an identifier. associated with the type of information that is indicated and transmitted, in this case, system information. The SI-RNTI is usually specified in the datasheet and is thus known a priori to all UEs.

There are different types of RNTIs that are used for different purposes. The following tables, which are taken from Chapter 7.1 of 3GPP document 36.321, should provide an overview of the various 16-bit RNTIs and their applications.

Value (hexadecimal)

n / a

,

semi-permanent planning, temporary

,

and

(see note)

,

semi-permanent planning, temporary

,

and

Reserved for future use

Using Transport channel Logical channel Paging and system information change notification PCH PCCH Broadcasting system information DL-SCH BCCH MCCH System Information Change Notification n / a n / a Reply to a random access request DL-SCH n / a Conflict resolution (when no valid C-RNTI is available) DL-SCH CCCH Msg3 message UL-SCH CCCH, DCCH, DTCH Dynamically Scheduled Unicast UL-SCH DCCH, DTCH Dynamically Scheduled Unicast DL-SCH CCCH, DCCH, DTCH PDCCH Ordered Random Access Initiation n / a n / a Semi-permanently scheduled unicast transmission (activation, reactivation and retransmission) DL-SCH, UL-SCH DCCH, DTCH Semi-permanently scheduled unicast transmission (deactivation) n / a n / a Physical layer uplink power control n / a n / a Physical layer uplink power control n / a n / a

Physical Downlink Control Channel (PDCCH) and Physical Downlink Shared Channel (PDSCH)

The Physical Downlink Control Channel (PDCCH) carries, for example, scheduled grants for resource allocation for data transmission in the downlink or uplink.

Each PDCCH is transmitted using one or more so-called Control Channel Elements (CCEs). Each CCE corresponds to a set of Resource Elements (REs). In 3GPP LTE, currently one CCE consists of 9 Resource Element Groups (REGs, where one REG consists of four consecutive REs (frequency domain sequential), in addition to potential REs for reference signals. Resource elements occupied by reference symbols are not included in units of REG, which means that the total number of REGs in a given OFDM symbol depends on whether reference signals are present.

OFDM символах (обычно либо 1, 2, либо 3 символах OFDM, как указано посредством PCFICH (физический канал управления индикатора формата), в исключительных случаях либо 2, 3, либо 4 символах OFDM, как указывается посредством PCFICH) в подкадре, распространяющегося по всей ширине полосы пропускания системы; полоса пропускания системы обычно является эквивалентной диапазону ячейки или компонентной несущей. Диапазон, занятый первыми

OFDM символами во временной области и

поднесущими в частотной области, также именуется диапазоном PDCCH или диапазоном канала управления. Оставшиеся

символов OFDM во временной области на

поднесущих в частотной области именуются диапазоном PDSCH или диапазоном совместно-используемого канала (см. ниже).PDCCH for UE is transmitted at the first

OFDM symbols (usually either 1, 2, or 3 OFDM symbols as indicated by the PCFICH (Physical Format Indicator Control Channel), exceptionally either 2, 3, or 4 OFDM symbols as indicated by the PCFICH) in a subframe spread over the entire system bandwidth; system bandwidth is usually equivalent to the range of a cell or component carrier. Range occupied first

OFDM symbols in the time domain and

subcarriers in the frequency domain is also referred to as PDCCH band or control channel band. The remaining

OFDM symbols in the time domain by

subcarriers in the frequency domain are referred to as PDSCH band or shared channel band (see below).

For downlink assignment on a physical downlink shared channel (PDSCH), the PDCCH assigns a PDSCH resource for data (user) within the same subframe. The PDCCH control channel area in a subframe consists of a set of CCEs, where the total number of CCEs in the control area of the subframe are allocated over the entire time and frequency control resource. Multiple CCEs can be combined to effectively reduce the coding rate of the control channel. The CCEs are combined in a predetermined manner using a tree structure to achieve a different coding rate.

In LTE 3GPP PDCCH can aggregate 1, 2, 4 or 8 CCEs. The number of CCEs available for control channel assignment is a function of several factors including carrier bandwidth, number of transmit antennas, number of OFDM symbols used for control, and CCE size, etc. Multiple PDCCHs can be transmitted in a subframe.

At the transport channel layer, information transmitted over the PDCCH is also referred to as L1 / L2 control signaling. L1 / L2 control signaling is transmitted on the downlink for each user equipment (UE). The control signaling is typically multiplexed with the downlink (user) data in a subframe (assuming that the allocation for the user may vary from subframe to subframe).

Time Division Duplex - TDD

LTE can operate in Frequency Division Duplex (FDD) and Time Division Duplex (TDD) modes in a consistent infrastructure designed also to support the evolution of TD-SCDMA (Time and Frequency Division Multiple Access). TDD splits uplink and downlink transmissions in the time domain, while the frequency can remain the same.

The term "duplex" refers to bi-directional communication between two devices, other than unidirectional communication. In the bidirectional case, transmissions on the communication channel in each direction may occur simultaneously ("full duplex") or at mutually exclusive periods of time ("half duplex").

For TDD in the radio spectrum with unpaired frequencies, the basic structure of RBs and REs is depicted in FIG. 4, but only a subset of subframes of the radio frame are available for downlink transmissions; the remaining subframes are used for uplink transmissions, or for special subframes that contain a guard interval to allow switching between downlink and uplink transmissions. The guard interval allows the timing of the uplink transmission to be improved. This TDD structure is known as "Frame Structure Type 2" in 3GPP LTE Release 8 and later, which is defined as seven different configurations allowing multiple downlink / uplink relationships and periodicity hopping. 6 illustrates a Table with 7 different, indexed from 0 to 6, uplink / downlink configurations for TDD. As can be seen from it, the seven available downlink / uplink configurations for TDD can provide between 40% and 90% of the downlink subframes (assuming a dedicated subframe as a downlink subframe, since a portion of such a subframe is available for downlink transmission).

7 shows a type 2 frame structure, specifically for a switching point periodicity of 5 ms, that is, configurations 0, 1, 2 and 6 for TDD.

7 illustrates a radio frame having a duration of 10 ms and corresponding to two half-frames of 5 ms each. The radio frame consists of 10 subframes of 1 ms, where each of the subframes is assigned the type "Uplink", "Downlink" or "Special", as defined by the table of FIG. 6, where "D" means "Downlink", U stands for Uplink and S stands for Ad Hoc.

As can be appreciated from FIG. 6, subframe # 1 is always a Custom subframe, and subframe # 6 is a Custom subframe for configurations 0, 1, 2, and 6 in TDD; for configurations 3, 4, and 5 in TDD, subframe # 6 is for Downlink. Special subframes include three fields: DwPTS (Downlink Pilot Time Slot), GP (Guard Time), and UpPTS (Uplink Pilot Time Slot). The following Table shows information about a special subframe and in specific lists - DwPTS (Downlink Pilot Time Slot), GP (Guard Period) and UpPTS (Uplink Pilot Time Slot) durations as a multiple of the sampling time T _s = (1/30720) ms as specified for LTE 3GPP Release 11.

Custom subframe configuration Downlink Conventional Cyclic Prefix Downlink extended cyclic prefix Dwpts UpPTS Dwpts UpPTS Uplink Conventional Cyclic Prefix Uplink Extended Cyclic Prefix Uplink Conventional Cyclic Prefix Uplink Extended Cyclic Prefix 0 6592 T _s 2192 T _s 2560 T _s 7680 T _s 2192 T _s 2560 T _s one 19760 T _s 20480 T _s 2 21952 T _s 23040 T _s 3 24144 T _s 25600 T _s four 26336 T _s 7680 T _s 4384 T _s 5120 T _s five 6592 T _s 4384 T _s 5120 T _s 20480 T _s 6 19760 T _s 23040 T _s 7 21952 T _s 12800 T _s eight 24144 T _s - - - nine 13168 T _s - - -

The TDD configuration applied in the system affects many operations performed at the mobile station and base station such as radio resource management (RRM) measurements, channel status information (CSI) measurements, channel estimates, PDCCH and HARQ detection timing. ...

Specifically, the UE reads system information to find out the TDD configuration in its current cell, that is, which subframe to monitor for measurement, for CSI sampling and reporting, for time domain filtering to obtain a channel estimate, for PDCCH detection, or for feedback on acknowledgment / non-acknowledgment (ACK / NACK) in UL / DL.

Lack of existing semi-static UL / DL configuration in TDD

LTE TDD currently allows asymmetric UL-DL allocations by providing seven different semi-statically configurable uplink / downlink configurations. The existing mechanism for accommodating the UL-DL allocation is based on a system information collection procedure or a system information change procedure, where the UL-DL configuration in TDD is indicated by a system information block (SIB), specifically the TDD-config configuration parameter in SIB1, (regarding broadcasting details of the system For information, see 3GPP TS 25.331, "Radio Resource Control (RRC)" version 6.7.0, section 8.1.1, incorporated by reference; available at http://www.3gpp.org).

With the System Information Change Procedure in Version 8, the supported timeline for UL / DL TDD reconfiguration is every 640 ms or more. When reusing ETWS (Earthquake and Tsunami Warning System), the supported timeline for reconfiguring UL-DL TDD is every 320 ms or more depending on the default configured paging cycle.

Semi-static allocation of UL / DL TDD configuration may or may not correspond to an instantaneous traffic situation. However, it will be useful to tailor the UL / DL TDD configuration to current traffic needs; for example, to dynamically create more "empty" uplink subframes to mitigate interference with respect to transmission, for example, in the uplink or downlink of a neighboring cell. Accordingly, Version 12 is expected to approve more dynamic UL / DL TDD reconfiguration.

The 3GPP Consortium announced a study objective in TR 36.828 v1 1.0.0 to investigate the timelines for different types of UL / DL TDD configuration changes and their advantages and disadvantages. In general, the conclusion of the study problem showed that faster UL / DL TDD reconfiguration timelines provide more benefits than slower UL / DL TDD reconfiguration timelines. In addition, the scope of required changes to the description varies depending on the supported reconfiguration timelines.

The research objective, however, also identified problems regarding legacy UEs (UE instances compatible only with standards prior to Release 12 that do not implement a TDD dynamic reconfiguration mechanism) arising from different TDD configurations for different UEs. In particular, it is considered that if the base station desires to dynamically reconfigure TDD configuration for UEs in a cell, dynamic TDD reconfiguration can only be properly handled by new UEs; in case a non-existing SIB-based TDD configuration indication method is used, but a more dynamic indication method, incumbent UEs will not apply TDD reconfiguration. Therefore, incumbent UEs will still assume the presence of reference signals such as CRS (Common Reference Symbol) in the downlink subframes in the radio frame according to the default TDD configuration (ie, indicated by the SIB). In case the dynamic TDD configuration has an uplink subframe instead of a downlink subframe, the incumbent UE will thus mistakenly believe that a CRS should be present, which can lead to incorrect channel measurements and estimates.

The research objective also looked at RRC, MAC and PHY signaling as more dynamic indication methods. Reconfiguring UL / DL TDD by RRC signaling is on the order of 200 ms and requires a reconfiguration message per RRC connected user, unless a broadcast or multicast method is specified. Reconfiguring UL / DL TDD by signaling the MAC sub-layer Control Element (CE) in the MAC header is in the order of several tens of ms. Using a Physical Layer design such as provided by L1 / L2 control signaling in DCI, a UL / DL TDD adaptation time scale of about 10 ms can be achieved.

In view of the results of the above study task, UL / DL TDD reconfiguration should be performed as quickly as possible, thus allowing flexible adaptation of the UL / DL TDD configuration to traffic situations.

SUMMARY OF THE INVENTION

One aspect of the invention is to provide an improved TDD configuration indication that addresses the problems of the prior art as discussed above. Dynamic adaptation of the TDD configuration of one or more radio frames will preferably be possible.

The problem is solved according to the object of the independent claims. Useful embodiments are the subject of the dependent claims.

According to various embodiments of the invention, a time division duplex (TDD) configuration to be used for transmission between a mobile station and a base station is encoded by the base station into DCI transmission to the mobile station. In this context, the term "DCI transmission" is to be understood as an integral transmission, which in this case means DCI and the corresponding error detection-capable code (such as CRC). The invention provides various embodiments of how this can be achieved.

According to the first aspect of the invention, the TDD configuration is encoded into an error detection code computed for the DCI; more specifically, a specific TDD configuration is implicitly encoded into error detection code. For each of the assigned TDD configurations, a different ID value is set, and the mobile stations and base stations know predetermined ID values and relationships with possible TDD configurations. More specifically, in LTE communication systems, the identifier may be a temporary radio network identifier having a length of 16 bits, which is then scrambled with a 16-bit error detection code (CRC).

Accordingly, when the base station desires to dynamically change the default TDD configuration to a different TDD target configuration for a specific cell, it will generate DCI, calculate the corresponding error detection code for the DCI, and then scramble the computed CRC with the identifier associated with the TDD target configuration that the mobile station (s) in this cell should use for the next radio frame (s).

DCI as such (i.e., not a CRC) can either be in the DCI format already defined in the LTE standards, or is equivalent to having the same size as an already defined DCI format, such as Format 1C, or it can conform to a "new" DCI format which serves the purpose of being used in conjunction with dynamic TDD reconfiguration.

In case DCI already defined in LTE is used (such as 1C format), then the base station can set one or more parameters in DCI (in the case of 1C format, resource block assignment, for example) to an invalid value, so that the mobile station processing the DCI and the invalid parameter can easily determine that the received DCI is not the DCI of the "legacy" Format 1C assigning downlink resources, but is more preferably used to transmit the TDD configuration for dynamic TDD reconfiguration.

