WO2014161583A1

WO2014161583A1 - Dedicated channel dch enhancements in lte-a: introduction of shared dch

Info

Publication number: WO2014161583A1
Application number: PCT/EP2013/057153
Authority: WO
Inventors: Eric Albert BOUTON; Hans Thomas Hoehne; Karri Markus Ranta-Aho; Antti Anton Toskala
Original assignee: Nokia Solutions And Networks Oy
Priority date: 2013-04-05
Filing date: 2013-04-05
Publication date: 2014-10-09

Abstract

A method comprising: receiving at a user equipment a channel which is shared with a plurality of other user equipment; determining from first information provided by said channel if second information carried by said channel is for said user equipment; and if said determining determines that said second information is for said user equipment, receiving said second information, and if not, causing said user equipment to be in a discontinuous reception mode with respect to said channel.

Description

Title

DEDICATED CHANNEL DCH ENHANCEMENTS IN LTE-A: INTRODUCTION OF SHARED DCH

This disclosure relates to methods, apparatus and computer programs and in particular but not exclusively to methods, apparatus and computer programs for sending and/or receiving information on a channel.

A communication system can be seen as a facility that enables communication sessions between two or more nodes such as fixed or mobile devices, machine-type terminals, access nodes such as base stations, servers and so on. A communication system and compatible communicating entities typically operate in accordance with a given standard or specification which sets out what the various entities associated with the system are permitted to do and how that should be achieved. For example, the standards, specifications and related protocols can define the manner how devices shall communicate, how various aspects of communications shall be implemented and how devices for use in the system shall be configured.

A user can access the communication system by means of an appropriate communication device. A communication device of a user is often referred to as user equipment (UE) or terminal. A communication device is provided with an appropriate signal receiving and transmitting arrangement for enabling communications with other parties. Typically a device such as a user equipment is used for enabling receiving and transmission of communications such as speech and content data. Communications can be carried on wireless carriers. Examples of wireless systems include public land mobile networks (PLMN) such as cellular networks, satellite based communication systems and different wireless local networks, for example wireless local area networks (WLAN). In wireless systems a communication device provides a transceiver station that can communicate with another communication device such as e.g. a base station of an access network and/or another user equipment. The two directions of communications between a base station and communication devices of users have been conventionally referred to as downlink and uplink. Downlink (DL) can be understood as the direction from the base station to the communication device and uplink (UL) the direction from the communication device to the base station.

HSPA (high speed packet access) is a protocol that has been proposed to provide higher performance. It has been proposed to carry voice over HSPA.

According to a first aspect there is provided a method comprising: receiving at a user equipment a channel which is shared with a plurality of other user equipment;

determining from first information provided by said channel if second information carried by said channel is for said user equipment; and if said determining determines that said second information is for said user equipment, receiving said second information, and if not, causing said user equipment to be in a discontinuous reception mode with respect to said channel.

Preferably said channel is a dedicated physical channel. Preferably the method comprises receiving signalling information on said channel.

Preferably said first information is at least one of carried on said channel and provided by said channel. Preferably said first information comprises identification information associated with said user equipment.

Preferably said identification information comprises at least one of: a user equipment transport format combination indication; a user equipment specific cyclic redundancy check; a user equipment specific cyclic redundancy check masked with user equipment identity information; scrambling code specific to said user equipment; recipient-ID.

Preferably said second information comprises a transmission payload. Preferably said second information is received on a second channel.

Preferably mobility information is received on said first channel; and other information is received on said second channel using high speed downlink packet access. Preferably said channel is provided by all base stations in an active set, and said second channel is provided only by a serving high speed downlink packet access base station.

Preferably said user equipment operates with diversity with said first and second base stations.

Preferably said second information comprises signalling information. Preferably said signalling information comprises signalling bearer information.

Preferably the method comprises at least one of receiving data using high speed data packet access, and sending data using high speed packet data access.

Preferably said first and second information are received in a frame.

Preferably said first information is received in a first slot and if said determining determines that said second information is for said user equipment, receiving said second information in at least one of said first slot and at least one other slot of said frame and if not causing said user equipment to be a discontinuous reception mode with respect to said channel for at least one other slot of said frame.

Preferably the method comprises receiving said first information at specified times.

Preferably the method comprises receiving said first information every n frames where n is an integer.

According to a second aspect there is provided a method comprising: providing a channel which is shared by a plurality of user equipment, said channel being divided into a plurality of segments, each segment comprising first information which allows a user equipment to determine if said segment is for that user equipment and second information for the user equipment identified by said first information.

Preferably the method comprises determining if a user equipment is to share said channel in dependence on if said user equipment is in a region of macro diversity. Preferably said plurality of user equipment have a same at least one cell on a list of macro diversity cells. Preferably a plurality of shared channels are provided Preferably said channel is a dedicated physical channel. Preferably the method comprises sending signalling information on said channel

Preferably said first information is at least one of carried on said channel and provided by said channel.

Preferably said first information comprises identification information associated with said user equipment.

Preferably said second information comprises a transmission payload.

Preferably said second information is sent on a second channel.

Preferably mobility information is sent on said first channel; and other information is sent on said second channel using high speed downlink packet access.

Preferably said channel is provided by all base stations in an active set, and said second channel is provided only by a serving high speed downlink packet access base station.

Preferably said user equipment operates with diversity with said first and second base stations. Preferably said second information comprises signalling information.

Preferably said signalling information comprises signalling bearer information. Preferably the method comprises at least one of sending data using high speed data packet access, and receiving data using high speed packet data access.

Preferably said first and second information are provided in a frame. Preferably said first information is provided in a first slot and if said determining determines that said second information is for said user equipment, providing said second information in at least one of said first slot and at least one other slot of said frame and if not causing said user equipment to be a discontinuous reception mode with respect to said channel for at least one other slot of said frame.

Preferably the method comprises sending first information at specified times.

Preferably the method comprises sending said first information every n frames where n is an integer.

According to a third aspect there is provided a computer program comprising computer executable instructions which when run on one or more processors perform the method of the first aspect described above. According to a fourth aspect there is provided a computer program comprising computer executable instructions which when run on one or more processors perform the method of the second aspect as described above.

According to a fifth aspect there is provided an apparatus comprising at least one processor; and at least one memory including computer program code; the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to: receive a channel which is shared with a plurality of other user equipment; determine from first information provided by said channel if second information carried by said channel is for said apparatus; and if said determining determines that said second information is for said apparatus, receiving said second information, and if not, causing said apparatus to be in a discontinuous reception mode with respect to said channel.

