GB2477537A

GB2477537A - Femto cell access point, communication system and method therefor

Info

Publication number: GB2477537A
Application number: GB1001882A
Authority: GB
Inventors: Yajian Liu; Kimon Nicolaides
Original assignee: IP Access Ltd
Current assignee: IP Access Ltd
Priority date: 2010-02-05
Filing date: 2010-02-05
Publication date: 2011-08-10
Also published as: GB201001882D0; WO2011095407A1

Abstract

A method for configuring a transmission of data over a communication channel to or from a wireless communication unit within a femto cell comprises, at an access point for the femto cell, receiving an indication of at least one communication channel condition (CQI) from the wireless communication unit and configuring a capacity allocation (transport block size) for the transmission of data to or from the wireless communication unit based at least partly on the received indication. If the indicated communication channel condition is below a threshold level, capacity allocation is configured to be large enough to contain at least one data unit (e.g MAC-d PDU). The invention allows data transmission in an HSDPA RAB to continue in the femto cell when channel quality is low without needing to switch to a R99 packet switched RAB or stopping transmission as would be the case for a conventional macrocell scenario.

Description

Title: FEMTO CELL ACCESS POINT, COMMUNICATION SYSTEM AND METHOD THEREFOR

Description

Field of the invention

The field of this invention relates to a femto cell access point, a communication system and a method therefor. The invention is applicable to, but not limited to, a method for configuring transmission of data over a communication channel to or from a wireless communication unit within a femto cell.

Background of the Invention

Wireless communication systems, such as the 3rd Generation (3G) of mobile telephone standards and technology, are well known. An example of such 3G mobile telephone standards and technology is the Universal Mobile Telecommunications System (UMTS), developed by the 3rd Generation Partnership Project (3GPP) (www.3Qpp.orQ). The 3rd generation of wireless communications has generally been developed to support macro-cell mobile phone communications.

Such macro cells utilise high power base stations (NodeBs in 3GPP parlance) to communicate with wireless communication units within a relatively large coverage area. Typically, wireless communication units, or User Equipment (UEs) as they are often referred to in 3G parlance, communicate with a Core Network (CN) of the 3G wireless communication system via a Radio Network Subsystem (RNS). A wireless communication system typically comprises a plurality of radio network subsystems, each radio network subsystem comprising one or more cells to which UEs may attach, and thereby connect to the network. Each macro-cellular RNS further comprises a controller, in a form of a Radio Network Controller (RNC), operably coupled to the one or more Node Bs, via an lub interface.

High Speed Packet Access (HSPA) is a collection of two mobile telephony protocols that extend and improve the performance of Wideband Code Division Multiple Access (WCDMA) networks, such as a UMTS Terrestrial Radio Access Network (UTRAN). HSPA improves the end-user experience by increasing peak data rates to UEs, reducing latency and providing up to five times more system capacity in the downlink communication channel and up to twice as much system capacity in the uplink communication channel, reducing the production cost per bit compared to previous WCDMA protocols, etc. The protocols that make up HSPA comprise the High Speed Downlink Packet Access (HSDPA) protocols and the High Speed Uplink Packet Access (HSUPA) protocols. HSDPA and HSUPA provide increased performance by using improved modulation schemes and by refining the protocols by which UEs and NodeBs communicate. These improvements lead to a better utilization of the existing radio bandwidth provided by WCDMA.

HSDPA has been included in the UMTS specifications since release 5, and uses a transport channel called the High Speed Downlink Shared CHannel (HS-DSCH) to send packets to UEs. This channel is referred to as being high speed' in order to differentiate it from the more general definition of the Downlink Shared CHannel (DSCH) defined in Release 99 (R99') of UMTS.

HSDPA increases peak data rates and capacity in several ways, such as: (i) Shared-channel transmission, whereby radio resources, such as spreading code space and transmission power, are shared between UEs using time multiplexing, which results in a more efficient use of available spreading codes and power resources; (ii) A shorter Transmission Time Interval (TTI), which reduces round-trip time and improves the tracking of fast channel variations; (iii) Adaptive modulation and coding, whereby the modulation scheming and coding is adapted, for example between Quadrature Phase-Shift Keying (QPSK) and Quadrature Amplitude Modulation (16QAM), on a per-UE basis, depending upon signal quality and cell usage, in order to provide for a greater data rate or greater robustness as required; (iv) Fast scheduling, whereby the HS-DSCH is shared between UEs by way of channel-dependent scheduling, which prioritizes users with the most favourable channel conditions; and (v) Fast re-transmission and soft-combining using Hybrid Automatic Repeat-Request (HARQ), which further increase capacity.