The first aspect can be further improved in that the above invalid parameter of a given DCI Format (eg, DCI Format 1C) can be used to encode an additional parameter, as will be explained. It is allowed that an invalid parameter can take not only one invalid value, but various invalid values. In the mentioned case, the invalid parameter can be used to encode an indicator that the DCI (with said invalid parameter) carries the dynamic TDD reconfiguration, as well as to encode an additional parameter (value). Specifically, the fact that the parameter is set to any invalid value or group of such allows the mobile station to determine that the DCI will be the DCI carrying the TDD configuration indicator rather than the traditional DCI. Then, each (or group) of invalid values of said parameter can then be associated with a different value of another specific parameter. For example, the actually available invalid values may be associated with other TDD configurations such that the invalid parameter, and specifically one of the invalid parameter values, also indicates the desired TDD configuration index for dynamic UL / DL TDD reconfiguration.

In addition, the DCI format already defined in 3GPP can be reused, namely, assuming the bit size is the same as the already defined DCI, but specifying different content (information elements) within the DCI for specific situations. For example, the 1C DCI format in TS 36.212 of the 3GGP standard can be extended so that for one set of cases, the 1C DCI format is used as already specified by 3GPP (for PDSCH assignments), but for the remaining (other) cases, the 1C DCI format is not the same as implies the current 3GPP (as defined at the time of filing, respectively) and is intended to dynamically reconfigure TDD according to the invention.

As a third alternative, a new DCI format may be specified, possibly of a different length than existing DCI formats; the length depends on the additional content (parameters) to be included in the said new DCI format. As will be explained in further detail below, in any case ("predefined", "predefined-extended" and "new" DCI), the DCI may include at least one additional parameter that can be used advantageously in conjunction with dynamic reconfiguration. TDD.

In accordance with the above, the mobile station receiving the DCI and the corresponding error detection code will attempt to descramble and perform error checking on the error detection code using different identifiers predetermined for different TDD configurations. When the mobile station successfully checks for errors with one of the various candidate identifiers, the mobile station will then determine the specific TDD configuration associated with the identifier for which the error check was successful. The mobile station then knows the TDD configuration to be applied for the next radio frame (s) in its cell.

In addition, the mobile station can determine the aforementioned additional parameter (s) to gain additional benefits; details are provided in the detail description section.

According to the second aspect of the invention, instead of implicitly encoding the TDD configuration into an error detection code as in the first aspect, the TDD configuration is directly encoded as a parameter in the DCI. Accordingly, the DCI generated by the base station contains a field (preferably up to 3 bits long) indicating the TDD configuration to be used instead of the default TDD configuration. The second aspect of the invention further describes that the error detection code calculated for the DCI and transmitted along with the DCI from the base station to the mobile station is scrambled with a cell ID, which allows the mobile station to identify a target cell to which the TDD configuration is to be applied.

The mobile station, upon receiving the DCI and the scrambled error detection code from the base station, first performs an error check on the error detection code and DCI, which includes the step of descrambling the error detection code. The mobile station performs error checking until it determines the cell ID actually used for the error detection code scrambling process at the base station.

From the determined cell ID, the mobile station firstly learns that the DCI is a DCI for transporting a TDD configuration (and not some other kind of DCI); second, the mobile station knows for which target cell (identified by the cell ID) the TDD configuration (included in the DCI) is actually supposed to be applied. From the DCI payload, the mobile station learns the TDD configuration.

Naturally, a mobile station applies a specific TDD configuration only if it belongs to a specific target cell identified by the cell ID used to scramble the DCI error detection code.

The second aspect can be used advantageously for a scenario in which there is one macro cell and different small cells; for example, a macro cell is operated with frequency division duplex, and small cells are operated with time division duplex. The mobile station is in the macro cell as well as the small cell. It is believed that the DCI (and error correction code) is transmitted from the base station of the macro cell, but for the purpose of dynamically changing the TDD configuration of one (or more) small cells.

To this end, the cell ID used to scramble the DCI error detection code can only identify one of the cells for which the new TDD configuration is to be applied. Alternatively, different small cells can be grouped together and associated with a single cell (group) identifier, so that upon receipt of the DCI and error detection code scrambled with said single cell (group) identifier, mobile stations can determine which cell (s) the new a TDD configuration should and should not be applied.

Although, as explained above, using such a cell ID to scramble the error detection code already allows the mobile station to identify the DCI that will carry the TDD configuration, the DCI may further contain an invalid parameter to reduce the risk of a false alarm. Specifically, when the base station generates DCI for dynamically changing the TDD configuration of one (or more) cells, the TDD configuration parameter is turned on, and the DCI parameter is set to an invalid value. Which specific parameters should be invalidated is less important if only the mobile station can identify said invalidation parameter and thus infer that the DCI is not "traditional" DCI, but some carrying TDD configuration. Accordingly, the mobile station may infer from both the cell ID used in connection with the error detection code and the invalid DCI parameter that the DCI should additionally contain an indication of the new TDD configuration to be applied.

One example of an invalid parameter is the Resource Block Assignment parameter in DCI Format 1C as defined by 3GPP. The resource block assignment parameter is set to an invalid value, for example, all "1".

As already explained in connection with the first aspect of the invention, the above invalid parameter can also be used to encode additional information; for example, an optional parameter value. If a plurality of invalid values are available for an invalid parameter, then all invalid values are associated with information that the DCI carrying said invalid parameter is a DCI carrying one of the plurality of TDD configurations. On the other hand, each (or group) of invalid values is associated with a different value for another parameter. Thus, additional information can be transported to the mobile station without using additional bits. For example, the actual TDD configuration may be encoded into an invalid parameter; at least seven different invalid parameter values must be available to distinguish between the seven TDD configurations. Then, based on the specific invalid parameter value used in the DCI, the mobile station can determine the specific TDD configuration.

Instead of adopting a known DCI Format (such as DCI Format 1C defined by 3GPP), it is also possible to define a new DCI Format for the sole purpose of transporting a TDD dynamic reconfiguration indication, and possibly additional additional parameters, as discussed in more detail below.

According to the third aspect of the invention, the TDD configuration is encoded directly into DCI, similar to the second aspect of the invention. The DCI further comprises an invalid parameter that allows the mobile station to detect that the received DCI carries a TDD configuration indicator. Accordingly, in case the mobile station determines that the DCI contains said specific invalid parameter, it proceeds to determine the specific TDD configuration contained in the DCI.

With respect to the third aspect of the invention, it is believed that any of the various known DCI Formats defined by 3GPP may be used, eg, DCI Format 1C already discussed for the first and second aspects of the invention. However, other formats may be used instead.

The 1C DCI format, as defined by 3GPP, traditionally includes a Resource Block Assignment (RBA) parameter for PDSCH assignment. For purposes of the third aspect, said RBA parameter may be set to an invalid value.

As with the previous aspects, additional information can be encoded into said invalid parameter if there are a number of invalid values for the invalid parameter. Whereas any of the invalid values indicates that the DCI (carrying said invalid parameter) is used for the purpose of transporting the TDD configuration, each (or group) of invalid values is associated with additional information. For example, the actual TDD configuration may be encoded into an invalid parameter; at least seven different invalid parameter values must be available to distinguish between the seven TDD configurations. Then, based on the specific invalid parameter value used in the DCI, the mobile station can determine the specific TDD configuration.

A further improvement of the third aspect allows the error detection code for the DCI to be scrambled with a so-called system information identifier (SI-RNTI in 3GPP). SI-RNTI is commonly used in 3GPP systems to transport system information, and various SI windows are set so that the mobile station can determine which system information message in which SI window to indicate (compare 3GPP TS 36.331, sections 5.2.1.2 and 5.2.3 ). According to 3GPP, only one SI message can be sent per SI window, but multiple times in that SI window (if necessary). Since different SI messages can be configured with different intervals, it is possible that some SI windows are not used for any SI message; in other words, the mobile station is aware that in such unused SI windows, any transmission of the SI message will not be performed by the base station. This knowledge of the mobile station is used to its advantage either by transmitting DCI transporting the TDD configuration in such an unused SI window, although the CRC for DCI is scrambled with SI-RNTI. Reception within the unused SI window allows the mobile station, in combination with the invalid parameter, to determine with higher confidence that the DCI is transporting the TDD configuration.

As a modification, the TDD-DCI reception window is set, which is to be understood as limiting where the mobile station expects the TDD-DCI message for exactly specific subframes and / or radio frames. In other words, the preferably periodic nature of the subframes and / or radio frames is defined as a TDD-DCI receive window where the TDD configuration message can be transmitted by the base station and / or only needs to be received and detected by the mobile station.

A first embodiment of the present invention provides a method for specifying one of a plurality of time division duplex, TDD, configurations for a mobile station in a communication system. The TDD configuration defines uplink subframes, downlink subframes, and special subframes in one or more radio frames. The mobile station receives from the base station downlink control information and a corresponding error detection code of the downlink control information, the error detection code being scrambled by the base station with an identifier associated with the TDD configuration. Then, the mobile station determines the identifier used to scramble the error detection code of the downlink control information. The mobile station determines the TDD configuration from the identifier used to scramble the error detection code of the downlink control information.

According to a useful modification of the first embodiment of the invention, which may be used in addition to or alternatively to the above, each TDD configuration is associated with a different identifier value, and a particular TDD configuration is encoded into an error detection code by scrambling the error detection code with an associated identifier. In one embodiment, the identifier is a 16-bit temporary radio network identifier.

According to a useful modification of the first embodiment of the invention, which can be used in addition to or alternatively to the above, the relationship between the plurality of TDD configurations and identifiers is predetermined in the base station, and the mobile station is informed of the predetermined communication by a configuration message.

According to a useful modification of the first embodiment of the invention, which can be used in addition to or alternatively to the above, the communication system is an LTE communication system, and the downlink control information is downlink control information in the 1C format. For this particular case, in a further embodiment, the downlink control information further comprises an invalid parameter indicating that the downlink control information indicates one of a plurality of TDD configurations. The invalid parameter may be a resource block assignment parameter having a length of 3-9 bits and an invalid value, such as all bits of the resource block assignment parameter being "1".

According to a useful modification of the first embodiment of the invention, which can be used in addition to or alternatively to the above, the downlink control information contains an invalid parameter with one of a plurality of invalid values. All of the plurality of invalid values indicate that the downlink control information indicates one of the plurality of TDD configurations. On the other hand, each or group of invalid invalid parameter values indicate at least one of the following:

the target cell for which the TDD configuration is to be applied,

a HARQ instruction to restart or not restart the HARQ protocol of the mobile station for communication upon application of the said TDD configuration, for the cell to which the TDD configuration is to be applied,

an action time parameter for said TDD configuration, such that the mobile station determines the amount of time during which said TDD configuration is to be applied from an action time parameter, preferably, the active time parameter indicates an index associated with a predetermined amount of time,

a buffer status reporting procedure instruction instructing to cancel the current buffer status reporting procedure or initiate a new buffer status reporting procedure upon applying the specified TDD configuration,

a scheduling request procedure instruction instructing to cancel the current scheduling request procedure or initiate a new scheduling request procedure upon applying the specified TDD configuration,

a random channel access procedure instruction instructing to cancel the current random channel access procedure or initiate a new random channel access procedure, upon applying the specified TDD configuration,

an instruction for generating a power headroom report instructing to cancel the current generation of a power headroom report or initiate a new generation of a power headroom report upon applying the specified TDD configuration.

According to a useful modification of the first embodiment of the invention, which can be used in addition to or alternatively to the above, the downlink control information comprises at least one of the following:

a target cell identifier identifying a target cell for which the TDD configuration is to be applied, preferably wherein the target cell identifier is 1-5 bits long,

a HARQ instruction including an instruction to restart or not restart the HARQ protocol of the mobile station for communication for the cell to which the TDD configuration is to be applied upon applying said TDD configuration, preferably wherein the HARQ instruction is 1 bit long,

the action time parameter for said TDD configuration is such that the mobile station determines the amount of time during which said TDD configuration is to be applied from the action time parameter, preferably the action time parameter is 1 to 2 bits long and indicates an index associated with a predetermined the amount of time

a padding field with a bit value such that the mobile station determines whether the bit value of the padding field is the same as a predetermined bit value, preferably the additional field is 1-32 bits long,

a buffer status reporting procedure instruction instructing to cancel the current buffer status reporting procedure or initiate a new buffer status reporting procedure upon applying the specified TDD configuration,

a scheduling request procedure instruction instructing to cancel the current scheduling request procedure or initiate a new scheduling request procedure upon applying the specified TDD configuration,

a random channel access procedure instruction instructing to cancel the current random channel access procedure or initiate a new random channel access procedure, upon applying the specified TDD configuration,

an instruction for generating a power headroom report instructing to cancel the current generation of a power headroom report or initiate a new generation of a power headroom report upon applying the specified TDD configuration.

According to a useful modification of the first embodiment of the invention, which can be used in addition to or alternatively to the above, the mobile station is configured with a default TDD configuration. The mobile station applies a specific TDD configuration for n + m radio frames and applies a default TDD configuration for n + m + 1 radio frames. m> = 1, and n is associated with a radio frame in which the downlink control information and error detection code are received by the mobile station.