Preferably said channel is a dedicated physical channel.

Preferably the apparatus is configured to receive signalling information on said channel.

Preferably said first information comprises identification information associated with said apparatus.

Preferably said identification information comprises at least one of: apparatus transport format combination indication; apparatus specific cyclic redundancy check; apparatus specific cyclic redundancy check masked with apparatus identity information; scrambling code specific to said apparatus; recipient-ID.

Preferably said second information comprises a transmission payload. Preferably said apparatus is configured to receive said second information on a second channel.

Preferably the apparatus is configured to receive mobility information on said first channel; and to receive other information on said second channel using high speed downlink packet access.

Preferably said channel is provided by all base stations in an active set, and said second channel is provided only by a serving high speed downlink packet access base station. Preferably said apparatus operates with diversity with said first and second base stations.

Preferably the apparatus is configured to at least one of receive data using high speed data packet access, and send data using high speed packet data access.

Preferably said apparatus is configured to receive said first and second information in a frame.

Preferably said apparatus is configured to receive said first information in a first slot and if said determining determines that said second information is for said apparatus, the apparatus configured to receive said second information in at least one of said first slot and at least one other slot of said frame, and if not the apparatus configured to enter a discontinuous reception mode with respect to said channel for at least one other slot of said frame.

Preferably the apparatus is configured to receive said first information at specified times.

Preferably the apparatus is configured to receive said first information every n frames where n is an integer.

According to a sixth aspect there is provided an apparatus comprising at least one processor; and at least one memory including computer program code; the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to: provide a channel which is shared by a plurality of user equipment, said channel being divided into a plurality of segments, each segment comprising first information which allows a user equipment to determine if said segment is for that user equipment and second information for the user equipment identified by said first information.

Preferably said apparatus is configured to determine if a user equipment is to share said channel in dependence on if said user equipment is in a region of macro diversity. Preferably said plurality of user equipment have a same at least one cell on a list of macro diversity cells.

Preferably a plurality of shared channels are provided. Preferably said channel is a dedicated physical channel.

Preferably the apparatus is configured to send signalling information on said channel

Preferably said second information comprises a transmission payload.

Preferably said second information is sent on a second channel.

Preferably the apparatus is configured to send mobility information on said first channel; and to send other information on said second channel using high speed downlink packet access.

Preferably the apparatus is configured to at least one of send data using high speed data packet access, and receive data using high speed packet data access.

Preferably said first and second information are provided in a frame.

Preferably the apparatus is configured to provide said first information in a first slot and if said determining determines that said second information is for said user equipment, provide said second information in at least one of said first slot and at least one other slot of said frame, and if not causing said user equipment to be in a discontinuous reception mode with respect to said channel for at least one other slot of said frame. Preferably the apparatus is configured to send first information at specified times.

Preferably the apparatus is configured to send said first information every n frames where n is an integer. According to a seventh aspect there is provided an apparatus comprising means for receiving a channel which is shared with a plurality of other user equipment; means for determining from first information provided by said channel if second information carried by said channel is for said apparatus; and if said determining determines that said second information is for said apparatus, receiving said second information, and if not, causing said apparatus to be in a discontinuous reception mode with respect to said channel.

Preferably said channel is a dedicated physical channel.

Preferably said first information is at least one of carried on said channel and provided by said channel. Preferably said first information comprises identification information associated with said apparatus.

Preferably said second information comprises a transmission payload.

Preferably said apparatus comprises means for receiving said second information on a second channel.

Preferably said apparatus comprises means for receiving mobility information on said first channel; and means for receiving other information on said second channel using high speed downlink packet access.

Preferably said apparatus comprises means for operating with diversity with said first and second base stations.

Preferably said second information comprises signalling information.

Preferably said signalling information comprises signalling bearer information.

Preferably the apparatus comprises means for at least one of receiving data using high speed data packet access, and sending data using high speed packet data access.

Preferably said apparatus is configured to receive said first and second information in a frame. Preferably said apparatus comprises means for receiving said first information in a first slot and if said determining determines that said second information is for said apparatus, the apparatus configured to receive said second information in at least one of said first slot and at least one other slot of said frame, and if not the apparatus comprising means for entering a discontinuous reception mode with respect to said channel for at least one other slot of said frame.

Preferably the apparatus comprises means for receiving said first information at specified times.

Preferably the apparatus comprises means for receiving said first information every n frames where n is an integer.

According to an eighth aspect there is provided an apparatus comprising means for providing a channel which is shared by a plurality of user equipment, said channel being divided into a plurality of segments, each segment comprising first information which allows a user equipment to determine if said segment is for that user equipment and second information for the user equipment identified by said first information. Preferably said apparatus comprises means for determining if a user equipment is to share said channel in dependence on if said user equipment is in a region of macro diversity.

Preferably said plurality of user equipment have a same at least one cell on a list of macro diversity cells.

Preferably a plurality of shared channels are provided.

Preferably said channel is a dedicated physical channel. Preferably the apparatus comprises means for sending signalling information on said channel

Preferably said first information is at least one of carried on said channel and provided by said channel. Preferably said first information comprises identification information associated with said user equipment. Preferably said identification information comprises at least one of: a user equipment transport format combination indication; a user equipment specific cyclic redundancy check; a user equipment specific cyclic redundancy check masked with user equipment identity information; scrambling code specific to said user equipment; recipient-ID. Preferably said second information comprises a transmission payload.

Preferably said apparatus comprises means for sending said second information on a second channel. Preferably said apparatus comprises means for sending mobility information on said first channel; and means for sending other information on said second channel using high speed downlink packet access.

Preferably said user equipment operates with diversity with said first and said second base stations. Preferably said second information comprises signalling information.

Preferably said signalling information comprises signalling bearer information.

Preferably the apparatus comprises means for at least one of sending data using high speed data packet access, and receiving data using high speed packet data access.

Preferably said first and second information are provided in a frame. Preferably the apparatus comprises means for providing said first information in a first slot and if said determining determines that said second information is for said user equipment, providing said second information in at least one of said first slot and at least one other slot of said frame, and if not causing said user equipment to be in a discontinuous reception mode with respect to said channel for at least one other slot of said frame.

Preferably the apparatus comprises means for sending first information at specified times.

Preferably the apparatus comprises means for sending said first information every n frames where n is an integer.