To implement some of the features mentioned above, some of the control functions for HSDPA are located within the NodeB, as opposed to the RNC as is the case for traditional WCDMA, in order to achieve faster adjustment to the channel conditions and to reduce latency in communications to or from the RNC. In particular, the NodeB is modified to perform some of the media access control (MAC) functions, with a modified layer which performs the MAC functions for HSDPA and manages the HS-DSCH referred to as a MAC-hs sub-layer.

As part of the fast scheduling and adaptive modulation and coding functions, HSDPA transmissions to a UE are generally further dependent upon the channel conditions for that UE, in terms of the block size used to transmit data to the UE. The better the channel conditions, the bigger the block of data transmitted to the UE and the higher data rate modulation and coding used. For example, a UE performs signal quality measurements on the HS-DSCH channel for the cell supported by the NodeB, and sends a Channel Quality Indicator (CQI) back to the NodeB along with an indication of the capabilities of the UE. The NodeB then uses the received CQI to determine the channel conditions between itself and the UE. The NodeB then bases the transport block size available to the RNC for downloading data to the UE, and the adaptive modulation and coding for downloading data to that UE, on the determined channel conditions and the capabilities of the UE.

The purpose of such HSDPA transport block size adaptation is to avoid unnecessary HARQ re-transmissions by limiting the amount of data transmitted when the channel conditions are poor. If the channel conditions become sufficiently poor (i.e. fall below a desired quality threshold level) the determined transport block size for the UE becomes too small to accommodate a single data unit, for example a single MAC-d PDU (protocol data unit), and so the RNC and NodeB stop transmitting data to the UE over the HS-DSCH channel.

In a conventional UMTS macro cell, R99 coverage (e.g. voice coverage and R99 packet switched coverage) provided over an R99 DCH channel covers approximately the same coverage area as the control pilot channel (CPICH) coverage area. However, HSDPA coverage provided over an HS-DSCH channel is typically much smaller since the power allocated to HSDPA is typically configured to be a small percentage of the total downlink power (e.g. 40% of the total power) in order to ensure sufficient power is available for other types of services. Accordingly, when the HS-DSCH channel conditions drop to a level that is too low for HSDPA transmissions, R99 coverage will typically still be sufficient to maintain a call. In order for an active call being provided over an HS-DSCH channel to be continued when the HS-DSCH channel conditions drop too low for HSDPA transmissions, it is necessary for the RNC, NodeB and UE to reconfigure to an R99 packet switched radio access bearer (RAB), and for the data being transmitted within the call to continue to be transmitted over a slower' R99 DCH channel.

Lower power (and therefore smaller coverage area) femto cells (or pico-cells) are a recent development within the field of wireless cellular communication systems. Femto cells or pico-cells (with the term femto cells being used hereafter to encompass pico-cells or similar) are effectively communication coverage areas supported by low power base stations (otherwise referred to as Access Points (APs)). These femto cells are intended to be able to be piggy-backed onto the more widely used macro-cellular network and support communications to UEs in a restricted, for example in-building', environment.

In this regard, a femto cell that is intended to support communications according to the 3GPP standard will hereinafter be referred to as a 3G femto cell. Similarly, an access controller intended to support communications with a low power base station in a femto cell according to the 3GPP standard will hereinafter be referred to as a 3rd generation access controller (3G AC). Similarly, an Access Point intended to support communications in a femto cell according to the 3GPP standard will hereinafter be referred to as a 3rd Generation Access Point (3G AP).

Typical applications for such 3G APs include, by way of example, residential and commercial (e.g. office) locations, hotspots', etc, whereby an AP can be connected to a core network via, for example, the Internet using a broadband connection or the like. In this manner, femto cells can be provided in a simple, scalable deployment in specific in-building locations where, for example, network congestion at the macro-cell level may be problematic.