A first embodiment of the present invention provides a mobile station for processing one of a plurality of time division duplex, TDD, configurations in a communication system. The TDD configuration defines uplink subframes, downlink subframes, and special subframes in one or more radio frames. A receiving section of the mobile station receives downlink control information and a corresponding error detection code for downlink control information from the base station. The error detection code is scrambled by the base station with an identifier associated with the TDD configuration. The processor of the mobile station determines the identifier used to scramble the error detection code of the downlink control information. The mobile station processor further determines the TDD configuration from the identifier used to scramble the error detection code of the downlink control information.

According to a useful modification of the first embodiment of the invention, which can be used in addition to or alternatively to the above, the receiver receives from the base station information about the relationship between the plurality of TDD configurations and identifiers.

According to a useful modification of the first embodiment of the invention, which can be used in addition to or alternatively to the above, the communication system is an LTE communication system, and the downlink control information is downlink control information in the 1C format. In this case, the processor can determine that the downlink control information indicates one of a plurality of TDD configurations from the downlink control information containing an invalid parameter. In one design, the invalid parameter is a resource block assignment parameter having a length of 3-9 bits and an invalid value, such as all bits of the resource block assignment parameter being "1".

According to a useful modification of the first embodiment of the invention, which may be used in addition to or alternatively to the above, the downlink control information contains an invalid parameter with one of a plurality of invalid values. The mobile station processor determines that the downlink control information indicates one of a plurality of TDD configurations based on any of the invalid values. In addition, the processor determines, based on the specific invalid value of the invalid parameter in the downlink control information, at least one of the following:

a target cell for which the TDD configuration is to be applied;

a HARQ instruction to restart or not restart the HARQ protocol of the mobile station for communication for the cell to which the TDD configuration is to be applied upon applying said TDD configuration,

an action time parameter indicating the amount of time during which said TDD configuration is to be applied, preferably wherein the action time parameter indicates an index associated with a predetermined amount of time,

a buffer status reporting procedure instruction instructing to cancel the current buffer status reporting procedure or initiate a new buffer status reporting procedure upon applying the specified TDD configuration,

a scheduling request procedure instruction instructing to cancel the current scheduling request procedure or initiate a new scheduling request procedure upon applying the specified TDD configuration,

a random channel access procedure instruction instructing to cancel the current random channel access procedure or initiate a new random channel access procedure, upon applying the specified TDD configuration,

an instruction for generating a power headroom report instructing to cancel the current generation of a power headroom report or initiate a new generation of a power headroom report upon applying the specified TDD configuration.

According to a useful modification of the first embodiment of the invention, which may be used in addition to or alternatively to the above, the mobile station processor determines from the downlink control information at least one of the following:

a target cell identifier identifying a target cell for which the TDD configuration is to be applied, preferably wherein the target cell identifier is 1-5 bits long,

a HARQ instruction including an instruction to restart or not restart the HARQ protocol of the mobile station for communication for the cell to which the TDD configuration is to be applied upon applying said TDD configuration, preferably wherein the HARQ instruction is 1 bit long,

an action time parameter for said TDD configuration, from which the processor is adapted to determine the amount of time during which said TDD configuration should be applied, preferably wherein the action time parameter is 1 to 2 bits long and indicates an index associated with a predetermined amount of time,

the bit value of the padding field, such that the mobile station determines whether the bit value of the padding field is the same as a predetermined bit value, preferably wherein the additional field is 1-32 bits long,

a buffer status reporting procedure instruction instructing to cancel the current buffer status reporting procedure or initiate a new buffer status reporting procedure upon applying the specified TDD configuration,

a scheduling request procedure instruction instructing to cancel the current scheduling request procedure or initiate a new scheduling request procedure upon applying the specified TDD configuration,

a random channel access procedure instruction instructing to cancel the current random channel access procedure or initiate a new random channel access procedure, upon applying the specified TDD configuration,

an instruction for generating a power headroom report instructing to cancel the current generation of a power headroom report or initiate a new generation of a power headroom report upon applying the specified TDD configuration.

According to a useful modification of the first embodiment of the invention, which can be used in addition to or alternatively to the above, the mobile station is configured with a default TDD configuration. The processor applies a specific TDD configuration for n + m radio frames, and applies a default TDD configuration for n + m + 1 radio frames, where m> = 1 and n is associated with a radio frame in which downlink control information and error detection code are received by the mobile station.

A first embodiment of the present invention provides a base station for indicating one of a plurality of time division duplex, TDD, configurations to a mobile station in a communication system. The TDD configuration defines uplink subframes, downlink subframes, and special subframes in one or more radio frames. The base station processor makes a TDD configuration decision and generates downlink control information and a corresponding error detection code for the downlink control information. The processor additionally scrambles the generated error detection code with an identifier associated with the specific TDD configuration. The transmitter transmits the generated downlink control information and the scrambled error detection code to the mobile station.

A second embodiment of the present invention provides a method for specifying one of a plurality of time division duplex, TDD, configurations for a mobile station for at least one target cell in a communication system. The TDD configuration defines uplink subframes, downlink subframes, and special subframes in one or more radio frames. The mobile station receives downlink control information and a corresponding error detection code for the downlink control information from the base station of the first cell. The downlink control information error detection code is scrambled by the base station with a target cell ID associated with at least one target cell to which the TDD configuration is to be applied. The mobile station determines the identifier used to scramble the error detection code of the downlink control information. The mobile station also determines the TDD configuration from the downlink control information in case the specific identifier is a target cell identifier, and determines at least one target cell to which the specific TDD configuration should be applied from the target cell identifier used for scrambling. downlink control information error detection code.

According to a useful modification of the second embodiment of the invention, which can be used in addition to or alternatively to the above, the first cell is operated in the frequency division duplex mode, and the at least one target cell is operated in the TDD mode. Downlink control information and error detection code are transmitted by the base station from the first cell.

According to a useful modification of the second embodiment of the invention, which can be used in addition to or alternatively to the above, the target cell ID either identifies a single target cell or a group of target cells from all cells. According to a useful modification of the second embodiment of the invention, which can be used in addition to or alternatively to the above, the communication system is an LTE communication system, and the downlink control information is downlink control information in 1C format. In a particular embodiment, the downlink control information further comprises an invalid parameter indicating that the downlink control information indicates one of a plurality of TDD configurations. The invalid parameter may be a resource block assignment parameter having a length of 3-9 bits and an invalid value, such as all bits of the resource block assignment parameter being "1".

According to a useful modification of the second embodiment of the invention, which can be used in addition to or alternatively to the above, the downlink control information contains an invalid parameter with one of a plurality of invalid values. All of the plurality of invalid values indicate that the downlink control information indicates one of the plurality of TDD configurations. On the other hand, each or group of invalid invalid parameter values indicates at least one of the following:

TDD configuration,

a HARQ instruction to restart or not restart the HARQ protocol of the mobile station for communication for the cell to which the TDD configuration is to be applied upon applying said TDD configuration,

an action time parameter for said TDD configuration, such that the mobile station determines the amount of time during which said TDD configuration is to be applied from an action time parameter, preferably, the active time parameter indicates an index associated with a predetermined amount of time,

a buffer status reporting procedure instruction instructing to cancel the current buffer status reporting procedure or initiate a new buffer status reporting procedure upon applying the specified TDD configuration,

a scheduling request procedure instruction instructing to cancel the current scheduling request procedure or initiate a new scheduling request procedure upon applying the specified TDD configuration,

a random channel access procedure instruction instructing to cancel the current random channel access procedure or initiate a new random channel access procedure, upon applying the specified TDD configuration,

an instruction for generating a power headroom report instructing to cancel the current generation of a power headroom report or initiate a new generation of a power headroom report upon applying the specified TDD configuration.

According to a useful modification of the second embodiment of the invention, which can be used in addition to or alternatively to the above, wherein the downlink control information comprises at least one of the following:

a TDD configuration field indicating the TDD configuration, preferably wherein the TDD configuration field is 3 bits long,

a HARQ instruction including an instruction to restart or not restart the HARQ protocol of the mobile station for communication for the cell to which the TDD configuration is to be applied upon applying said TDD configuration, preferably wherein the HARQ instruction is 1 bit long,

an action time parameter for said TDD configuration such that the mobile station determines the amount of time during which said TDD configuration is to be applied from an action time parameter, preferably wherein the action time parameter is 1 to 2 bits long and indicates an index associated with a predetermined the amount of time

a padding field with a bit value such that the mobile station determines whether the bit value of the padding field is the same as a predetermined bit value, preferably the additional field is 1-32 bits long,

a buffer status reporting procedure instruction instructing to cancel the current buffer status reporting procedure or initiate a new buffer status reporting procedure upon applying the specified TDD configuration,

a scheduling request procedure instruction instructing to cancel the current scheduling request procedure or initiate a new scheduling request procedure upon applying the specified TDD configuration,

a random channel access procedure instruction instructing to cancel the current random channel access procedure or initiate a new random channel access procedure, upon applying the specified TDD configuration,

an instruction for generating a power headroom report instructing to cancel the current generation of a power headroom report or initiate a new generation of a power headroom report upon applying the specified TDD configuration.

According to a useful modification of the second embodiment of the invention, which can be used in addition to or alternatively to the above, the mobile station is configured with a default TDD configuration and applies a specific TDD configuration for n + m radio frames, and applies a default TDD configuration for n + m + 1 radio frames. ... m> = 1, and n is associated with a radio frame in which the downlink control information and error detection code are received by the mobile station.

A second embodiment of the present invention provides a mobile station for processing one of a plurality of time division duplex, TDD, configurations in a communication system. The TDD configuration defines uplink subframes, downlink subframes, and special subframes in one or more radio frames. The receiving section of the mobile station receives downlink control information and a corresponding error detection code for the downlink control information. The downlink control information error detection code is scrambled by the base station with a target cell ID associated with at least one target cell to which the TDD configuration is to be applied. The processor of the mobile station determines the identifier used to scramble the error detection code of the downlink control information. The processor determines the TDD configuration from the downlink control information in the case that the determined identifier is the identifier of the target cell. The processor determines at least one target cell to which the specific TDD configuration is to be applied from the target cell ID used to scramble the error detection code for the downlink control information.

According to a useful modification of the second embodiment of the invention, which can be used in addition to or alternatively to the above, the communication system is an LTE communication system, and the downlink control information is downlink control information in 1C format. The processor determines that the downlink control information indicates one of a plurality of TDD configurations from the downlink control information containing an invalid parameter. The invalid parameter may be a resource block assignment parameter having a length of 3-9 bits and an invalid value, such as all bits of the resource block assignment parameter being "1".

According to a useful modification of the second embodiment of the invention, which can be used in addition to or alternatively to the above, the downlink control information contains an invalid parameter with one of a plurality of invalid values. The processor determines that the downlink control information indicates one of a variety of TDD configurations based on any of the invalid values. The processor determines, based on the specific invalid invalid parameter value in the downlink control information, at least one of the following:

TDD configuration,

a HARQ instruction to restart or not restart the HARQ protocol of the mobile station for communication for the cell to which the TDD configuration is to be applied upon applying said TDD configuration,

an action time parameter indicating the amount of time during which said TDD configuration is to be applied from an action time parameter, preferably wherein the action time parameter indicates an index associated with a predetermined amount of time,

a buffer status reporting procedure instruction instructing to cancel the current buffer status reporting procedure or initiate a new buffer status reporting procedure upon applying the specified TDD configuration,

a scheduling request procedure instruction instructing to cancel the current scheduling request procedure or initiate a new scheduling request procedure upon applying the specified TDD configuration,

a random channel access procedure instruction instructing to cancel the current random channel access procedure or initiate a new random channel access procedure, upon applying the specified TDD configuration,

an instruction for generating a power headroom report instructing to cancel the current generation of a power headroom report or initiate a new generation of a power headroom report upon applying the specified TDD configuration.

According to a useful modification of the second embodiment of the invention, which may be used in addition to or alternatively to the above, the processor determines from the downlink control information at least one of the following:

a TDD configuration from a TDD configuration field, preferably wherein the TDD configuration field is 3 bits long,

a HARQ instruction including an instruction to restart or not restart the HARQ protocol of the mobile station for communication for the cell to which the TDD configuration is to be applied upon applying said TDD configuration, preferably wherein the HARQ instruction is 1 bit long,

an action time parameter for said TDD configuration, from which the processor is adapted to determine the amount of time during which said TDD configuration should be applied, preferably wherein the action time parameter is 1 to 2 bits long and indicates an index associated with a predetermined amount of time,

the bit value of the padding field, such that the mobile station determines whether the bit value of the padding field is the same as a predetermined bit value, preferably wherein the additional field is 1-32 bits long,

a buffer status reporting procedure instruction instructing to cancel the current buffer status reporting procedure or initiate a new buffer status reporting procedure upon applying the specified TDD configuration,

a scheduling request procedure instruction instructing to cancel the current scheduling request procedure or initiate a new scheduling request procedure upon applying the specified TDD configuration,

a random channel access procedure instruction instructing to cancel the current random channel access procedure or initiate a new random channel access procedure, upon applying the specified TDD configuration,

an instruction for generating a power headroom report instructing to cancel the current generation of a power headroom report or initiate a new generation of a power headroom report upon applying the specified TDD configuration.

According to a useful modification of the second embodiment of the invention, which can be used in addition to or alternatively to the above, the mobile station is configured with a default TDD configuration. The processor applies a specific TDD configuration for n + m radio frames, and applies a default TDD configuration for n + m + 1 radio frames, where m> = 1 and n is associated with the radio frame, where the downlink control information and error detection code are received by the mobile station ...