Some embodiments will now be described, by way of example only, with reference to the accompanying figures in which:

Figure 1 shows a schematic diagram of a communication system comprising a base station and a plurality of communication devices;

Figure 2 shows a schematic diagram of a mobile communication device according to some embodiments;

Figure 3 shows a schematic diagram of a control apparatus according to some embodiments;

Figure 4 shows a frame structure for a dedicated physical channel DPCH;

Figure 5 shows a frame structure for a fractional dedicated physical channel F-

DPCH;

Figures 6 shows slot 0 and Figure 7 remaining slots for a downlink DPCH according to some embodiments;

Figure 8 shows timing relationships between DPCHs in a cell;

Figure 9 shows a signalling radio bearer SRB message segmentation embodiment; Figure 10 shows an example of SRB reception on a DPCH as seen by a plurality of UEs in some embodiments;

Figure 11 shows an example of SRB transmission on a DPCH as seen by a base station in some embodiments; and

Figure 12 shows a method of an embodiment.

In the following certain exemplifying embodiments are explained with reference to a wireless or mobile communication system serving mobile communication devices. Before explaining in detail the exemplifying embodiments, certain general principles of a wireless communication system and mobile communication devices are briefly explained with reference to Figures 1 to 3 to assist in understanding the technology underlying the described examples.

In a wireless communication system mobile communication devices or user equipment (UE) 102, 103, 105 are provided wireless access via at least one base station or similar wireless transmitting and/or receiving node or point. In the Figure 1 an example of two overlapping access systems or radio service areas of a cellular system 100 and 1 10 provided by base stations 106 and 107 and three smaller radio service areas 115, 1 17 and 119 provided by remote radio heads or smaller base stations such as pico or femto base stations 1 16, 1 18 and 120 are shown. Each mobile communication device and base station/RRH may have one or more radio channels open at the same time and may send signals to and/or receive signals from more than one source. It is noted that the radio service area borders or edges are schematically shown for illustration purposes only in Figure 1. It shall also be understood that the sizes and shapes of radio service areas may vary considerably from the shapes of Figure 1. A base station site can provide one or more cells. A base station can also provide a plurality of sectors, for example three radio sectors, each sector providing a cell or a subarea of a cell. All sectors within a cell may be served by the same base station.

Base stations are typically controlled by at least one appropriate controller apparatus so as to enable operation thereof and management of mobile communication devices in communication with the base stations. In Figure 1 control apparatus 108 and 109 is shown to control the respective macro level base stations 106 and 107. The control apparatus of a base station can be interconnected with other control entities. The control apparatus is typically provided with memory capacity and at least one data processor. The control apparatus and functions may be distributed between a plurality of control units. In some systems, the control apparatus may additionally or alternatively be provided in a radio network controller.

In Figure 1 base stations 106 and 107 are shown as connected to a wider communications network 1 13 via gateway 112. A further gateway function may be provided to connect to another network.

A possible mobile communication device will now be described in more detail with reference to Figure 2 showing a schematic, partially sectioned view of a communication device 102. Such a communication device is often referred to as user equipment (UE) or terminal. An appropriate mobile communication device may be provided by any device capable of sending and receiving radio signals. Non-limiting examples include a mobile station (MS) or mobile device such as a mobile phone or what is known as a 'smart phone', a computer provided with a wireless interface card or other wireless interface facility, personal data assistant (PDA) provided with wireless communication capabilities, or any combinations of these or the like. A mobile communication device may provide, for example, communication of data for carrying communications such as voice, electronic mail (email), text message, multimedia and so on. Users may thus be offered and provided numerous services via their communication devices. Non-limiting examples of these services include two-way or multi-way calls, data communication or multimedia services or simply an access to a data communications network system, such as the Internet. Users may also be provided broadcast or multicast data. Non-limiting examples of the content include downloads, television and radio programs, videos, advertisements, various alerts and other information.

The mobile device 102 may receive signals over an air interface 207 via appropriate apparatus for receiving and may transmit signals via appropriate apparatus for transmitting radio signals. In Figure 2 transceiver apparatus is designated schematically by block 206. The transceiver apparatus 206 may be provided for example by means of a radio part and associated antenna arrangement. The antenna arrangement may be arranged internally or externally to the mobile device.

A wireless communication device can be provided with a Multiple Input / Multiple Output (MIMO) antenna system. MIMO arrangements as such are known. MIMO systems use multiple antennas at the transmitter and receiver along with advanced digital signal processing to improve link quality and capacity. Although not shown in Figures 1 and 2, multiple antennas can be provided, for example at base stations and mobile stations, and the transceiver apparatus 206 of Figure 2 can provide a plurality of antenna ports. More data can be received and/or sent where there are more antenna elements. A station may comprise an array of multiple antennas. Signalling and muting patterns can be associated with TX antenna numbers or port numbers of MIMO arrangements.

A mobile device is typically provided with at least one data processing entity 201 , at least one memory 202 and other possible components 203 for use in software and hardware aided execution of tasks it is designed to perform, including control of access to and communications with access systems and other communication devices. The data processing, storage and other relevant control apparatus can be provided on an appropriate circuit board and/or in chipsets. This feature is denoted by reference 204. The user may control the operation of the mobile device by means of a suitable user interface such as key pad 205, voice commands, touch sensitive screen or pad, combinations thereof or the like. A display 208, a speaker and a microphone can be also provided. Furthermore, a mobile communication device may comprise appropriate connectors (either wired or wireless) to other devices and/or for connecting external accessories, for example hands-free equipment, thereto.

Figure 3 shows an example of a control apparatus for a communication system, for example to be coupled to and/or for controlling a station of an access system, such as a base station. In some embodiments, base stations comprise a separate control apparatus. In other embodiments, the control apparatus can be another network element such as a radio network controller. In some embodiments, each base station may have such a control apparatus as well as a control apparatus being provided in a radio network controller. The control apparatus 109 can be arranged to provide control on communications in the service area of the system. The control apparatus 109 comprises at least one memory 301 , at least one data processing unit 302, 303 and an input/output interface 304. Via the interface the control apparatus can be coupled to a receiver and a transmitter of the base station. For example the control apparatus 109 can be configured to execute an appropriate software code to provide the control functions.

The communication devices 102, 103, 105 may access the communication system based on various access techniques, such as code division multiple access (CDMA), or wideband CDMA (WCDMA). Other non-limiting examples comprise time division multiple access (TDMA), frequency division multiple access (FDMA) and various schemes thereof such as the interleaved frequency division multiple access (IFDMA), single carrier frequency division multiple access (SC-FDMA) and orthogonal frequency division multiple access (OFDMA), space division multiple access (SDMA) and so on.