In a femto cell scenario, switching from an HSDPA RAB to an R99 packet switched RAB during a call is undesirable for several reasons. For example, when a UE located within a femto cell is participating in a combined R99 circuit switched (e.g. voice) and HSDPA packet switched multi-RAB call, and moves away from the 3G AP supporting the femto cell, such that HS-DSCH channel conditions drop to a level that is too low for HSDPA transmissions, switching from the HSDPA RAB to an R99 packet switched RAB generates a significant amount of signalling overhead. For resource- constrained femto cell devices, such as a 3G AP, such signalling overhead resulting from the re-configuration of the packet switched connection from an HSDPA RAB to an R99 packet switched RAB can potentially impact on the R99 circuit switched call (e.g. it may cause the voice call to be dropped if the re-configuration fails). Furthermore, such signalling overhead is inefficient with respect to the overall service area of a femto cell, and the cost and complexity of implementing/testing such re-configuration is disproportionately high for such cost-sensitive femto cell devices.

Thus, a need exists for an improved method for configuring a transmission of data over a downlink communication channel to a wireless communication unit within a femto cell, and an access point and integrated circuit adapted therefor.

Summary of the invention

Accordingly, the invention seeks to mitigate, alleviate or eliminate one or more of the above mentioned disadvantages singly or in any combination. Aspects of the invention provide an access point, a communication system comprising such an access point, and a method therefore, as described in the appended claims.

According to a first aspect of the invention, there is provided a method for configuring a transmission of data over a communication channel to or from a wireless communication unit within a femto cell. The method comprises, at an access point for the femto cell, receiving an indication of communication channel conditions from the wireless communication unit and configuring a capacity allocation for the transmission of data to or from the wireless communication unit based at least partly on the received indication of communication channel conditions. If one or more of the indicated communication channel condition(s) is/are below a desired quality threshold level, the step of configuring the capacity allocation comprises configuring a capacity allocation large enough to contain at least one data unit.

Thus, in one example embodiment of the invention, by configuring the capacity allocation large enough to contain at least one data unit when one or more of the indicated communication channel conditions is/are below a desired quality threshold level, data may continue to be transmitted over, say, an HS-DSCH channel by an access point. As such, a packet switched call may be sustained towards an edge of the femto cell without a need for switching from, say, an HSDPA RAB to, say, an R99 packet switched RAB or simply stopping the transmission of data, as would be the case for a conventional macro cell scenario.

According to an optional feature of the invention, the method may comprise determining a capacity allocation based at least partly on the received indication of one or more communication channel conditions, comparing the determined capacity allocation to a minimum capacity for containing at least one data unit, and if the determined capacity allocation is less than the minimum capacity allocation for containing at least one data unit, configuring the capacity allocation to be large enough to contain at least one data unit.

According to an optional feature of the invention, the method may comprise comparing the received indication of one or more communication channel conditions from the wireless communication unit to a communication channel condition threshold value, and if the received indication of one or more communication channel conditions from the wireless communication unit is/are less than one or more communication channel condition threshold value(s), configuring the capacity allocation to be large enough to contain at least one data unit.

According to an optional feature of the invention, if the indicated one or more communication channel conditions is/are below a desired quality threshold level, the method may further comprise re-configuring a queue size for data to be transmitted to the wireless communication unit to a reduced queue size.

According to an optional feature of the invention, if the indicated one or more communication channel conditions is/are below a desired quality threshold level, the method may further comprise setting increased RLC (Radio Link Control) parameters.

According to an optional feature of the invention, if the indicated one or more communication channel conditions is/are below a desired quality threshold level, the method may further comprise making available any unused transmit power allocation for the transmission of data over the communication channel to or from the wireless communication unit.

According to an optional feature of the invention, configuring a capacity allocation for the transmission of data to or from the wireless communication unit may comprise configuring a transport block size.

According to an optional feature of the invention, the method may further comprise configuring a capacity allocation for the downloading of data to the wireless communication unit over a downlink communication channel.

According to an optional feature of the invention, the method may further comprise configuring a capacity allocation for the uploading of data to the wireless communication unit over an uplink communication channel.

According to an optional feature of the invention, the femto cell may form part of a Universal Mobile Telecommunications System (UMTS) network, and the communication channel may comprise at least one of a High Speed Downlink Shared Channel (HS-DSCH) and an Enhanced Dedicated Channel (E-DCH).

According to an optional feature of the invention, the method may further comprise signalling the configured capacity allocation to a controller that is operably coupled to the access point.