A second embodiment of the present invention provides a base station for indicating one of a plurality of time division duplex, TDD, configurations to a mobile station in a communication system. The TDD configuration defines uplink subframes, downlink subframes, and special subframes in one or more radio frames. The base station processor decides on the TDD configuration. The processor generates the downlink control information and the corresponding error detection code for the downlink control information, the downlink control information indicates the decision TDD configuration. The processor scrambles the generated error detection code with a target cell ID associated with at least one target cell to which the TDD configuration is to be applied. The transmitter transmits the generated downlink control information and the scrambled error detection code to the mobile station.

A third embodiment of the present invention provides a method for specifying one of a plurality of time division duplex, TDD, configurations for a mobile station in a communication system. The TDD configuration defines uplink subframes, downlink subframes, and special subframes in one or more radio frames. The mobile station receives downlink control information from the base station, wherein the downlink control information indicates a TDD configuration and further comprises an invalid parameter indicating that the downlink control information indicates one of a plurality of TDD configurations. The mobile station determines if the received downlink control information contains an invalid parameter. The mobile station determines the TDD configuration from the downlink control information in case the received downlink control information contains an invalid parameter.

According to a useful modification of the third embodiment of the invention, which may be used in addition to or alternatively to the above, the communication system is an LTE communication system, and the downlink control information is downlink control information in 1C format, the invalid parameter being a resource block assignment parameter, having a length of 3-9 bits and an invalid value, such as all bits of the resource block assignment parameter equal to "1".

According to a useful modification of the third embodiment of the invention, which can be used in addition to or alternatively to the above, the invalid parameter can take on one of a plurality of invalid values. All of the set of invalid values indicate that the downlink control information indicates one of a plurality of TDD configurations, and each or group of invalid values indicates at least one of the following:

TDD configuration

target cell identifier identifying the target cell to which the TDD configuration is to be applied

a HARQ instruction to restart or not restart the HARQ protocol of the mobile station for communication for the cell to which the TDD configuration is to be applied upon applying said TDD configuration

an action time parameter for said TDD configuration, such that the mobile station determines the amount of time during which said TDD configuration is to be applied from an action time parameter, preferably, the active time parameter indicates an index associated with a predetermined amount of time,

a buffer status reporting procedure instruction instructing to cancel the current buffer status reporting procedure or initiate a new buffer status reporting procedure upon applying the specified TDD configuration,

a scheduling request procedure instruction instructing to cancel the current scheduling request procedure or initiate a new scheduling request procedure upon applying the specified TDD configuration,

a random channel access procedure instruction instructing to cancel the current random channel access procedure or initiate a new random channel access procedure, upon applying the specified TDD configuration,

an instruction for generating a power headroom report instructing to cancel the current generation of a power headroom report or initiate a new generation of a power headroom report upon applying the specified TDD configuration.

According to a useful modification of the third embodiment of the invention, which may be used in addition to or alternatively to the above, the downlink control information comprises at least one of the following:

a TDD configuration field indicating the TDD configuration, preferably wherein the TDD configuration field is 3 bits long,

a target cell identifier identifying a target cell for which the TDD configuration is to be applied, preferably wherein the target cell identifier is 1-5 bits long,

a HARQ instruction including an instruction to restart or not restart the HARQ protocol of the mobile station for communication for the cell to which the TDD configuration is to be applied upon applying said TDD configuration, preferably wherein the HARQ instruction is 1 bit long,

an action time parameter for said TDD configuration, such that the mobile station determines the amount of time during which said TDD configuration is to be applied from an action time parameter, preferably the action time parameter is 1 to 2 bits long and indicates an index associated with a predetermined the amount of time

a bit value padding field such that the mobile station determines whether the bit value of the padding field is the same as a predetermined bit value, preferably wherein the additional field is 1-32 bits long,

a buffer status reporting procedure instruction instructing to cancel the current buffer status reporting procedure or initiate a new buffer status reporting procedure upon applying the specified TDD configuration,

a scheduling request procedure instruction instructing to cancel the current scheduling request procedure or initiate a new scheduling request procedure upon applying the specified TDD configuration,

a random channel access procedure instruction instructing to cancel the current random channel access procedure or initiate a new random channel access procedure, upon applying the specified TDD configuration,

an instruction for generating a power headroom report instructing to cancel the current generation of a power headroom report or initiate a new generation of a power headroom report upon applying the specified TDD configuration.

According to a useful modification of the third embodiment of the invention, which may be used in addition to or alternatively to the above, the mobile station receives from the base station an error detection code for the received downlink control information, wherein the error detection code for the downlink control information is scrambled by the base station with an identifier system information. The predefined receiving windows for system information are uniquely associated with specific system information messages. The mobile station receives the downlink control information and the corresponding error detection code scrambled with the system information identifier within one of said system information reception windows, which is not used by the base station to transmit the system information as a result of the configured periodicities for the system information messages.

According to a useful modification of the third embodiment of the invention, which can be used in addition to or alternatively to the above, the mobile station is configured with a default TDD configuration. The mobile station applies a specific TDD configuration for n + m radio frames, and applies a default TDD configuration for n + m + 1 radio frames, where m> = 1 and n is associated with a radio frame in which downlink control information and error detection code are received mobile station.

A third embodiment of the present invention provides a mobile station for processing one of a variety of time division duplex (TDD) communication configurations in a communication system. The TDD configuration defines uplink subframes, downlink subframes, and special subframes in one or more radio frames. The receiving section of the mobile station receives downlink control information from the base station, wherein the downlink control information indicates a TDD configuration and further comprises an invalid parameter indicating that the downlink control information indicates one of a plurality of TDD configurations. The mobile station processor determines whether the received downlink control information contains an invalid parameter. The processor further determines the TDD configuration from the downlink control information in case the received downlink control information contains an invalid parameter.

According to a useful modification of the third embodiment of the invention, which can be used in addition to or alternatively to the above, the communication system is an LTE communication system, and the downlink control information is downlink control information in the 1C format. An invalid parameter is a resource block assignment parameter having a length of 3-9 bits and an invalid value, such as all bits of the resource block assignment parameter equal to "1".

According to a useful modification of the third embodiment of the invention, which can be used in addition to or alternatively to the above, the invalid parameter can take on one of a plurality of invalid values. The processor determines that the downlink control information indicates one of a variety of TDD configurations based on any of the invalid values. The processor determines at least one of the following based on the specific invalid value of the invalid downlink control information parameter:

TDD configuration,

target cell identifier identifying the target cell for which the TDD configuration is to be applied,

a HARQ instruction including an instruction to restart or not restart the mobile station's HARQ protocol for communication for a cell to which the TDD configuration is to be applied upon applying said TDD configuration,

an action time parameter indicating the amount of time during which said TDD configuration is to be applied from an action time parameter, preferably wherein the action time parameter indicates an index associated with a predetermined amount of time,

a buffer status reporting procedure instruction instructing to cancel the current buffer status reporting procedure or initiate a new buffer status reporting procedure upon applying the specified TDD configuration,

a scheduling request procedure instruction instructing to cancel the current scheduling request procedure or initiate a new scheduling request procedure upon applying the specified TDD configuration,

a random channel access procedure instruction instructing to cancel the current random channel access procedure or initiate a new random channel access procedure, upon applying the specified TDD configuration,

an instruction for generating a power headroom report instructing to cancel the current generation of a power headroom report or initiate a new generation of a power headroom report upon applying the specified TDD configuration.

According to a useful modification of the third embodiment of the invention, which may be used in addition to or alternatively to the above, the processor determines from the downlink control information at least one of the following:

a TDD configuration from a TDD configuration field, preferably wherein the TDD configuration field is 3 bits long,

a target cell identifier identifying a target cell for which the TDD configuration is to be applied, preferably wherein the target cell identifier is 1-5 bits long,

a HARQ instruction including an instruction to restart or not restart the HARQ protocol of the mobile station for communication for the cell to which the TDD configuration is to be applied upon applying said TDD configuration, preferably wherein the HARQ instruction is 1 bit long,

an action time parameter for said TDD configuration, from which the processor is adapted to determine the amount of time during which said TDD configuration should be applied, preferably wherein the action time parameter is 1 to 2 bits long and indicates an index associated with a predetermined amount of time,

the bit value of the padding field such that the mobile station determines whether the bit value of the padding field is the same as a predetermined bit value, preferably wherein the additional field is 1-32 bits long,

a buffer status reporting procedure instruction instructing to cancel the current buffer status reporting procedure or initiate a new buffer status reporting procedure upon applying the specified TDD configuration,

a scheduling request procedure instruction instructing to cancel the current scheduling request procedure or initiate a new scheduling request procedure upon applying the specified TDD configuration,

a random channel access procedure instruction instructing to cancel the current random channel access procedure or initiate a new random channel access procedure, upon applying the specified TDD configuration,

an instruction for generating a power headroom report instructing to cancel the current generation of a power headroom report or initiate a new generation of a power headroom report upon applying the specified TDD configuration.

According to a useful modification of the third embodiment of the invention, which can be used in addition to or alternatively to the above, the receiving section receives from the base station an error detection code for the received downlink control information, wherein the error detection code for the downlink control information is scrambled by the base station with an identifier system information. The predefined receiving windows for system information are uniquely associated with specific system information messages. The receiving section receives the downlink control information and the corresponding error detection code scrambled with the system information identifier within one of said system information receive windows, which is not used by the base station to transmit the system information as a result of the configured periodicities for the system information messages.

According to a useful modification of the third embodiment of the invention, which can be used in addition to or alternatively to the above, the mobile station is configured with a default TDD configuration. The processor applies a specific TDD configuration for n + m radio frames, and applies a default TDD configuration for n + m + 1 radio frames, where m> = 1 and n is associated with the radio frame, where the downlink control information and error detection code are received by the mobile station ...

A third embodiment of the present invention provides a base station for specifying one of a plurality of time division duplex, TDD, configurations for a mobile station in a communication system, the TDD configuration specifying uplink subframes, downlink subframes, and special subframes in one or more radio frames. The base station processor decides on the TDD configuration. The processor generates downlink control information and a corresponding error detection code for the downlink control information, the downlink control information indicates the TDD configuration of the decision made and includes an invalid parameter indicating that the downlink control information indicates one of a plurality of TDD configurations ... The base station transmitter transmits the generated downlink control information to the mobile station.

BRIEF DESCRIPTION OF DRAWINGS

In the following, the invention is described more specifically with reference to the accompanying figures and drawings.

1 shows an exemplary architecture of a 3GPP LTE system,

2 shows an exemplary overview of a generic E-UTRAN architecture in 3GPP LTE,

3 shows exemplary subframe boundaries on a downlink component carrier as defined for 3GPP LTE (Release 8/9),

4 illustrates an exemplary downlink resource grid for a downlink timeslot as defined for 3GPP LTE (Release 8/9),

5 illustrates a processing structure for downlink single control information as defined by 3GPP,

6 shows seven currently standardized configurations 0-6 for UL / DL TDD, the respective definitions of 10 subframes and their hopping point periodicity,

7 is an illustration of the structure of a radio frame composed of two half frames and 10 subframes for a switching point periodicity of 5 ms,

FIG. 8 illustrates seven currently standardized configurations 0-6 for UL / DL TDD of FIG. 6, and exemplary connectivity with seven TDD-RNTIs according to the first embodiment,

9 is an illustration of a basic block diagram for an operation of a mobile station according to a first embodiment of the invention,

FIG. 10 illustrates seven currently standardized configurations 0-6 for UL / DL TDD of FIG. 6, and exemplary connectivity with seven values of the TDD configuration indicator according to the second and third embodiment,

11 is a schematic illustration of a multi-small cell and one macro-cell scenario called an enhanced Local Area.

12 is an illustration of a basic block diagram for an operation of a mobile station according to a second embodiment,

13 is an illustration of a basic block diagram for an operation of a mobile station according to a third embodiment, and

14 shows two radio frames with different UL / DL TDD configurations along with some timing for data and feedback transmissions.

DETAILED DESCRIPTION OF THE INVENTION

Various embodiments of the invention will be described in the following paragraphs. For illustrative purposes only, most embodiments are outlined in terms of a radio access scheme in accordance with the 3GPP LTE (Release 8/9) and LTE-A (Release 10/11/12) mobile communication systems discussed in part in the Background section above. ... It should be noted that the invention can advantageously be used, for example, in a mobile communication system such as LTE-A 3GPP communication systems (Release 10/11/12) as described in the Background section above, but the invention is not limited to its use in these specific exemplary communication networks.

The term "TDD configuration" refers to the uplink / downlink configuration in TDD as defined in the current standard, where the TDD configuration specifies, for each subframe of a radio frame, whether it is a downlink, uplink, or special subframe. The term "TDD configuration index" is a number (currently 0-6) respectively associated with one of the seven possible UL / DL TDD configurations and defined in the 3GPP technical standards (see FIG. 6).

The term "default TDD configuration" as used in the claims and throughout the specification refers to a TDD configuration that is configured "semi-statically" in the system using SIB1 as explained in the prior art section. In another formulation, the default TDD configuration is such that one TDD configuration broadcasts to all UEs in the base station's communication area using a conventional mechanism for collecting and modifying system information. Of course, the "default TDD configuration" can also be changed during communication, although not as dynamically as with the present invention, but over an extended operating period.

The term "scrambling" as used in the claims in connection with error detection code and used in the detailed description of the invention mainly in connection with CRC (as an example of error detection code), refers to the process of implicitly encoding, for example, an identifier into error detection code (CRC). The term "masking" is considered equivalent in this application.