An example of wireless communication systems are architectures standardized by the 3rd Generation Partnership Project (3GPP). A latest 3GPP based development is often referred to as the long-term evolution (LTE) of the Universal Mobile Telecommunications System (UMTS) radio-access technology. The various development stages of the 3GPP LTE specifications are referred to as releases. More recent developments of the LTE are often referred to as LTE Advanced (LTE-A). The LTE employs a mobile architecture known as the Evolved Universal Terrestrial Radio Access Network (E-UTRAN). Base stations of such systems are known as evolved or enhanced Node Bs (eNBs) and may provide E- UTRAN features such as user plane Radio Link Control/Medium Access Control/Physical layer protocol (RLC/MAC/PHY) and control plane Radio Resource Control (RRC) protocol terminations towards the communication devices. Other examples of radio access system include those provided by base stations of systems that are based on technologies such as wireless local area network (WLAN) and/or WiMax (Worldwide Interoperability for Microwave Access). Some embodiments may be provided in the context of WCDMA/HSPA.

Macro diversity or soft handover provides higher fault tolerance to connections at for example a cell edge by connecting a user equipment to two different radio cells.

High speed downlink packet access (HSDPA) does not support macro diversity. In order to provide the benefits of macro diversity to fault sensitive signalling connections, the signalling radio bearers (SRBs) in the downlink can be mapped to dedicated channels DCH and user data may be delivered over the high speed downlink shared channel HS-DSCH.

HSDPA works with shared channels. DCH is a dedicated channel. A dedicated channel may dedicate all its resources to one UE event during the times when the UE does not receive data on its HDSPA channels. In other words each DCH uses up a channelization code. This may limit the system's overall capacity. For example with the voice codec AMR (adaptive multi rate) 12.2kbps, this may mean that there are about 124 codes some of which may not be available due to neighbouring cell users being in a soft handover mode.

Continuous packet connectivity CPC is a name for a set of features that help the user equipment to stay on a high-speed channel as long as possible. This is the case even if no data is transmitted and CPC mitigates the negative effects of this, i.e. increased power and/or resource consumption.

For example, the fractional dedicated physical channel (F-DPCH) allows the sharing of the channel by several user equipment by assigning timeslots to different user equipment.

This saves channelization codes and reduces interference because period of discontinuous transmission DTX may be supported.

Currently, CPC can only be enabled with HSDPA and F-DPCH in the downlink and high speed uplink packet access HSUPA in the uplink. This configuration however does not allow macro diversity, not even for SRBs in the down link. Accordingly, currently, having both the macro diversity enabling configuration and the CPC enabling configuration is not possible.

One advantage of DCH enhancements over voice over HSPA is that the downlink soft handover or macro diversity offers better reliability for DCH. There may be lower call drop rates due to mobility because the signalling radio bearer SRB carrying the mobility related control messages benefit from the robustness offered by soft handover or diversity, which is not offered by HSDPA.

One option may be to configure the signalling radio bearer on the DCH in the downlink and deliver user data over the HSDPA. However, this may prevent a CPC benefit from uplink capacity saving and UE battery consumption to be used. In other words, the uplink and downlink DTX and DRX (discontinuous transmission and reception) may not be usable.

Some embodiments may address one or more of a downlink problem of lower cell edge SRB reliability when mapped on HSDPA instead of DCH and/or a problem of allocating a dedicated DCH code in the downlink for each user equipment, reducing the available downlink code channels for HSDPA traffic transmissions. Thus some embodiments configure the SRB in the DL on the DCH while still benefitting at least partially from CPC.

Figure 4 shows a frame structure for a downlink DPCH such as set out in the 3GPP

TS 25.21 1 specification. As can be seen, one radio frame lasts 10ms. The radio frame is divided up into 15 slots, slot 0 to 14. Each slot is 2560 chips, 10^*2^k bits (k =0....7). The slots shown in Figure 4 are divided into DPCCH (dedicated physical control channel) and DPDCH (dedicated physical data channel). Initially, the time slot is allocated to the DPDCH and contains first data, Data 1. Next, the DPCCH is provided which has a TPC (transmit power control part) which has N TPC bits followed by N TFCI (transport format combination indication) bits. This is followed by the DPDCH which comprises a second set of data, Data 2. Finally, this is followed by the DPCCH and contains N pilot bits.

Thus the downlink DCH is mapped on a dedicated DPCH code which consists of time multiplexed data fields Data 1 and Data 2, TPC, TFCI and dedicated pilots such as shown in Figure 4. The TPC bit(s) are used to control the power of the uplink transmission. The TFCI bits are used to inform the user equipment as to the data format used in the data fields.

Reference is made to Figure 5 which shows a frame structure for the F-DPCH. This is as for example shown in 3GPP TS 25.211 specification. This frame structure has the same radio frame length and number of slots as shown and discussed in relation to Figure 4. The each slot has the same length, again as discussed in relation to Figure 4. Each slot has a first part where the transmission is switched off. This is followed by N TPC bits and finally, the transmission is again switched off. While the uplink is transmitting, the downlink provides TPC commands. With CPC, this may be achieved with a time shared F-DPCH code, such as shown in Figure 5.

The downlink SRB may start at any TTI (transmission time interval) boundary. The UE may receive the TFCI bits over 15 slots and when the TFCI indicates that the data fields carry an SRB packet, the user equipment may proceed to decode the received data bits according to the configured TFCS (transmit format combination set) matching the TFCI.

It has been proposed to configure the SRB on the DCH and provide user data on the HSDPA in the downlink direction. However, the SRB on the DCH may consume a dedicated code from the cell code tree for each user equipment reducing the number of codes available for HSDPA data transport. SRB on HSDPA would allow a code saving shared down link power control channel instead of the dedicated one. Configuring a DCH to the radio link may eliminate the uplink capacity benefits and/or user equipment battery savings offered by CPC (DTX and DRX), because CPC is not possible when a DCH is configured.

Some embodiments may configure the SRB on the DCH on the downlink with user data delivered over HSDPA and still obtain at least in part uplink capacity saving and/or user equipment power consumption reductions such as offered by CPC.

A HSPA configuration enabling CPC is provided. In other words HSDPA and F- DPCH are used in the downlink and HSUPA in the uplink. Additionally, at the same time, in the down link, a DPCH code channel is configured to the user equipment. Adding a new shared DCH carrying SRB in the downlink in parallel requires the UE to occasionally check that channel in the downlink, thus leading to some modification of when the UE can enter the DRX state. Therefore the CPC operation, with the exception of downlink DRX, works as if the DCH was not present. The uplink may be power controlled by the TPC symbols on the F-DPCH. The down link F-DPCH power controlled as previously described.