According to a second aspect of the invention, there is provided an access point for supporting communication in a femto cell of a cellular communication network. The access point comprises transceiver circuitry arranged to enable communication with at least one wireless communication unit located within the femto cell, and a signal processing module arranged to configure a transmission of data over a communication channel to or from a wireless communication unit within a femto cell. The signal processing module is arranged to receive an indication of communication channel conditions from a wireless communication unit within the femto cell, and configure a capacity allocation for the transmission of data to or from the wireless communication unit based at least partly on the received indication of communication channel conditions. If one or more of the indicated communication channel conditions is/are below a desired quality threshold level, the step of configuring the capacity allocation comprises configuring a capacity allocation large enough to contain at least one data unit.

According to a third aspect of the invention, there is provided a communication system comprising an access point for supporting communication in a femto cell of a cellular communication network. The access point comprises transceiver circuitry arranged to enable communication with at least one wireless communication unit located within the femto cell, and a signal processing module arranged to configure a transmission of data over a communication channel to or from a wireless communication unit within a femto cell. The signal processing module is arranged to receive an indication of communication channel conditions from a wireless communication unit within the femto cell, and configure a capacity allocation for the transmission of data to or from the wireless communication unit based at least partly on the received indication of communication channel conditions. If one or more of the indicated communication channel conditions is/are below a desired quality threshold level, the step of configuring the capacity allocation comprises configuring a capacity allocation large enough to contain at least one data unit.

According to a fourth aspect of the invention, there is provided a computer program product comprising program code for configuring a transmission of data over a communication channel to or from a wireless communication unit within a femto cell. The computer program product comprises program code operable for, at an access point for the femto cell, receiving an indication of communication channel conditions from the wireless communication unit and configuring a capacity allocation for the transmission of data to or from the wireless communication unit based at least partly on the received indication of channel conditions. If one or more of the indicated communication channel conditions is/are below a desired quality threshold level, the step of configuring the capacity allocation comprises configuring a capacity allocation large enough to contain at least one data unit.

These and other aspects of the invention will be apparent from, and elucidated with reference to, the embodiments described hereinafter.

Brief Description of the Drawings

Further details, aspects and embodiments of the invention will be described, by way of example only, with reference to the drawings. Elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. Like reference numerals have been included in the respective drawings to ease understanding.

FIG. 1 illustrates an example of part of a cellular communication network.

FIG. 2 illustrates an example of a block diagram of a femto access point.

FIG. 3 illustrates an example of a simplified flowchart of a method for configuring a transmission of data over a downlink communication channel to a wireless communication unit within a femto cell.

FIG. 4 illustrates an alternative example of a simplified flowchart of a method for configuring a transmission of data over a downlink communication channel to a wireless communication unit within a femto cell.

FIG. 5 illustrates a further alternative example of a simplified flowchart of a method for configuring a transmission of data over a downlink communication channel to a wireless communication unit within a femto cell.

FIG. 6 illustrates a still further alternative example of a simplified flowchart of a method for configuring a transmission of data over a downlink communication channel to a wireless communication unit within a femto cell.

FIG. 7 illustrates a typical computing system that may be employed to implement signal processing functionality in embodiments of the invention.

Detailed Description

Examples of the invention will be described in terms of a 3rd generation (3G) access point for supporting a femto cell within a Universal Mobile Telecommunications System (UMTS) cellular communication network. However, it will be appreciated by a skilled artisan that the inventive concept herein described may be embodied in any type of access point for supporting a femto cell (or similar) within a cellular communication network. In a number of applications, the adaptation of an access point in accordance with the examples of the invention effectively performs a method for configuring the transmission of data over a communication channel to a wireless communication unit within a femto cell. In particular, the access point is arranged to receive an indication of communication channel conditions from the wireless communication unit, and configure a capacity allocation for the transmission of data to the wireless communication unit based at least partly on the received indication of communication channel conditions. If the indicated communication channel conditions are below a desired quality threshold level, the step of configuring the capacity allocation comprises configuring a capacity allocation large enough to contain at least one data unit. In this manner, the transmission of data over the communication channel is capable of being continued, even though the communication channel conditions have dropped below a desired quality level.

Referring now to the drawings, and in particular FIG. 1, an example of part of a cellular communication network, adapted in accordance with an embodiment of the invention, is illustrated and indicated generally at 100. In FIG. 1, there is illustrated an example of a communication system in a form of a 3GPP UMTS network 100 that comprises a combination of a macro cell 185 and a plurality of 3G femto cells 150 in accordance with one embodiment of the invention. For the embodiment illustrated in FIG. 1, the radio network sub-system (RNS) 110 comprises two distinct architectures to handle the respective macro cell and femto cell communications.