The term "invalid parameter" as used in the claims and description is to be understood broadly as a parameter having an invalid value, thus constituting an invalid parameter.

In the following, several embodiments of the invention will be explained in detail. The explanations are not to be understood as limiting the invention, but simply as examples of embodiments of the invention for a better understanding of the invention. A person skilled in the art should be aware that the general principles of the invention, as set forth in the claims, may be applied to various scenarios and methods that are not explicitly described in the document. Accordingly, the following scenarios, intended for purposes of explaining various embodiments, will not limit the invention as such.

Various embodiments explained for the invention generally relate to TDD configurations, and in particular provide a quick mechanism for dynamically changing a TDD configuration from a default TDD configuration (configured by SIB) to a target TDD configuration.

As explained in the prior art section, the prior art semi-static TDD configuration reconfiguration is slow and cumbersome and will be improved by a dynamic process according to one of the various embodiments explained below.

Three subsequent embodiments use DCI transmission from a base station to indicate a TDD configuration change for one or more cells. The TDD configuration can either be implicitly encoded into said transmission (in a CRC, as for the first embodiment), or more directly as a parameter of the DCI part (as for the second and third embodiments), or encoded in a transport block that is indicated by the DCI.

First embodiment

According to a first set of embodiments of the invention, the TDD configuration is encoded into a CRC for DCI, and both are transmitted (usually broadcast) from a base station for a particular radio cell.

For this purpose, definitions of seven different RNTIs are defined, for example, at a base station or other entity in the network, with each of the seven different RNTIs associated with one of seven TDD configurations such that each TDD configuration 0-6 is associated with one different RNTI. 8 illustrates an example relationship where TDD_0-6_RNTI values are associated with TDD configurations. The RNTI cost is thus strictly limited to the number of TDD configurations, and, for example, is not related to the number of small cells in an eLA scenario (see second embodiment below). The RNTIs for TDD are preferably 16-24 bits long and can be freely selectable, but are preferably selected from the range of FFEO-FFFCs in hexadecimal notation for the 16-bit case and can be indicated in a manner similar to what is currently done for M-RNTI, P-RNTI , SI-RNTI, or determined and configured by the base station and transmitted to the receivers of the mobile devices through the transmission of RRC configuration messages or system information.

In one modification of the first embodiment (which also applies to the second and third embodiments), not all seven TDD configurations are to be linked. In this case, there is no need for seven different RNTIs, and for example, four TDD-RNTIs are sufficient to distinguish between the required TDD configurations that will be available for dynamic TDD reconfiguration according to the invention.

Relationships "TDD-RNTI - TDD configuration" can be indicated in the same way as currently M-RNTI, P-RNTI, SI-RNTI, or determined and configured by the base station and transmitted to the mobile station (s); and possibly to the base station (s), if the decision is made by another network entity. This can be done in various other ways, and the particular method used is not critical to the operation of the invention. For example, the table relationship in FIG. 8 may be transmitted using RRC messages, system information messages, or may be generated during connection setup. Accordingly, both the base station and the mobile station have information necessary to implement dynamic TDD reconfiguration according to the first embodiment.

The base station may decide at some point in time that the default TDD configuration is not optimal and that another TDD configuration would be more beneficial. This could be due, for example, to a different traffic situation or similar circumstances. The base station thus decides a target TDD configuration (from the remaining six TDD configurations available) other than the default TDD configuration, and performs dynamic TDD reconfiguration as described below.

The base station, after deciding on a new TDD configuration for specific cell (s), generates DCI (a new or known format, or a known format, but in the form of an extension to it, see below), and then calculates an error detection code (3GPP uses CRC as error detection code) for the generated DCI. In the prior art, the CRC would be scrambled with any of different RNTIs, depending on the type of DCI being transmitted. In this case, the CRC calculated for the DCI is scrambled with the TDD-RNTI associated with a specific TDD target configuration, for example, TDD_1_RNTI for TDD configuration 1 (see FIG. 8; and provided that the default TDD configuration is not 1 TDD). The actual scrambling of the CRC and RNTI TDD can be performed in the usual manner as is well known in the art and explained in the background section as an example for 3GPP LTE.

After the base station has generated the DCI, calculated the CRC, and scrambled the CRC with the corresponding TDD RNTI, the DCI and the scrambled CRC are transmitted in the cell. The DCI / CRC message can be sent on a PDCCH or ePDCCH, and preferably in a common search space, in case many or all of the mobile stations are to be informed of the reconfiguration. In other cases, transmission in a UE-specific search space may be more efficient as the transmission parameters may be tailored to the intended recipient and the corresponding prevailing transmission conditions.

According to one modification of the embodiment, one of the already available downlink control information messages, as defined by 3GPP and briefly discussed in the background section, is reused for said purpose. In other words, the base station reuses one of Formats 0, 1, 1A, 1B, 1C, 1D, 2, 2A, 2B, 2C DCI, 2D, 3, 3A, 4 (as defined at the time of this application; or any other format defined by 3GPP in the future) to dynamically reconfigure TDD instead of the actual intended purpose of a specific DCI message.

For example, a Format 1C DCI message that has the least number of bits of all available DCI formats may be reused. It should be noted that although the following description is also generally for the second and third embodiments, the 1C format for DCI is used to illustrate the principles of the invention, other DCI formats may be reused for purposes of the invention.

The 1C DCI format in 3GPP is defined to include the following fields:

- Resource block assignment (RBA) 3-9 bits (depending on the bandwidth)

- Modulation and Coding Scheme (MCS) 5 bits

- indicator of the value of the guard interval 1 bit (only if the bandwidth> = 50 PRB)

A more specific discussion of the contents of DCI Format 1C can be found in Chapter 5.3.3.1.4 of 3GPP TS 36.212, hereby incorporated by reference. Thus, a 1C DCI message can be between 8 and 15 bits in length.

Accordingly, instead of sending the above parameters for PDSCH assignment as intended for DCI Format 1C, the base station may include other parameters in the DCI. This is partly dependent on the bandwidth in the cell, as the number of bits available in DCI Format 1C is bandwidth dependent. These other parameters to be included in DCI Format 1C may contain at least one of the following:

- target cell identifier identifying the target cell for which the TDD configuration implicitly encoded in the DCI CRC is to be applied,

- a HARQ instruction to instruct the mobile station (s) to restart or not restart the HARQ protocol upon applying the new TDD configuration,

- an action time parameter for an encoded TDD configuration indicating to the mobile station (s) the amount of time that said TDD configuration should be applied before switching back to the default TDD configuration,

- a padding field with a predefined bit value (virtual CRC) that can be used to "pad" the DCI so that the remaining otherwise unused bits are useful to reduce the risk of a false alarm

- a buffer status reporting (BSR) procedure instruction instructing to cancel the pending BSR procedure or initiate a new BSR procedure when the specified TDD configuration is applied,

- a scheduling request (SR) procedure instruction instructing to cancel the pending SR procedure or initiate a new SR procedure upon application of the specified TDD configuration,

- a random access channel (RACH) procedure instruction to cancel a pending RACH procedure or initiate a new RACH procedure upon application of the specified TDD configuration,

- a Power Headroom Report (PHR) instruction instructing to cancel the pending PHR or initiate a new PHR upon applying the specified TDD configuration.

These parameters are only briefly discussed above for purposes of illustration and will be explained in more detail below.

When using such a known DCI format, it is also possible to set one of the parameters set for said known DCI format to an invalid value for the base station and thus use the invalid parameter as a "hop code point" to indicate to the mobile station that the DCI carrying invalid parameter, not normal, but carries a UL / DL TDD configuration indicator. The DCI message thus includes said special (invalid) parameter, in the form of a normal DCI message, but with an invalid value. This invalid value is known to both the base station and the mobile station. Taking the already standardized 1C DCI format as an example, the resource block assignment parameter may be set to an invalid value such as all bit values are "1".

An invalid value for a parameter or combination of parameters can usually be characterized as representing a state that is reserved or does not meet the requirements for the specified parameter. For example, an invalid resource block assignment value is one that will result in the assignment of at least one resource block with a negative index or at least one resource block outside of the available resource blocks. Another example of an invalid value relates to the HARQ process number parameter in the case of TDD with an HARQ index, which indicates the HARQ process outside the specified maximum number of HARQ processes, as indicated in Table 7-1 in 3GPP TS 36.213. An example of a combination of invalid parameters, where the value represents a reserved state, is 'precoding information' as available, for example, in DCI format 2, where depending on the number of specified transport blocks, different values of the precoding information are defined as 'reserved', and where the number of the specified transport blocks depends on the combination of the specified modulation and coding scheme and redundancy version as specified in chapter 7.1.7.2 in 3GPP TS 36.213.

For resource allocation type 2, at least one RBA state is invalid for all downlink PRB bands 6-110, namely when all bit values are set to "1". For 10 and 13 PRBs there is exactly one invalid state, already mentioned all bits = 1. For 6 PRBs there are 2 invalid RBA values. There are 4 invalid RBA values for 15 PRBs. There are 50 invalid RBA values for 25 PRBs. For 50 PRBs, there are 62 invalid RBAs for slot 1 and 83 invalid RBAs for slot 2. For 75 PRBs, there are 120 invalid RBAs, and for 100 and 110 PRBs, there are 212 invalid RBAs.

Specifically, if there is a frequency band where there is more than one invalid value (i.e., all but 10 and 13 PRBs, which, however, are less important in practice), additional information may be encoded into this invalid DCI parameter in addition to indicating that The DCI carrying the invalid parameter carries the UL / DL TDD configuration indicator. The additional information may be one of the aforementioned other parameters, namely, at least one of target cell ID, HARQ instruction and action time parameter, BRS instruction, SR instruction, RACH instruction, and PHR instruction. Of course, if one of these parameters is encoded into an invalid parameter, then the DCI should not include said specific parameter separately in its payload.

For example, considering a bandwidth of 15 PRBs with 4 invalid RBA values, all of the 4 invalid RBA values indicate to the mobile station that the DCI carrying said invalid RBA value includes an indicator regarding the dynamic TDD configuration. In addition, each particular invalid RBA value can further associate with one different action time parameter (e.g., 10ms, 40ms, 100ms, and 200ms), or differentiate between different target cells for which the TDD configuration is to be applied (e.g. PCell, SCell1, SCell2 or SCell3).

Alternatively, 2 of the invalid RBA values are associated with a "restart HARQ" instruction, and the remaining 2 invalid RBA values are associated with a "do not restart HARQ" instruction. Similar considerations apply for other frequency bands; for example, when only 2 invalid states are available for an RBA parameter, then only two different states for additional information can be encoded, such as a HARQ instruction, or an action time parameter (eg, distinguishing between valid periods of 10 ms and 40 ms).

As an alternative to reusing the known DCI format (such as Format 1C), it is also possible to create an extension of the known DCI format so that the known DCI format is used only for specific cases, and a different "version" of the known DCI format is used for other specific cases. For example, it will be possible to adapt a known DCI format (such as Format 1C) to be applicable only for specific radio frames or subframes within specific radio frames, and include a definition that specifies a known DCI format to be used for dynamic UL / DL reconfiguration. TDD, for other radio frames or other subframes within specific radio frames, where, depending on the "version", the DCI format can contain different information elements.

Alternatively to the above, it is also possible to use a DCI format specially defined for the purpose of dynamic TDD reconfiguration; for example, also having a different size than the already defined DCI formats. In this case, the number of DCI bits does not depend on the cell bandwidth, but can be set freely depending on the parameters to be transmitted in this new DCI. For example, DCI Format 1E may be defined, which includes at least one of the above parameters (target cell ID, HARQ instruction, validity time parameter, padding field, BSR instruction, SR instruction, RACH instruction, PHR instruction).

So, the base station transmits the DCI and the scrambled CRC in its cell, and the mobile station (s) in the cell receive the DCI and the scrambled CRC. DCI and CRC processing according to this first embodiment is explained in conjunction with FIG. 9, which shows a block diagram of a mobile station for the main first embodiment of the invention.

The mobile station listens on the PDCCH and EPDCCH to detect DCI messages destined for the mobile station. After receiving the DCI and CRC from the base station, the mobile station proceeds to determine the RNTI with which the CRC was scrambled. Specific error checking and descrambling can be performed in the usual manner, as discussed for examples in the 3GPP LTE art section. For example, the mobile station performs error checking for DCI based on CRC, DCI, and various possible candidate identifiers that may have been used to scramble the DCI from among the seven TDD RNTIs. For only one of the RNTIs, the CRC by the mobile station is successful. Thus, the mobile station determines that one particular TDD RNTI was used for scrambling.

The mobile station then proceeds to determine which TDD configuration a particular TDD RNTI is associated with, for example, by referring to a table as defined in FIG. 8. Thus, for example, the mobile station determines to switch to TDD configuration 1 instead of continuing to use the default TDD configuration.

The TDD configuration thus determined is then applied by the mobile station for a specific time. This can either be preset to be a fixed amount of time, such as 1, 2, or 4 radio frames. Alternatively, the time can be specified dynamically, for example using the validity parameter already mentioned earlier as (optionally) being part of the DCI payload or encoded into an invalid parameter (see above). Assuming that the mobile station receives the DCI / CRC transmission in radio frame n, it then processes the DCI and CRC accordingly and applies said TDD configuration for a specific number of radio frames n + 1, n + 2, n + 3, etc., depending on from the action time parameter from the DCI or a predefined fixed amount of time. After the dynamically indicated TDD configuration "expires", that is, is no longer applied, the mobile station switches back to the default TDD configuration until, for example, it receives another TDD DCI for dynamic UL / DL TDD reconfiguration.