Thus, some embodiments may provide a downlink DCH code channel configured in addition to the HSDPA and F-DPCH channels used in downlink and HSUPA in uplink.

Some embodiments may time multiplex two or more user equipment on a dedicated channel. Any suitable technique may be used to allow the user equipment to identify the downlink transmission intended for it. For example, one or more of the following may be used: user identity information; user equipment specific TFCI; user specific CRC (cyclic redundancy check); timing of the transmission; and a user equipment specific scrambling using for example a scrambling code specific to the UE. As regards the user equipment specific TFCI, there are 1024 TFCI combinations defined in some standards. However, for SRB-only DCH, only a few TFCI combinations may be specified for a user equipment. For example, user equipment may have one or two TFCI combinations which are different from the one or more TFCI combinations for another user equipment.

The CRC may be calculated using the data packet on the DCH and may be masked with a user equipment specific identity. The specific identity may be any suitable identity and may for example be an H-RNTI (HS-DSCH (high speed- downlink shared channel) radio network transaction identifier)

The timing of the transmission may have an additional benefit of reducing the need for the user equipment to check the downlink continuously and thus allow for example for battery savings to be achieved.

In some embodiments, to permit downlink discontinuous reception on the DCH, the SRB transmission may be controlled to take place at predetermined times in some embodiments. These predetermined times may be for example at predetermined frame boundaries. By way of example, a SRB TTI may be provided at a given frame boundary at a given time interval. In some embodiments, the time interval may be every n radio frames where n is an integer.

The time interval may for example be 40 ms. In other embodiments, different times may alternatively be used. In the 40ms scenario, the user equipment would only need to check the TFCI of every fourth radio frame, (assuming each radio frame is 10 ms) to see whether a SRB been transmitted to it or not. The user equipment may keep the DCH receiver off for the rest of the time to save battery power. This may facilitate the timesharing of two or more user equipment on one DCH channel code as previously discussed.

In some embodiments, the node B may power control the DCH based on at least one of channel quality indicator CQI reports, the used F-DPCH transmission power and any other suitable method. The transmission of SRB on DCH does not require, in some embodiments, uplink DPCCH transmission at the same time for power control command delivery. It should be appreciated that the node-B can power control the DPCH in the same manner.

In some embodiments, the allocation of SRBs either to a high-speed shared channel or to dedicated channels is made dynamically. For example this may depend on the location of the user equipment. For example, only SRBs of user equipment in a soft handover region may be allocated to DCHs whereas the SRBs of other user equipment may be allocated to the HSDPA.

In some embodiments, specific types of SRB flows may be allocated to the DCH and other SRB flows may be allocated to the HSDPA to minimise the DCH usage. For example, mobility related signalling may be carried over the DCH and other signalling over the HSDPA.

A distinction may be made on the basis of some parameter of the user equipment, for example the type of service to which the user equipment has subscribed. The target services could be conversational services such as voice and video calls, and best effort data services could map SRB on HSDPA.

Thus, in some embodiments, the user equipment may be configured in the downlink direction with both F-DPCH, for uplink power control, and DPCH. The DPCH may be such that the user equipment does not need to receive that DPCH in every radio frame. The DPCH may be shared with one or more other user equipment. This may allow for CPC benefits in terms of uplink efficiency and/or user equipment power consumption to be achieved whilst at the same time configuring the signalling radio bearer on the downlink on the DCH with better robustness achievable with soft handover.

Some embodiments may thus combine the radio link robustness from downlink SRB on the DCH with the benefits of HSPA radio with CPC.

Some embodiments may provide a method for two more user equipment to share a unique channelization code for control plane transfer when the SRB are configured on the DCH. Some embodiments may provide a DPCH channel format. Some embodiments may provide a slot format

Reference is made to Figures 6 and 7 which illustrates format for a DPCH according to some embodiments. A 10 ms radio frame is divided into 15 slots. It should be appreciated that in different embodiments, the radio frame may be of a different length. It should be appreciated that in alternative embodiments, a different number of slots may be provided. In other embodiments the UE_ID could be less than one slot, or more than one slot.

Figure 6 shows the division of the radio frame in to two parts: one part carrying the user identification and another part carrying the actual payload of SRB transmission. In Figure 6 the first slot is used for the user identification, and the remaining slots re used for data. It should be appreciated however that in other embodiments this slot allocation may differ. In some embodiments, the slots may comprise two types of slots. The first type of slot is shown in Figure 6 and may be the first slot. However, it should be appreciated that in other embodiments, this slot may be located at any other suitable position. Figure 7 shows the second type of slot and some in some embodiments will be used for the remaining slots, i.e. slot numbers 1 to 14. These slots may only transport data bits in some embodiments,

As can be seen from Figure 6, the first slot type, for example slot number 0, will have user identification information, TFCI and data. It should be appreciated that in some embodiments, the TFCI may be omitted. In some embodiments, the data may be omitted. The data part of the slot in some embodiments may only be used if there are remaining bits which can be used to transport data. In some embodiments, the user identification information and the TFCI may be provided by the same piece of information. For example, the user identity and TFCI may be jointly encoded.

In this embodiment, the user equipment may check the first slot to determine if there is a transmission for it. Only if the user equipment detects its own identity will the user equipment need to receive the following timeslots. If the user equipment does not detect its own user identity, it can stop receiving the downlink DPCH until the next time the user equipment identity information is potentially available. Accordingly, the user equipment may check the next slot number 0 of a transmission time interval in which a SRB transmission for a particular user equipment is allowed. In this way, the user equipment may save power.

In some embodiments, a reserved user identity may be present in order to control a group of user equipment to DRX one or more radio frames. In other words, if the user identity field contains particular information, this is interpreted by one or more user equipment to mean that the user equipment is to DRX that radio frame. The information may be global information or specific to a group of UE.

Thus a network node such a base station or radio network controller which need to transmit information to a mobile station will insert the mobile station identification and the TFCI into the first slot which is transmitted to the UE.

Reference is made to Figure 8 which shows timing relations between physical channels in the cell but users sharing a S(shared)-DCH. As voice communications have fixed packet arrival times and SRB TTI's may only be allowed at fixed frame boundaries, the user equipment sharing a single code may be time aligned by choosing matching t_DPCH as shown in Figure 8. At the beginning of every radio frame, all user equipment in the same group, for example the user equipment sharing the same downlink DPCH code will listen to the SRB, read the information and determine if a sent message is for that or those particular user equipment.