In the macro cell scenario, the RNS 110 comprises a controller in a form of a Radio Network Controller (RNC) 136 having, inter alia, signal processing logic 138. The RNC 136 is operably coupled to a NodeB 124 for supporting communications within the macro cell 185. The RNC 136 is further operably coupled to a core network element 142, such as a serving general packet radio system (GPRS) support node (SGSN)Imobile switching centre (MSC), as known.

In a femto cell scenario, an RNS 110 comprises a network element, which for the illustrated embodiment is in a form of a 3G Access Point (3G AP) 130, performing a number of functions generally associated with a cellular communication base station, and a controller in a form of a 3G Access controller (3G AC) 140. As will be appreciated by a skilled artisan, a 3G Access Point is a communication element that supports communications within a communication cell, such as a 3G femto cell 150, and as such provides access to a cellular communication network via the 3G femto cell 150. One envisaged application is that a 3G AP 130 may be purchased by a member of the public and installed in their home. The 3G AP 130 may then be connected to a 3G AC 140 over the owner's broadband internet connection 160.

Thus, a 3G AP 130 may be considered as encompassing a scalable, multi-channel, two-way communication device that may be provided within, say, residential and commercial (e.g. office) locations, hotspots' etc, to extend or improve upon network coverage within those locations. Although there are no standard criteria for the functional components of a 3G AP, an example of a typical 3G AP for use within a 3GPP system may comprise some NodeB functionality and some aspects of radio network controller (RNC) 136 functionality. For the illustrated embodiment, the 3G AP 130 further comprises transceiver circuitry 155 arranged to enable communication with one or more wireless communication units located within the general vicinity of the femto communication cell 150, and in particular within the communication cell 150, such as User Equipment (UE) 114, via a wireless interface (Uu).

The 3G Access Controller 140 may be coupled to the core network (CN) 142 via an lu interface, as shown. In this manner, the 3G AP 130 is able to provide voice and data services to a cellular handset, such as UE 114, in a femto cell in contrast to the macro cell, in the same way as a conventional NodeB, but with the deployment simplicity of, for example, a Wireless Local Area Network (WLAN) access point.

In accordance with some embodiments of the present invention, the 3G AP 130 comprises a signal processing module 165 arranged to configure a transmission of data over a communication channel to a wireless communication unit, within the femto cell 150. An example of a downlink communication channel may comprise a packet switched downlink communication channel, such as High Speed Downlink Shared Channel (HS-DSCH) channel in the case of a UMTS implementation.

An example of an uplink communication channel may comprise a packet switched uplink communication channel, such as an Enhanced Dedicated CHannel (E-DCH) channel in the case of a UMTS implementation. In particular, the signal processing module 165 is arranged to receive an indication of one or more channel conditions from a wireless communication unit, such as UE 114, within the femto cell and configure a capacity allocation for the transmission of data to the wireless communication unit based at least partly on the received indication of the one or more communication channel conditions. If the indicated channel conditions are below a desired quality threshold level, the step of configuring the capacity allocation comprises configuring a capacity allocation that is large enough to contain at least one data unit.

In accordance with some example embodiments the indication of one or more channel conditions may encompass any indication from the following group: (i) a Channel Quality Indicator (CQI), for example such as defined in 3GPP TS 25.214; (ii) an indication of power headroom; (iii) a knowledge of current resource grants for the UE; and/or (iv) a Happy Bit' indicator, as defined in 3GPPTM section 9.2.5.3.1 of 25.321 version 6.i.0.

For example, in a case of a conventional macro scenario, the NodeB 124 may be arranged to implement High Speed Downlink Packet Access (HSDPA) for downloading data to a wireless communication unit, such as the UE 118, over a High Speed Downlink Shared Channel (HS-DSCH).