Alternatively, the mobile station may also transition to applying a new TDD configuration until it accepts another TDD reconfiguration; in other words, the new TDD configuration is not indicated for a specific amount of time, but indefinitely, unless otherwise specified.

The mobile station can also determine additional parameters from the DCI depending on whether the DCI includes those. For example, the mobile station may determine the target cell, the HARQ instruction, the action time parameter, the padding field value, the BRS instruction, the SR instruction, the RACH instruction, and / or the PHR instruction therefrom.

The details of how the information extracted from these additional parameters is used are explained separately below in connection with these parameters.

According to a further modification of the first embodiment, the CRC from the DCI is scrambled by a TDD-RNTI, although only one TDD-RNTI will need to be specified for this purpose instead of multiple TDD-RNTIs, where the DCI assigns physical resources to transmit a transport block in a manner such as currently, 1A DCI format can be used to assign physical resources for a transport block. Said transport block may then represent a MAC or RRC message that contains TDD (re-) configuration information and parameters, as outlined in the following sections of this application. In other words, instead of (or in addition to) using the DCI payload to indicate one or more TDD configuration parameters, RNTI is used to identify that a reconfiguration message is being transmitted, and the DCI payload provides information about the transport block that carries the TDD configuration parameter (s). ...

Second embodiment

The second embodiment of the invention is mainly different from the first embodiment explained above in that the UL / DL TDD configuration is not encoded in the RNTI used to scramble the DCI CRC, but instead the UL / DL TDD configuration indicator is included in the DCI payload. Most of the remaining details, however, remain the same between the first and second embodiments.

The DCI UL / DL TDD Configuration Indicator distinguishes between 7 different UL / DL TDD configurations in FIG. 6; thus, a 3-bit field is sufficient to indicate a particular UL / DL TDD configuration, where each pointer value is associated with one of the TDD configurations. Again, it is also possible to distinguish between fewer UL / DL TDD configurations so that a 2-bit (or even 1-bit) field is already sufficient; however, with the disadvantage that dynamic TDD reconfiguration is not as flexible.

The relationship between 3-bit values and TDD configurations can be set by the base station or other network entity. An exemplary relationship for all seven TDD configurations using a 3-bit TDD indicator field is illustrated in FIG. 10. Information on the relationship between the TDD configuration indicator values and the actual TDD configurations is reported to the mobile station; and possibly to the base station (s), if the decision is made by another network entity. As in the case of the first embodiment, the informing procedure can be carried out in various ways; for example, using RRC messages, system information messages, or may be done during connection setup. Accordingly, both the base station and the mobile station have the necessary information to implement the dynamic TDD reconfiguration of the invention.

With regard to the first embodiment, the base station decides to change the UL / DL TDD configuration from the default TDD configuration to another TDD target configuration, for example, because the TDD target is better suited to current traffic. The base station thus desires to perform dynamic TDD reconfiguration and generates a DCI including the above UL / DL TDD configuration indicator.

The base station thus generates a DCI for dynamic TDD reconfiguration, wherein the DCI includes a TDD configuration indicator indicating the TDD configuration that the base station has decided on. Also, as already explained in detail for the first embodiment, the DCI may include additional parameters such as at least one of a HARQ instruction, an action time parameter, an additional field, a BRS instruction, an SR instruction, a RACH instruction, and an instruction PHR.

In the same way as for the first embodiment, the DCI generated by the base station may be one of the downlink control information messages already available as defined by 3GPP (e.g., DCI Formats 0, 1, 1A, 1B, 1C, 1D, 2, 2A , 2B, 2C, 2D, 3, 3A, 4). In this case, instead of sending the normal parameters of the specified DCI Format (such as RBA, MCS, Format 1C slot value indicator), the base station includes other parameters. As explained above, the TDD configuration indicator field is included.

When using a known DCI format for a base station, it is also possible to invalidate one of the parameters set for said known DCI. The invalid parameter indicates to the mobile station that the DCI carrying the invalid parameter further carries the UL / DL TDD configuration indicator. This has been explained in detail for the first embodiment, and the same principles apply to the second embodiment as well and are not repeated for the sake of brevity. Instead, the reader is kindly indicated by relevant extracts from the first embodiment.

In addition, an invalid parameter can not only be understood as indicating to the mobile station that the DCI carries the UL / DL TDD reconfiguration indicator, but this invalid parameter may encode an additional parameter, such as a specific UL / DL TDD reconfiguration indicator, or any of the other parameters mentioned. above: HARQ instruction, action time parameter, BRS instruction, SR instruction, RACH instruction, PHR instruction. This is very similar to using the invalid parameter for the first embodiment, except that the invalid parameter for the first embodiment may encode the target cell ID but not the TDD configuration indicator, whereas it is different for the second embodiment.

As an alternative to reusing a known DCI format (such as 1C format), it is also possible to create an extension of a known format, as already explained for the first embodiment. To avoid repetition, the reader is referred to the relevant sections of the first embodiment.

As a further alternative, it is also possible to use a DCI format specifically defined for the purpose of dynamically reconfiguring TDD, for example with a different size. Again, the reader is referred to the relevant sections of the first embodiment.

Regardless of the actual DCI format used and whether or not the DCI includes additional parameters, the base station calculates an error detection code for the similarly generated DCI. According to a second embodiment, an error detection code (CRC) is then scrambled with a cell ID identifying the target cell (s) for which TDD dynamic reconfiguration is to be applied. The cell ID may also be referred to as SC-RNTI, small cell RNTI.

Since the cell ID for CRC scrambling is considered to have the same length as the CRC, that is, it is expected to be 16-24 bits long, it is especially suitable for distinguishing many different cells, and thus can preferably be used in scenarios where there is many hundreds. The 16-24 bit cell ID values can flexibly associate with either single cells or a different group of cells. This has the advantage that the base station can flexibly perform TDD reconfiguration for either single cells (eg, SCell1) and / or a group of cells (eg, neighboring cells SCell1-SCell10) by using a specific target cell ID value associated with it. In addition, one of the available target cell IDs can also identify all cells as target cells. The decision on the relationship between the target cell ID values and the target cell (group) can be made in the base station or other network entity, and then must be reported to the mobile station (and the base station), so that both the base station and the mobile station have the same information. necessary for dynamic TDD reconfiguration according to the second embodiment. With regard to the first embodiment, it is not possible to use all the available RNTI values (65536 different values are available for the 16-bit RNTI case) since some of them are already reserved for other purposes. Alternatively, the relationships can be predefined and fixed according to the standard.

Existing mechanisms such as carrier indicator fields only support 8 different cells at most. LTE-Advanced will, however, support an Extended Local Area (eLA), where many tens of small cells can be located in the coverage area of a macro cell. This is schematically illustrated in FIG. 11, where a large-area macrocell operates at about 800 MHz and in which many small-area cells operate at about 3.4 GHz. In such a cell deployment, a mobile station may need to distinguish more than 7 small cells, especially if the mobile station is moving through the coverage area of a macro cell and must perform radio measurements on multiple small cells to determine the one with the most favorable radio conditions.

So, the base station transmits the DCI and the scrambled CRC for the DCI, and the mobile stations located in the cell receive the DCI and the scrambled CRC. DCI and CRC processing in the mobile station according to the second embodiment will be explained with reference to FIG. 12.

The mobile station listens on the PDCCH and EPDCCH to detect DCI messages destined for the mobile station. Thus, the mobile station receives the DCI and CRC from the base station and determines the RNTI with which the CRC was scrambled. Specific error checking and descrambling may be performed in the usual manner, as described illustratively in the prior art section regarding 3GPP LTE. For example, the mobile station performs error checking for DCI based on CRC, DCI, and various possible candidate identifiers that may have been used to scramble the DCI from among these target cell identifiers. For only one of the RNTIs, the CRC by the mobile station is successful. Thus, the mobile station determines that one of the specific target cell identifiers has been used for scrambling.

From the fact that the target cell ID was used for CRC scrambling, the mobile station may already infer that the DCI further indicates a TDD configuration for performing dynamic TDD reconfiguration. Accordingly, the mobile station then proceeds to determine the specific DCI-encoded TDD configuration in one of various ways, as explained above. Thus, the mobile station can either read the actual value of the TDD configuration indicator field as shown in FIG. 10 and associate the value with the corresponding TDD configuration; or the mobile station determines the value of the invalid parameter and determines the associated TDD configuration from the value of the invalid parameter.

In addition, the mobile station determines from the determined target cell ID a specific target cell or group of cells for which the encoded TDD configuration is intended and should be applied. The TDD reconfiguration should be applied by the mobile station only if the mobile station actually belongs to the identified target cell. Otherwise, TDD reconfiguration may be ignored by the mobile station.

If included in the DCI, the mobile station can determine additional parameters from the DCI payload, for example, an action time parameter, a HARQ instruction, a padding field value, a BRS instruction, an SR instruction, a RACH instruction, and / or a PHR instruction. The details of how the information extracted from these additional parameters is used are explained separately below in connection with these parameters.

The TDD configuration thus determined is then applied by the mobile station for a specific time. As in the case of the first embodiment, this can either be preset to be a fixed amount of time, such as 1, 2, or 4 radio frames. Alternatively, the time can be indicated dynamically, for example by using the action time parameter already mentioned earlier as being (optionally) part of the DCI payload or being encoded into an invalid parameter (see above). Assuming that the mobile station receives the DCI / CRC transmission in radio frame n, it then processes the DCI and CRC accordingly and applies said TDD configuration for a specific number of radio frames n + 1, n + 2, n + 3, etc., depending on from the action time parameter in DCI or a predefined fixed amount of time. After the dynamically indicated TDD configuration "expires", that is, is no longer applied, the mobile station switches back to the default TDD configuration until, for example, it receives another DCI TDD for dynamic UL / DL TDD reconfiguration.

Alternatively, the mobile station may also transition to applying a new TDD configuration until it accepts another TDD reconfiguration; in other words, the new TDD configuration is not indicated for a specific amount of time, but indefinitely until instructed otherwise.

According to a modification of the second embodiment, the CRC for the DCI is scrambled according to the SC-RNTI, and the DCI assigns physical resources for transmission of the transport block in a similar manner as, for example, the existing DCI format 1A can be used to assign physical resources for the transport block. Said transport block may then represent a MAC or RRC message that contains TDD (re) configuration information and parameters, such as the required TDD configuration, or target cell index, or other parameters outlined in the following sections of this application.

Third embodiment

The third embodiment of the invention is similar to the first and second embodiments in that it deals with dynamic reconfiguration of UL / DL TDD using DCI / CRC transmission. Moreover, like the second embodiment, the UL / DL TDD configuration is not implicitly encoded in the RNTI used for CRC scrambling, but is instead included in the DCI payload. However, according to the third embodiment, the target cell identifier (SC-RNTI) is not used for scrambling the DCI CRC. However, the DCI includes an invalid parameter to indicate to the mobile station that the DCI further comprises an indicator regarding the TDD configuration. In other words, an invalid parameter already discussed in connection with the first and second embodiments as being an optional DCI parameter for the third embodiment is always included in the DCI payload.

Otherwise, many of the details already discussed for the first and second embodiments remain the same for the third embodiment. For this reason, repetition is avoided as much as possible, and the reader is referred to the corresponding excerpts of the first and / or second embodiment.

In the same way as for the second embodiment, the DCI UL / DL TDD configuration indicator distinguishes all 7 different UL / DL TDD configurations in FIG. 6; or alternatively, fewer UL / DL TDD configurations can be distinguished. Accordingly, the UL / DL TDD configuration indicator may be defined as exemplarily depicted in FIG. 10. To avoid repetition, the reader is referred to the sections of the second embodiment explaining in detail the UL / DL TDD configuration indicator; which can be included as a separate parameter in the DCI payload, or can be encoded into an invalid parameter when enough invalid values are available, as explained earlier. In any case, both the base station and the mobile station should have a common understanding of how different TDD configurations can be indicated using DCI.

As already discussed for the first and second embodiments, the base station at some point in time may decide to change the UL / DL TDD configuration from the default TDD configuration to another UL / DL TDD configuration, for example, because the TDD configuration is better suited to the current traffic. The base station thus desires to perform dynamic TDD reconfiguration, as will be explained below in connection with the third embodiment.

The base station generates the DCI, the DCI including a TDD configuration indicator for indicating the TDD configuration that the base station has decided on. As explained for the first and second embodiments in detail, the DCI may further include additional parameters; for this particular third embodiment: target cell ID, HARQ instruction, action time parameter, padding field, BRS instruction, SR instruction, RACH instruction, and / or PHR instruction.

Since the DCI according to the third embodiment always includes an invalid parameter, the base station-generated DCI must be one of the downlink control information messages already available as defined by 3GPP (e.g., Formats 0, 1, 1A, 1B, 1C, 1D, 2 , 2A, 2B, 2C DCI, 2D, 3, 3A, 4). This already specified DCI message is then reused for the purpose of carrying the TDD configuration indicator.

In addition, for the case where there are several invalid values available for the invalid parameter (especially for higher bandwidths), it is possible to encode at least one of the above additional parameters into the invalid parameter in the same way as for the first and second. embodiment.