Figure 8 is meant as an example of timing relations between physical channels. The system, however, is not tied to this configuration and different t_DPCH may be attributed to UEs with the same S-DCH. In this case, the RNC can intelligently schedule users, ensuring minimal overlapping of UE_ID and SRB information.

If it is determined that the message is intended for that user equipment, then the user equipment will listen for the whole radio frame which will be comprised of the data bits, for example signalling bits. These will be in the slots of Figure 7, for example.

If the user equipment determines that the sent message is not intended for it, the user equipment will go into the DRX mode and thus save battery.

A scheduler in a controller may allocate code time to user equipment according to their specific signalling needs. The controller may be in the base station and/or the RNC or any other suitable node.

In some embodiments, shared DCH SRB groups are formed for user equipment that have the same active set or the same second strongest entries in the active set. Then, the neighbouring cell may form a shared DCH group comprising the same members for soft handover transmission purposes

For example, cell A has user equipment u1 ,..u5, of which u4 and u5 are in soft handover with cell B. Cell B has user equipment u6, u7, u8, and also transmits soft handover signals with cell B scrambling for u4 and u5. Cell A forms a first shared dedicated channel S-DCH #1 for u4 and u5 with cell A scrambling. Cell B also forms a second shared dedicated channel S-DCH #2 for u4 and u5, but on with cell B scrambling code, and can give it the same timing as the S-DCH #1. This is illustrated in Figure 8

For SRB transmissions on the DCH, the existing RLC/MAC structures provide 148- bit transport blocks for L1 processing. If the message to be transmitted is shorter, the radio link control RLC will add dummy bits to fit the fixed packet data unit PDU size, and if the message is longer L2 will split the message between two or more transport blocks

Reference is made to Figure 9 which shows an example of SRB message segmentation. In particular, reference is first made to Figure 9a. A relatively large SRB message 901 is shown (i.e. too large to fit in one PDU). As represented by reference numbers 902 and 903, the SRB message is divided into two RLC packet data units. The second RLC packet data unit 903 contains padding to fill up the packet data unit. As referenced 904, the logical channel ID (that of the DCH) for SRB message is placed into the MAC header. It should be noted that transport channel selection is not necessary as there is only one DCH transport channel. As referenced 905 and 906 respectively, the message is divided into a first transport block TB1 and a second transport block TB2.

As referenced 907, transport channel coding is then applied. As referenced 908, the TTI length can be 10, 20 or 40 ms in some embodiments. This represents one, two or four radio frames. As there are two transport blocks, two radio frames 909 and 910 are required in order to transport the two transport blocks.

Reference is made to Figure 9b which shows a 250 bit SRB message lasting 10 ms.

This SRB message can be packaged into a single RLC PDU 902 with padding. The MAC handling 904 is as described in relation to Figure 9a except that the data can be packaged into a single transport block 905. The transport channel coding 907 is as described in relation to Figure 9a.

In this example, as the data is smaller, the data can be sent in one radio frame 909 with a TTI length of 10 ms.

It should be appreciated that where there are different transport block size options, the setting of the TFCI is in slot 0. In other words, the TFCI will indicate to the UE which transport block size is being used.

Some embodiments may be used with this 148 bit transport structure. However, it should be appreciated that other embodiments may be used with any other transport structure.

Some of the following embodiments are described by way of example only with one TTI of a SRB transmission carrying a 148-bit transport block. After channel coding the transport block, this provides bits which are fed to rate matching functionality. There may be 516 bits which are fed to the rate matching functionality.

The UEs will be configured in the downlink direction with voice user data mapped to HSDPA and SRBs mapped to the S-DCH formats described above. The S-DCH formats described allow the carrying of more data than presently defined formats for DCH carrying SRB. This means that SRB may be delivered much faster, thus improving latency. Previous SRB over DCH has a data rate of 3.2 kbps and the TTI is 40 ms (4^*10ms), i.e. a transport block is split over 4 radio frames of 10ms, the transmission can start once per 40 ms and the transmission duration is 40 ms. Table 1 shows example of latencies for previous (legacy) and new slot formats according to embodiments for a SRB message

It can be appreciated from this table that the SRB can be delivered more quickly in relation to the legacy example. Where a spreading factor of 256 is used the SRB can be delivered in 20ms (2^*10ms), and where a spreading factor of 128 is used the SRB can be delivered in 10ms. This compares with 40ms for the legacy application, as discussed above.

In some embodiments, the controller may allocate more time on the S-DCH for users with a high signalling need (during mobility procedures, for example) such that longer SRB payloads can be delivered more quickly.

Table 2 shows examples for some potential spreading factor and TTI length combinations that may be used for transmitting the MAC PDU media access control packet data unit, that is a transport block (TB). The 148-bit transport block after encoding and rate matching may be fitted to less than 200 bits, but it may be desirable in some situations and embodiments to use around 400 bits to ensure good coding protection. It should be appreciated that any other suitable number of bits may be used in other embodiments.

Some embodiments may use 10 ms TTI for best latency. In some embodiments a spreading factor SF of SF128 and SF256 with a 10 ms TTI may be used. In some situations the SF256 with a 10ms TT1 may suffer from reduced coding protection.

Table2 - Overview of potential DL DPCH spreading factor and TTI length combinations

SF TTI L1 bits/TTI* Comment

128 10 ms 600 All encoded bits can be sent

128 20 ms 1200 Unnecessarily large

256 10 ms 300 Reduced coding protection

256 20 ms 600 All encoded bits can be sent

512 10 ms 150 TB does not fit

512 20 ms 300 Reduced coding protection 512 40 ms 600 All encoded bits can be sent

^*Not al bits will be available for the transmission due to UEJD and potentially the TFCI needing at least some bits

The "L1 " column shows the number of physical layers per TTI, for a given spreading factor and TTI length combination. Some of the bits are used by the UE ID, after which there needs to be a sufficient number of L1 bits to allow for transmitting the 148 bit SRB PDU after channel coding.

Some examples of slot formats of some embodiments are shown in Tables 3 and 4. In some embodiments, both of these formats may be supported and in other embodiments only one of the formats maybe used. It should be appreciated that in other embodiments, different formats may be used.

Table 3 - DL DPCH slot format without TFCI

Slot format 25 may be used for "slot 0" whilst slot format 26 may be used for the other slots.

Table 4 - DL DPCH slot format without TFCI

Slot format 27 may be used for "slot 0" whilst slot format 28 may be used for the other slots. Examples of transport channel parameters for 12.8 kbps SRBs for shared DCH (S- DCH) are shown below in Table 5. Values in bracket show the corresponding values for the 3.4kbps SRBs currently in 3GPP TS34.108 if different.