The transport block size used for HSPDA transmissions to the UE 118 is adapted depending on the one or more communication channel conditions between the NodeB and that UE 118. The better the communication channel conditions that are reported by the UE 118, the larger the transport block size configured by the NodeB 124 for data to be downloaded to the UE 118. As previously mentioned, a purpose of such HSDPA transport block size adaptation is to avoid unnecessary HARQ (Hybrid Automatic Repeat-Request) re-transmissions by limiting an amount of data transmitted when the channel conditions are poorer. If the communication channel conditions become sufficiently poor (e.g. fall below a desired quality threshold level) the determined transport block size for the UE becomes too small to accommodate a single data unit, for example a (medium access control layer) MAC-d PDU (protocol data unit). Hence, in the conventional macro cell scenario, the RNC 136 and NodeB 124 stop transmitting data to the UE 118 over the HS-DSCH channel. In a case of a UMTS network, an HSDPA radio access bearer (RAB) may be reconfigured to an R99 (Release 99) packet switched RAB, such that the data is able to continue to be transmitted over a relatively slower' R99 DCH channel.

However, in the femto cell scenario, switching from an HSDPA RAB to an R99 packet switched RAB during a call is undesirable for several reasons. For example, when a UE located within the femto cell 150 is participating in a combined R99 circuit switched (e.g. voice) and HSDPA packet switched multi-RAB call, and moves away from the 3G AP 130 supporting the femto cell 150 such that HS-DSCH channel conditions drop below the desired quality threshold level, switching from the HSDPA RAB to an R99 packet switched RAB generates a significant amount of signalling overhead.

For low-cost femto cell devices, such as a 3G AP 130, such signalling overhead resulting from the reconfiguration of the packet switched connection from an HSDPA RAB to an R99 packet switched RAB can potentially impact on the performance R99 circuit switched call (e.g. it may cause the voice call to be dropped if the reconfiguration fails). Furthermore, such signalling overhead is inefficient with respect to the overall service area of a femto cell, and the cost and complexity of implementing/testing such reconfiguration is disproportionately high for such low-cost femto cell devices.

-10 -Thus, as described in the hereinafter examples, by configuring the capacity allocation large enough to contain at least one data unit when the indicated one or more communication channel conditions is/are below a desired quality threshold level, as opposed to simply stopping the transmission of data, as is the case for the conventional macro cell scenario, data may continue to be transmitted over, say, an HS-DSCH channel by the access controller 140 and the 3G AP 130 even though the one or more communication channel conditions have dropped below a desired quality threshold level. As such, a packet switched call may be sustained towards an edge of the femto cell without the need for switching from, say, an HSDPA RAB to an R99 packet switched RAB.

By effectively forcing the transmission of data using a capacity allocation (e.g. transport block size) that is large enough to contain at least one data unit when the indicated communication channel conditions are below a desired quality threshold level, that would in a conventional macro scenario advocate the use of a smaller transport block size, the chance of errors occurring within the first HARQ transmission is increased. Such an increase in the likelihood of errors occurring fundamentally contrasts to the conventional philosophy of the HSDPA protocols, since although such errors should be recoverable after a few re-transmissions, such re-transmissions lead to longer delays for delivering individual PDUs. However, because of the relatively small geographical coverage of a single femto cell, and the relatively low level of traffic likely to be present as compared with a macro cell, it is contemplated that the delay caused by such re-transmissions may be sufficiently compensated for in a femto cell scenario by the use of, for example, fast retransmissions and short transmission time intervals (TTIs) as implemented within conventional HSDPA transmissions. Furthermore, by effectively forcing the transmission of data using a capacity allocation that is large enough to contain at least one data unit when the indicated communication channel conditions are below a desired quality threshold level, that would in a conventional macro scenario advocate the use of a smaller transport block size, the handover reliability of multi-RAB sessions may be improved. In particular, since an HSDPA RAB may be sustained at a larger distance from the AP than for a conventional macro scenario, RAB handovers have a greater likelihood of succeeding. This is of particular significance due to the increasing use of high functionality communication devices, and the resulting increased use of packet switched RABs.

Accordingly, it is contemplated that for some example embodiments, the signal processing module 165 of the 3G AP may be further arranged to implement one or more of the following, when configuring the transmission of data over the downlink communication channel: (i) Shared-channel transmission, whereby radio resources such as spreading code space and transmission power may be shared between a plurality of UEs using time multiplexing; (ii) A shorter Transmission Time Interval (TTI); (iii) Adaptive modulation and coding, whereby the modulation scheming and coding may be adapted, for example between QPSK (Quadrature Phase-Shift Keying) and 16QAM (Quadrature Amplitude Modulation), on a per-UE basis depending on signal quality and cell usage; (iv) Fast scheduling, whereby the downlink communication channel may be shared between a plurality of UEs by way of channel-dependent scheduling, which prioritizes users with the most favourable channel conditions; and (v) Fast re-transmission and soft-combining (Hybrid Automatic Repeat-Request -HARQ).