For example, assuming a case where DCI format 1C having the least number of bits is used, the 1C DCI format RBA parameter can be used as an invalid parameter and can be set to an invalid value. As explained in detail for the first embodiment, the RBA parameter may take on a different number of invalid values depending on the bandwidth used in the cell. One invalid value is the same across the entire bandwidth, namely where all bits of the RBA parameter are set to one. For most bandwidths, however, the RBA parameter may have multiple invalid values; 6 PRBs have 2 invalid RBA values; 15 PRBs have 4 invalid RBA values; there are 50 invalid RBA values for 25 PRBs; 50 PRBs have 62 invalid RBAs for slot 1, and 83 invalid RBAs for slot 2; 75 PRBs have 120 invalid RBAs, and 100 and 110 PRBs have 212 invalid RBAs.

Additional information may be encoded into this invalid DCI parameter other than indicating that the DCI carrying the invalid parameter carries the UL / DL TDD configuration indicator. The additional information may be one of the aforementioned other parameters, namely, at least one of TDD configuration, target cell ID, HARQ instruction, action time parameter, BRS instruction, SR instruction, RACH instruction, and PHR instruction. Of course, if one of the mentioned parameters is encoded into an invalid parameter, then the DCI need not contain the said specific parameter separately in its payload.

Therefore, in one modification of the third embodiment (and indeed also of the second embodiment), the 1C DCI format for dynamic TDD reconfiguration includes the RBA parameter set to an invalid value (but encoding the specific TDD configuration) and a padding field for the remaining bits, a field padding set to a predefined value and used as the virtual CRC.

The base station generates the DCI as explained above, and then calculates an error detection code (CRC) for the DCI thus generated. CRC is scrambled by the base station with RNTI; which RNTI is used is not critical to the operation of the third embodiment, however, it is beneficial for the mobile station to limit the operation to only one or limited RNTI value (s) in order to minimize the risk of erroneously detecting a successful DCI transmission due to transmission errors. A useful modification of the third embodiment, where SI-RNTI is used for scrambling, will be explained in detail further below.

The base station transmits the DCI and the scrambled CRC for the DCI, and the mobile station (s) located in the cell receive the DCI and the scrambled CRC. DCI and CRC processing by the mobile station according to the third embodiment will be explained with reference to FIG. 13.

The mobile station listens on the PDCCH and EPDCCH to detect DCI messages destined for the mobile station. Thus, the mobile station receives the DCI and CRC from the base station. The CRC is descrambled and the DCI content is processed.

The mobile station then determines whether the DCI contains an invalid parameter, and if so, the mobile station infers that the DCI is not a normal DCI but is used by the base station for dynamic TDD reconfiguration and thus indicates a specific TDD configuration. The mobile station then proceeds to determine the specific DCI-encoded TDD configuration in one of various ways, as explained above. Namely, the mobile station can either read the actual value of the TDD configuration field as shown in FIG. 10 and associate the value with the corresponding configuration; or the mobile station determines the invalid parameter value and associates the determined invalid parameter value with the corresponding TDD configuration.

In addition, depending on whether the DCI includes additional parameters, the MS may determine the value of any other parameter in the DCI, such as target cell (s), expiration time, HARQ instruction, BRS instruction, SR instruction, RACH instruction, and / or PHR instruction; whether another parameter is encoded into an invalid parameter or present as a separate parameter in the DCI payload.

For example, the mobile station determines, from a specific target cell ID, a specific target cell or group of cells for which the encoded TDD configuration is intended and should be applied. The TDD reconfiguration should be applied by the mobile station only if the mobile station actually belongs to the identified target cell. Otherwise, the TDD reconfiguration may be ignored by the mobile station. Details as to how the information extracted from these additional parameters is used are explained separately below in connection with these parameters.

The TDD configuration thus determined is then applied by the mobile station for a specific time. As in the case of the first embodiment, this can either be preset to be a fixed amount of time, such as 1, 2, or 4 radio frames. Alternatively, the time can be specified dynamically, for example using an action time parameter already mentioned previously as being (optionally) part of the DCI payload or encoded into an invalid parameter (see above). Assuming that the mobile station receives the DCI / CRC transmission in radio frame n, it then processes the DCI and CRC accordingly and applies the indicated TDD configuration for a certain number of radio frames n + 1, n + 2, n + 3, etc., depending on from the action time parameter in DCI or a predefined fixed amount of time. After the dynamically indicated TDD configuration "expires", that is, is no longer applied, the mobile station switches back to the default TDD configuration until, for example, it receives another TDD DCI for dynamic UL / DL TDD reconfiguration.

Alternatively, the mobile station may also transition to applying a new TDD configuration until it accepts another TDD reconfiguration; in other words, the new TDD configuration is not indicated for a specific time value, but indefinitely, unless otherwise specified.

One improved modification of the third embodiment relates to a CRC for DCI scrambled by a base station with RNTI system information (SI-RNTI) and, in addition, the TDD DCI configuration transmitted in the SI receive window, which normally should not be used by the base station to send the system information. information. This will be explained in detail below.

In the prior art, time domain scheduling for MIB and SIB1 messages is fixed at intervals of 40 ms and 80 ms, respectively. Each SI message is transmitted in a predetermined periodically occurring time-domain window, while the physical layer control signaling indicates in which subframes in that window the SI is actually scheduled. The scheduling windows of the various SI messages (referred to as SI windows or SI receive windows) are sequential (ie, there are no overlaps or gaps between them), and have an overall length that is configurable. SI windows may include subframes in which SI messages cannot be transmitted, such as subframes used for SIB1 and subframes used for uplink in TDD.

SI messages can have different periodicities. Therefore, in some clusters of SI windows, all SI messages are scheduled, while in other clusters only SI messages with shorter repetition periods are transmitted. For one example, an SI window cluster starting at System Frame Number (SFN) 0 contains all SI messages, and a cluster starting at another SFN may only contain the first SI message, depending on predefined periodicities. For a more specific discussion of SI windows, please refer to the technical standard or The UMTS Long Term Evolution - From Theory to Practice edited by Stefanie Sesia, Issam Toufik, Matthew Baker, Chapters 3.2.2 and 3.2.2.1, incorporated by reference. ...

As a result, depending on specific periodicities (especially for long periods / repetition cycles), there will be SI windows in which no SI is transmitted, and thus these SI windows will not be used by the base station to transmit system information. This can be used.

In one modification of the third embodiment, the DCI whose CRC is scrambled with the SI-RNTI is transmitted by the base station in one of said unused SI windows. The mobile station knows in advance that this particular SI window will not be used to transmit system information, since the mobile station is also aware of the SI message periods. Thus, when the mobile station receives the SI message (i.e., the DCI TDD whose CRC is scrambled with the SI-RNTI), the mobile station knows that it cannot be a regular SI message. Accordingly, it is aware that this SI message received within the SI window, which normally should not be used by the base station to transmit the SI message, should be a TDD configuration message. In addition, the mobile station can confirm this by determining if the DCI payload includes an invalid parameter.

To free the mobile station from the cost of detecting possible SI messages in SI windows that would not normally be used by a base station to transmit an SI message, a further modification of the third embodiment defines a "TDD-DCI receive window". The TDD-DCI reception window is to be understood as restrictive where the mobile station should expect a TDD-DCI message only for exactly specific subframes and / or radio frames. In other words, a preferably periodic structure of - possibly but not necessarily contiguous - subframes and / or radio frames is defined as a TDD-DCI receive window (or equivalent structure) where a TDD-DCI message can be transmitted by a base station and / or only requires to be received and detection by a mobile station.

Such a window can be used in general with any of the described embodiments and regardless of the SI-RNTI used. For illustrative purposes, the following describes a situation where a TDD-DCI receive window is used and SI-RNTI is used to scramble a CRC for DCI. As mentioned above, the UE may know that the detected DCI is a TDD DCI if the DCI is detected in an SI window that is not used for SI message transmissions as a function of the configured SI periodicities. Such unused SI windows may therefore occur more or less frequently. Therefore, it may be advantageous - in order to create more TDD DCI transmission opportunities - to define the TDD-DCI reception window. In case the subframe is part of the used SI window as well as part of the TDD-DCI receive window, preferably the mobile station associates the successfully detected DCI with the CRC scrambled by the SI-RNTI as being TDD-DCI and not used for the purpose of indicating SI transmission. Alternatively, in such a situation, the mobile station interprets the DCI as TDD-DCI if an invalid parameter is detected in the DCI, and as DCI to indicate SI transmission otherwise.

According to a modification of the third embodiment, the DCI CRC is scrambled by SI-RNTI. In case the mobile station detects this in an unused SI window and / or in a subframe defined as part of the TDD-DCI reception window, the mobile station knows that the DCI is for the TDD configuration message. In this modification, DCI assigns physical resources for transport block transmission in the same manner as, for example, currently DCI format 1A can be used to assign physical resources for a transport block. Said transport block may then submit a MAC or RRC message that contains TDD (re) configuration information and parameters, such as a TDD configuration index or additional parameters outlined in the following sections of this application. Therefore, instead of (or in addition to) the TDD indicator in the DCI message, the transport block indicated by the DCI message contains the TDD indicator.

Extra options

The above first, second and third embodiments mention that additional parameters may be included in the downlink control information used for dynamic UL / DL TDD reconfiguration, either as separate DCI parameters or encoded into an invalid parameter. These parameters have only been briefly described and will be explained in more detail below.

Target Cell ID

As is evident from the term, this identifier should identify the specific cell to which the UL / DL TDD configuration transmitted with DCI / CRC is to be applied. However, this parameter should be some used in DCI and may be different from that used for scrambling CRC in DCI, as explained for the second embodiment. For example, while the SC-RNTI used for scrambling is 16 bits, the target cell ID to be included in the DCI payload may be of any suitable size.

There may be scenarios in which one cell transmits a UL / DL TDD dynamic reconfiguration message, although UL / DL TDD reconfiguration should be applied in another cell. This may be the case for the above extended local zone (eLA) scenario. Specifically, if the TDD configuration is for SCell, then preferably dynamic TDD reconfiguration can be transmitted to PCell.

Depending on the number of different cells in the system, only a few bits are needed for the target cell ID to distinguish between different cells.

The target cell ID can be implemented in various ways. For example, certain 3GPP Release 8 physical cell identification data (PCID, in TS 36.211; PhysCellID in TS 36.331), PCIDs directly pointing to the index may be used. Alternatively, the numbering currently used to add and modify SCell (parameters SCellIndex, sCellToAddModList, SCellToAddMod-r10, see, for example, TS 36.331 document, section 5.3.10.3b and other sections therein) can be used directly, or can a new relationship be established between the target cell ID and the target cell.

Another way to implement the target cell identifier relates to the use of a 3-bit (component) carrier indicator field (CIF). The CIF is usually for cross-carrier scheduling and identifies the carrier to which the scheduling applies. The CIF can thus identify the other carrier, and thus allows the mobile station to determine for which cell (carrier) the TDD configuration received from the DCI should be applied. This preferably reuses numbering and relationships similar to SCell's augment and modification procedure (TS 36.331 document, section 5.3.10.3b and the SCelllndex, sCellToAddModList, SCellToAddMod-r10 parameters described elsewhere in it)

Another optional capability for the target cell identifier is similar to the Coordinated Multipoint (COMP) method of 3GPP Release 10. Instead of indicating a physical cell ID, the target cell ID indicates one or more resources or reference symbol configurations, such as a CRS port or a CSI-RS resource, a resource as defined in TS 36.211, sections 6.10.1 and 6.10.5, and as defined in the information element CSI-RS-Config (PTC CSI configuration) in TS 36.311.

Another optional possibility for the target cell ID is to establish a new relationship between the target cell ID and the target cell.

Accordingly, the mobile station determines the target cell from this target cell ID included in the DCI.

Action time parameter

As explained in the background section, compared with other TDD reconfiguration methods based on, for example, MAC or RRC, TDD reconfiguration using the DCI / CRC of the present invention should be on the order of 10ms. Of course, the TDD dynamic reconfiguration indicator may only be valid for one radio frame; however, this is overhead because the same TDD reconfiguration message would need to be sent every 10ms.

According to another solution, the DCI may include an action time parameter indicating the amount of time that the TDD reconfiguration should be valid. The action time parameter can be implemented in different ways, and can have different length in bits.

The use of a 1-bit action time parameter allows a distinction between the two periods during which the TDD configuration must be valid; for example, 10 ms and 40 ms, that is, 1 radio frame and 4 radio frames. Apparently, one radio frame will be the shortest acceptable valid time for such dynamic UL / DL TDD reconfiguration. 4 radio frames are equivalent in size to the MBSFN interval (single frequency broadcast network with multicast). Of course, any time value other than 10 and 40 ms can be set, such as 100 ms or 200 ms. 200 ms, that is, 20 radio frames, is equivalent to the RRC timeline for TDD reconfiguration. Thus, the gap between the TT reconfiguration timelines using the PHY layer (i.e., DCI / CRC) and the MAC / RRC layer can be bridged without losing the ability to quickly reconfigure.

Using more than 1 bit, that is, 2 bits or more, for the action time parameter naturally allows more flexible TDD reconfiguration.

Thus, the mobile station determines the amount of time to apply the dynamic TDD configuration indicated by said DCI / CRC.

HARQ instruction

The HARQ instruction for causing the mobile station (s) to restart or not restart the HARQ protocol upon applying the new TDD configuration relates to the problem caused by the TDD configuration change, as will be explained in conjunction with FIG. 14.