Table 6 below is an example of where there is only one valid transport format in the complete transport format combination set. According to this example, if it is known that an SRB message is to be received, then it can be determined that it is an SRB message of this one and only valid format. An implication of this is that there may be no need for a specific TFCI field to indicate which TFCS is being sent, as in this example there is only one to choose from. Therefore in the example of Table 5 it could be considered a UE specific TFCI or UE-ID.

In some embodiments, UE-specific TFCIs may also provide the UE_ID. Alternatively or additionally a UE may have two or more UEJDs which also act as TFCIs. This may be advantageous when the number of states in one of the individual fields (UEJD or TFCI) is limited. This may be used where there is only one or a few TFCIs. For example the few TFCIs for a UE may be 2 or 3. Other numbers of TFCIs for a UE, other than 1 , 2 or 3 may be used in other embodiments.

In some embodiments, no TFCI bits may be used on the S-DCH. In legacy procedures the TFCI provides an index into the TFCS, which is the array of possible TFs (transport formats), which dictate the size of the transport channels that are being multiplexed. In some embodiments, there is only one transport channel, and according to the legacy procedure only two TFs (full size, zero size) would be used. The zero size TF however could alternatively or additionally be achieved by the controller choosing a different UE ID for that radio frame or selecting the "reserved UE ID".

Reference is made to Figure 10 which shows an example of four user equipment user 1 , user 2, user 3 and user 4 sharing one DCH. In frame one, first slot, all of the four user equipment will check the user identity information to see if the frame contains any information intended for that user equipment. In the example shown in figure 10, the identity is that of the first user equipment. Accordingly, the first user equipment will monitor the rest of slot 0 and the remainder of the slots of the radio frame, as previously described. User equipment 2, 3 and 4 will determine that the radio frame does not have any information in the DCH of that radio frame for that user equipment. Accordingly, the user equipment 2, 3 and 4 will be in the DRX mode for the rest of the radio frame.

In frame 2, the user identity information indicates that the DCH contains information for the fourth user equipment user 4. Accordingly, the fourth user equipment user 4 would receive the data on the rest of the frame both for the rest of slot 0 and the remaining frames. However, user equipment 1 , 2 and 3, having identified that the DCH does not contain information for those user equipment in that radio frame, will have the discontinuous reception mode for the rest of the frame for the DCH. Reference is made to Figure 1 1 which shows two shared DCH transmitted by a base station. For example, the first shared DCH shows the transmission from the base station for the example shown in Figure 10. In other words, slot 0 of the first radio frame will include the identity of the first user equipment user 1 , followed by TFCI and data for that first user equipment. In the next frame, the user equipment identity will be that of the fourth user equipment user 4 along with TFCI data for that user. Figure 1 1 also shows a second DCH transmitted by the base station. This second DCH may be in respect of a different set of users. In the arrangement shown in Figure 11 , the second DCH has the first frame for a user equipment with the identity UE_ID 1 1 but the next frame is for the user equipment with the ID UEJD 14. It should be appreciated that the transmission of the shared DCH channels may be offset. That is an S-DCH that is transmitted to a group of users may have an offset that is not tied to any other channels. The offset may be used for SHO purposes and is not mandatory for a new allocation.

It should further be appreciated that the UEs sharing the same S-DCH code may have a different time offset, i.e. their TTI boundaries do not overlap. This mode of operation may facilitate soft handover operation with shared codes. Regardless of whether the UEs sharing the same S-DCH code have the same or different time offsets as shown in Figure 11 , the RNC schedules one UE's SRB transmission at any given time on one S-DCH code.

In some embodiments, users may be grouped into the S-DCH according to cell edges. For example users that have the same second SHO link may be in the same S-DCH SRB. This allows that in the other cell a shared DCH group is formed for SHO with the same UEs as members.

In some embodiments the F-DPCH in parallel is arranged to deliver the TPC bits. Alternatively or additionally the TPC bits are multiplexed within the shared DL DPCH carrying the SRBs in a similar fashion to the way that the F-DPCH operates.

For DL power control, in some embodiments, the TPC bits may be generated by the UE based on F-DPCH SIR (signal to interference ratio). The F-DPCH SIR target may be driven by a F-DPCH BER (bit error rate) target. This may be provide by the network and may be outer loop power control. This may leave the PC loop intact, as in legacy systems. This may provide advantages of backward compatibility.

In DL the CPICH (common pilot channel) is transmitted at constant power, while the user equipment specific DCHs are transmitted with user equipment specific power levels, which the UE seeks to keep at a given level with TPC bits that the UE provides as feedback in UL. The DL F-DPCH TPC commands for UL may be scaled with the user equipment specific DL power.

In some embodiments, the controller schedules in DL radio frames with a special TFCI which may serve only the purpose of tuning the OLPC (outer loop power control for a particular UE, e.g. by transmitting only a CRC. That OLPC frame may be addressed to several users. The OLPC frame may alternatively or additionally be sent on an S-DCH different from the S-DCH on which that user equipment is participating. Thus, there may be a common S-DCH serving only the purpose of tuning the OLPC of the S-DCH user equipment. The frame may alternatively or additionally contain dummy data of different power levels for OLPC tuning.

Alternatively or additionally a TFCS that comprises different slot formats may be provided. There may different transport channel coding parameters. One or other of these options may provide different code protection. This may allow the controller to perform some MCS (modulating and coding scheme) link adaptation, as opposed to transmission power adaptation used at the moment for DCH transmission.

Reference is made to Figure 12 which illustrates a method of an embodiment. This method may incorporate any one or more of the features previously described.

In step S1 , a base station will determine a set of user equipment which are to share a DCH. The base station may select the user equipment based on any suitable criteria, such as previously discussed. For example, the user equipment which are located in a soft hand over region and which share some commonality in neighbourhood cell lists may be selected.

In step S2, the DCH is transmitted. This will be as for example previously described. In step S3, a user equipment will receive the DCH.

In step S4, the user equipment will check the DCH to see if that DCH contains user equipment identity information associated with that user equipment.

In step S5, the user equipment will determine if the DCH contains information for that user equipment in the current radio frame.

If so, the next step is step S6 and the user equipment will receive the rest of the information in the frame, for example information in slot 1 to 14.

If not, the next step will be step S7 and the user equipment will go into the DRX mode.