For purposes of illustration, in FIG. 14, it is assumed that the UL / DL TDD pattern # 3 is applied to radio frame n, and the UL / DL TDD pattern # 5 is applied to the next radio frame n + 1. As depicted, subframes 3, 4 change from uplink transmission to downlink transmission. Accordingly, the number of HARQ processes or the timing for UL HARQ may change when reconfiguring the UL / DL TDD subframes, as can be seen in TS 36.213 section 7 (with Table 7-1), section 8, section 8.3 (with Table 8.3-1) , and section 10, including subsections, specifically subsection 10.2. In case there are fewer HARQ processes, the UE cannot know which process is going on and which earlier PDCCH is the reference for the periodic switching of the New Data Indicator (NDI). Some of the resulting problems will be described in more detail below.

The HARQ procedure for the PDSCH received in subframes 7, 8 and 9 of radio frame n shows ambiguities. The ACK / NACK feedback for the intended PDSCH transmission in these subframes 7, 8 and 9 can no longer be performed correctly, since subframes 3 and 4 from radio frame n + 1 no longer allow PUCCH sending with ACK / NACK feedback.

The HARQ parameter can configure the HARQ behavior in the mobile station to apply UL / DL TDD reconfiguration.

The first optional possibility is that the HARQ instruction mandates a complete restart of the HARQ protocol so that all subsequent transmissions initiate a new transport block. Implicitly, HARQ buffers are flushed, that is, discarded. The advantage is that the destruction of the HARQ buffers can be avoided.

This first optional feature can be indicated by the following procedure. The NDI for all uplink HARQ processes is set to 0. Soft buffers for all downlink HARQ processes are cleared. For each downlink HARQ process, the next received transmission for a transport block is considered the very first transmission.

A second optional capability for the HARQ instruction parameter is that the HARQ protocol does not have a restart. Thus, HARQ buffers are retained to allow the HARQ protocol to continue throughout the UL / DL TDD reconfiguration in order to optimize across the entire bandwidth. This is beneficial if most of the old TDD configuration HARQ processes succeed during TDD reconfiguration.

Therefore, there is a trade-off between the first and second optional capability, and the base station can set the HARQ instruction to one of two values. A 1-bit HARQ instruction field is sufficient in this preferred case.

Therefore, the mobile station determines from this parameter what the behavior is with respect to the HARQ processes.

Fill field

The padding field may be inserted into the DCI with a predetermined value known to the mobile station as well as the base station so that the mobile station can determine whether the padding field accepts a predetermined value. If the DCI contains a padding field with a predetermined value, the mobile station can determine that the received DCI is indeed transporting UL / DL TDD reconfiguration. Therefore, the padding field allows the mobile station to secondarily determine that the DCI is transporting the UL / DL TDD configuration; not only by RNTI TDD (first embodiment), SC-RNTI (second embodiment), or an invalid parameter in DCI (third embodiment).

The padding field is preferably included in DCI in 3GPP Format such as Format 1C to use the remaining DCI bits that may not be used for any of the other parameters. The padding field can thus be 1 to 32 bits long. When using a DCI of a particular size, and after deciding and setting the specific additional parameters to be included in the DCI, there will often be bits remaining that will not otherwise be used. Therefore, to use these bits as well, a padding field is used.

The term "virtual CRC" can also be used by one of ordinary skill in the art to describe such a padding field using specific bit values.

Thus, the mobile station can compare the value of the padding field with a predetermined value to ensure that the DCI carrying said padding field is indeed intended to carry dynamic TDD reconfiguration.

Buffer Status Report (BSR)

BSR instructions from the mobile station to the base station are used to facilitate the allocation of uplink resources. Typically, the more the buffer at a mobile station is full, the more resources or more often resources must be assigned to that mobile station for uplink transmission. Details can be found in The UMTS Long Term Evolution - From Theory to Practice, edited by Stefanie Sesia, Issam Toufik, Matthew Baker, Chapter 4.4.2.2.

BSR reporting is a MAC function that implies that the corresponding transport blocks in the physical layer undergo HARQ with possible retransmissions. BSR can be triggered under several circumstances, including expiration of the 'periodicBSR' timer. Details can be found in The UMTS Long Term Evolution - From Theory to Practice, edited by Stefanie Sesia, Issam Toufik, Matthew Baker, Chapter 4.4.2.2, incorporated by reference.

As mentioned, there may be some ambiguity or confusion between the mobile station and the base station regarding the state of the HARQ protocol regarding the application of TDD reconfiguration. In the case of a BSR transmission, therefore, there may be a misunderstanding if the BSR is part of the (retransmission) uplink transmission after TDD reconfiguration. Therefore, the mobile station may receive a parameter to know if the BSR procedure should be restarted, which may imply one or more of the following:

- canceling or restarting pending (retry) BSR transmissions

- reset / restart timer 'periodicBSR'

- reset / restart of the 'retxBSR' timer

Scheduling Request (SR) and Random Access Channel (RACH) Procedure

In case the mobile station intends to transmit the BSR, but there are no or insufficient uplink resources for transmitting the BSR, the mobile station may transmit the SR to the base station on PUCCH or using the RACH procedure. Details can be found in The UMTS Long Term Evolution - From Theory to Practice, edited by Stefanie Sesia, Issam Toufik, Matthew Baker, Chapter 4.4.2.2, incorporated by reference. Since the timing when the PUCCH can be transmitted for the received PDSCH transmission is usually affected by TDD reconfiguration as shown in FIG. 14, and the RACH procedure may go out of the radio frame, i.e., influenced by TDD reconfiguration due to a change in position and the number of available DL and UL transmission capabilities to complete the entire RACH procedure, it may be safer against errors to inform the mobile station to cancel or restart the SR and / or RACH procedure again after applying the new TDD configuration.

Generation of the power reserve report (PHR)

Like BSR, PHR is used to control uplink transmission power for a mobile station. The base station can use PHR to determine how much more uplink bandwidth per subframe the mobile station is able to use. Details can be found in The UMTS Long Term Evolution - From Theory to Practice, edited by Stefanie Sesia, Issam Toufik, Matthew Baker, Chapter 18.3.3, incorporated by reference.

Since the available uplink transmission power per subframe must be distributed over the entire assigned uplink bandwidth, this is equivalent to reporting the power headroom. A PHR is triggered, for example, when a significant change in the estimated path loss has been detected since the last PHR, or when a configurable time has elapsed since the previous PHR ('PHR inhibit timer'), or when more TPC commands have been issued by the mobile station than set in the configuration.

Like the BSR, the PHR is transmitted as MAC information on the assigned uplink resources, and hence the procedure may be affected by TDD reconfiguration. Therefore, the additional parameter may tell the mobile station to do one or more of the following upon TDD reconfiguration:

- cancel pending PHR report

- initiate a new PHR report

- reset / restart the inhibit timer PHR

- reset the TPC command counter or set it to a given value

Hardware and software implementation of the invention

Another embodiment of the invention relates to the implementation of the above-described various embodiments using hardware and software. In this regard, the invention provides a user equipment (mobile terminal) and an eNodeB (base station). The user equipment is adapted to perform the methods described in the document.

Additionally, it is recognized that various embodiments of the invention may be implemented or executed using computing devices (processors). The computing device or processor may, for example, be general purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), programmable gate arrays (FPGAs), or other programmable logic devices, etc. Various embodiments of the invention can also be performed or implemented by a combination of these devices.

In addition, various implementations of the invention could also be implemented by means of software modules that are executed by a processor, or directly in hardware. In addition, a combination of software modules and hardware implementation is possible. Program modules can be stored on any kind of computer-readable medium, such as random access memory (RAM), erasable programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), flash memory, registers, hard disk drives, CD ROM -disc (CD-ROM), digital multifunction disc (DVD), etc.

It should be further noted that individual features of various embodiments of the invention may, individually or in an arbitrary combination, be the subject of another invention.

One skilled in the art should understand that numerous changes and / or modifications can be made to this invention, as shown in specific embodiments, without departing from the spirit and scope of the invention as outlined. The present embodiments are therefore to be considered in all respects illustrative and non-limiting.

Claims (44)

1. A mobile station for processing one of a plurality of duplex communication configurations, operating in one of a plurality of time division duplex (TDD) configurations in a communication system, the mobile station comprising: a receiver that, in operation, receives a System Information Block (SIB) that includes a default TDD configuration defining uplink, downlink, and special subframes in one or more radio frames, each radio frame including multiple subframes, and receives downlink control information and a corresponding error detection code for downlink control information, wherein the error detection code is scrambled with an identifier associated with the mobile station, a processing circuit connected to the receiver, which, in operation: in response to successfully decoding the downlink control information with the error detection code scrambled by said identifier, determines a TDD configuration from a plurality of TDD configurations including a default TDD configuration based on the downlink control information, defines at least one serving cell to which said specific TDD configuration is to be applied, applies said determined TDD configuration to radio frame n + 1 in said at least one serving cell, where n corresponds to a radio frame in which downlink control information and error detection code are received by the mobile station, and in response to the expiration of said specific TDD configuration, applies the default TDD configuration to radio frame n + 1 + x, where x is a positive integer. 2. The mobile station of claim 1, wherein x is 1, 2, or 4. 3. The mobile station of claim 1, wherein the communication system is an LTE communication system and the downlink control information is 1C downlink control information. 4. The mobile station of claim 1, wherein the downlink control information indicates at least one of the following: a TDD configuration to be applied to said at least one serving cell in the TDD configuration field, a HARQ instruction including an instruction to restart or not restart the HARQ protocol of the mobile station for a serving cell to which said specific TDD configuration is applied upon application of said specific TDD configuration, an action time parameter for said specific TDD configuration, indicating the amount of time during which said specific TDD configuration should be applied, a bit value of a padding field that is or is not the same as a predefined bit value, instructions of the buffer status reporting procedure instructing to cancel the current buffer status reporting procedure or to initiate a new buffer status reporting procedure, upon applying said specific TDD configuration, instructions of a scheduling request procedure instructing to cancel the current scheduling request procedure or initiate a new scheduling request procedure upon applying said specific TDD configuration, a random channel access procedure instruction instructing to cancel the current random channel access procedure or initiate a new random channel access procedure upon applying said specific TDD configuration, and instructions for generating a power headroom report instructing to cancel the current generation of a power headroom report or to initiate a new generation of a power headroom report upon application of said specific TDD configuration. 5. A method for indicating one of a plurality of duplex communication configurations executed by a mobile station operating in one of a plurality of time division duplex (TDD) configurations in a communication system, the method comprising: receive a system information block (SIB), which includes a default TDD configuration defining uplink, downlink and special subframes in one or more radio frames, each radio frame including multiple subframes, receiving downlink control information and a corresponding error detection code for downlink control information, the error detection code being scrambled with an identifier associated with the mobile station, in response to successfully decoding the downlink control information with the error detection code scrambled by said identifier, determining a TDD configuration from a plurality of TDD configurations including a default TDD configuration based on the downlink control information, define at least one serving cell to which said specific TDD configuration is to be applied, applying said determined TDD configuration to radio frame n + 1 in said at least one serving cell, where n corresponds to a radio frame in which downlink control information and error detection code are received by the mobile station, and in response to the expiration of said specific TDD configuration, the default TDD configuration is applied to radio frame n + 1 + x, where x is a positive integer. 6. The method of claim 5, wherein x is 1, 2, or 4. 7. The method of claim 5, wherein the communication system is an LTE communication system and the downlink control information is 1C downlink control information. 8. The method of claim 5, wherein the downlink control information includes an invalid parameter with one of a plurality of invalid values, and one of the plurality of TDD configurations is indicated by one or more of the invalid values, wherein one or more of the invalid values indicate at least one of the following: the specified TDD configuration, HARQ instructions to restart or not restart the mobile station HARQ protocol for the serving cell to which the TDD configuration is applied upon applying said TDD configuration, an expiration time parameter indicating the amount of time during which a specified TDD configuration should be applied, instructions of a buffer status reporting procedure instructing to cancel the current buffer status reporting procedure or initiate a new buffer status reporting procedure upon applying the specified TDD configuration, a scheduling request procedure instruction instructing to cancel the current scheduling request procedure or initiate a new scheduling request procedure upon applying said TDD configuration instructions for a random channel access procedure instructing to cancel the current random channel access procedure or initiate a new random channel access procedure, upon applying said TDD configuration, and instructions for generating a power headroom report instructing to cancel the current generation of a power headroom report or initiate a new generation of a power headroom report upon application of the specified TDD configuration. 9. The method of claim 5, wherein the downlink control information indicates at least one of the following: a TDD configuration to be applied to said at least one serving cell in the TDD configuration field, a HARQ instruction including an instruction to restart or not restart the HARQ protocol of the mobile station for a serving cell to which said specific TDD configuration is applied upon application of said specific TDD configuration, an action time parameter for said specific TDD configuration, indicating the amount of time during which said specific TDD configuration should be applied, a bit value of a padding field that is or is not the same as a predefined bit value, instructions of a buffer status reporting procedure instructing to cancel the current buffer status reporting procedure or to initiate a new buffer status reporting procedure upon applying said specific TDD configuration, instructions of a scheduling request procedure instructing to cancel the current scheduling request procedure or initiate a new scheduling request procedure upon applying said specific TDD configuration, a random channel access procedure instruction instructing to cancel the current random channel access procedure or initiate a new random channel access procedure upon applying said specific TDD configuration, and instructions for generating a power headroom report instructing to cancel the current generation of a power headroom report or to initiate a new generation of a power headroom report upon application of said specific TDD configuration.

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