It is noted that whilst embodiments have been described in relation to HSPA, similar principles may be applied to any other communication system or to further developments with LTE. Therefore, although certain embodiments are described above by way of example with reference to certain exemplifying architectures for wireless networks, technologies and standards, embodiments may be applied to any other suitable forms of communication systems than those illustrated and described herein.

The required data processing apparatus and functions of a controller apparatus, a communication device and any other appropriate apparatus may be provided by means of one or more data processors. The described functions at each end may be provided by separate processors or by an integrated processor. The data processors may be of any type suitable to the local technical environment, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs), application specific integrated circuits (ASIC), gate level circuits and processors based on multi core processor architecture, as non-limiting examples. The data processing may be distributed across several data processing modules. A data processor may be provided by means of, for example, at least one chip. Appropriate memory capacity can also be provided in the relevant devices. The memory or memories may be of any type suitable to the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory.

In general, the various embodiments may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects of the invention may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device, although the invention is not limited thereto. While various aspects of the invention may be illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that these blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof. The software may be stored on such physical media as memory chips, or memory blocks implemented within the processor, magnetic media such as hard disk or floppy disks, and optical media such as for example DVD and the data variants thereof, CD.

The foregoing description has provided by way of exemplary and non-limiting examples a full and informative description of the exemplary embodiment of this invention. However, various modifications and adaptations may become apparent to those skilled in the relevant arts in view of the foregoing description, when read in conjunction with the accompanying drawings and the appended claims. However, all such and similar modifications of the teachings of this invention will still fall within the scope of this invention as defined in the appended claims. Indeed there is a further embodiment comprising a combination of one or more of any of the other embodiments previously discussed.

Claims

1. A method comprising:

receiving at a user equipment a channel which is shared with a plurality of other user equipment;

determining from first information provided by said channel if second information carried by said channel is for said user equipment; and

if said determining determines that said second information is for said user equipment, receiving said second information, and if not, causing said user equipment to be in a discontinuous reception mode with respect to said channel.

2. A method as claimed in claim 1 , wherein said channel is a dedicated physical channel.

3. A method as set forth in claim 1 or claim 2, comprising receiving signalling information on said channel.

4. A method as claimed in any preceding claim, wherein said first information comprises identification information associated with said user equipment.

5. A method as claimed in claim 4, wherein said identification information comprises at least one of:

a user equipment transport format combination indication; a user equipment specific cyclic redundancy check; a user equipment specific cyclic redundancy check masked with user equipment identity information; scrambling code specific to said user equipment; recipient-ID.

6. A method as set forth in any preceding claim, wherein said second information comprises a transmission payload.

7. A method as set forth in any preceding claim, wherein said second information is received on a second channel.

8. A method as set forth in claim 7, wherein mobility information is received on said first channel; and other information is received on said second channel using high speed downlink packet access.

9. A method comprising:

providing a channel which is shared by a plurality of user equipment, said channel being divided into a plurality of segments, each segment comprising first information which allows a user equipment to determine if said segment is for that user equipment and second information for the user equipment identified by said first information.

10. A method as claimed in claim 9, comprising determining if a user equipment is to share said channel in dependence on if said user equipment is in a region of macro diversity.

11. A method as claimed in claim 9 or claim 10 wherein said channel is a dedicated physical channel.

12. A method as claimed in any of claims 9 to 11 , comprising sending signalling information on said channel

13. A method as claimed in any of claims 9 to 12, wherein said first information comprises identification information associated with said user equipment.

14. A method as claimed in claim 13, wherein said identification information comprises at least one of:

15. A method as claimed in any of claims 9 to 14, wherein said second information comprises a transmission payload.

16. A method as claimed in any of claims 9 to 15, wherein said second information is sent on a second channel.

17. A method as claimed in claim 16, wherein mobility information is sent on said first channel; and other information is sent on said second channel using high speed downlink packet access.

18. A computer program comprising computer executable instructions which when run on one or more processors perform the method of any of claims 1 to 8.

19. A computer program comprising computer executable instructions which when run on one or more processors perform the method of any of claims 9 to 17.

20. An apparatus comprising

at least one processor;

and at least one memory including computer program code;

the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to:

receive a channel which is shared with a plurality of other user equipment;

determine from first information provided by said channel if second information carried by said channel is for said apparatus; and

if said determining determines that said second information is for said apparatus, receiving said second information, and if not, causing said apparatus to be in a discontinuous reception mode with respect to said channel.

21. An apparatus as claimed in claim 20, wherein said channel is a dedicated physical channel.

22. An apparatus as set forth in claim 20 or claim 21 , wherein the apparatus is configured to receive signalling information on said channel.

23. An apparatus as claimed in any of claims 20 to 22, wherein said first information comprises identification information associated with said apparatus.

24. An apparatus as claimed in claim 23, wherein said identification information comprises at least one of:

apparatus transport format combination indication; apparatus specific cyclic redundancy check; apparatus specific cyclic redundancy check masked with apparatus identity information; scrambling code specific to said apparatus; recipient-ID.

25. An apparatus as set forth in any of claims 20 to 24, wherein said second information comprises a transmission payload.

26. An apparatus as set forth in any of claims 20 to 25, wherein said apparatus is configured to receive said second information on a second channel.

27. An apparatus as set forth in claim 26, wherein the apparatus is configured to receive mobility information on said first channel; and to receive other information on said second channel using high speed downlink packet access.

28. An apparatus comprising:

at least one processor;

and at least one memory including computer program code;

provide a channel which is shared by a plurality of user equipment, said channel being divided into a plurality of segments, each segment comprising first information which allows a user equipment to determine if said segment is for that user equipment and second information for the user equipment identified by said first information.

29. An apparatus as claimed in claim 28, wherein said apparatus is configured to determine if a user equipment is to share said channel in dependence on if said user equipment is in a region of macro diversity.

30. An apparatus as claimed in claim 28 or claim 29 wherein said channel is a dedicated physical channel.

31. An apparatus as claimed in any of claims 28 to 30, wherein the apparatus is configured to send signalling information on said channel

32. An apparatus as claimed in any of claims 28 to 31 , wherein said first information comprises identification information associated with said user equipment.

33. An apparatus as claimed in claim 32, wherein said identification information comprises at least one of:

34. An apparatus as claimed in any of claims 28 to 33, wherein said second information comprises a transmission payload.

35. An apparatus as claimed in any of claims 28 to 34, wherein said second information is sent on a second channel.

36. An apparatus as claimed in claim 35, wherein the apparatus is configured to send mobility information on said first channel; and to send other information on said second channel using high speed downlink packet access.