In particular, it is contemplated that for some example embodiments the downlink communication channel over which the signal processing module 165 is arranged to configure a transmission of data may comprise an HS-DSCH channel, and the signal processing module 165 may be arranged to configure the download of data in accordance with at least some aspects of the HSDPA protocols.

In accordance with some example embodiments, the desired quality threshold level may be implemented in terms of an indicated communication channel condition below which a transport block size adapted in accordance with a conventional macro scenario for HSDPA transmissions would become too small to accommodate a data unit, such as a MAC-d PDU. For example, upon receipt of a communication channel condition indication, a capacity allocation, for example in a form of a transport block size, may be determined based on a received indication of one or more communication channel conditions, such as in accordance with an HSDPA implementation for a conventional macro scenario. The determined transport block size may then be compared to a minimum required transport block size for containing, say, one data unit (e.g. a MAC-d PDU), and if the determined transport block size is too small to contain a single MAC-d PDU, the transport block size may be reconfigured to be large enough to contain a MAC-d PDU. In this manner, when the indicated one or more communication channel condition drops to a level where the transport block size would otherwise be too small to accommodate a data unit, the transmission block size is maintained at a sufficient size to accommodate at least one data unit.

As will be appreciated, in a conventional macro scenario for HSDPA transmissions, the transport block size is configured according to not only an indicated channel condition, but also on other parameters, such as network operator configured parameters. For example, an initial transport block size (TBS) may be configured based a channel condition indication (e.g. CQI) received from the UE, and on a CQI-to-TBS mapping table, such as defined in 3GPPTM technical specification 25.214.

This initial transport block size may then be rounded down to a size approximately equal to an integer number of PDUs (typically the transport block size is required to comprise a size equal to one of a range of standard block sizes). Additionally, if there are insufficient protocol data units (PDU5) awaiting transmission, the transport block size may be further reduced as necessary. Accordingly, the relationship between indicated communication channel conditions and a transport block size may be configurable on, for example, a per-network, per radio network sub-system and/or a per cell basis.

Furthermore, the relationship between indicated communication channel conditions and transport block size may vary based on, for example, a current channel load, etc. Accordingly, it is contemplated that a desired quality threshold level for a femto cell may fluctuate due to variations in, for example, traffic load for the access point supporting the cell, etc. -12 -Alternatively, it is contemplated that the desired quality threshold level may be implemented in terms of a communication channel condition threshold value. For example, a received indication of one or more communication channel conditions from a wireless communication unit may be compared to a communication channel condition threshold value, and if the received indication of communication channel conditions is less than the communication channel condition threshold value, the capacity allocation (e.g. the transport block size) may then be configured to be large enough to contain at least one data unit. In this manner, when an indicated communication channel condition is below this communication channel condition threshold value, the capacity allocation (e.g. the transport block size) is configured to be large enough to accommodate at least one data unit, irrespective of the capacity allocation that would otherwise have been allocated, for example in a conventional macro scenario.

In a conventional HSDPA implementation, such as may be implemented within a conventional macro scenario, the RNC 136 carries out HSDPA (MAC-hs) flow control by maintaining a queue of data units (MAC-d PDU5) to be transmitted to the UE 118 over an HS-DSCH channel via the Node 124. The NodeB 124 configures the capacity allocation for the transmission of data units based at least partly on received indications of communication channel conditions (e.g. using Channel Quality Indicators -CQI5) from the UE 118, and regularly (up to once every 2msec.) signals to the RNC 136 a configured capacity allocation, for example in terms of a transport block size, for the transmission of data to the UE 118. The RNC 136 accordingly transmits data units held in the queue to the UE 118 via the NodeB 124 at a rate corresponding to the capacity allocation set by the NodeB 124 over the HS-DSCH channel.

Accordingly, for the illustrated example, the 3G access controller 140 may be arranged to maintain a queue of data units, for example MAC-d PDUs, to be transmitted to the UE 118 over an HS-DSCH channel via the 3G AP 130, and the 3G AP 130 may be arranged to regularly signal to the access controller 140 a configured capacity allocation, for example in terms of a transport block size, for the transmission of data to the UE 118. The 3G access controller 140 may then transmit data units held in the queue at a rate corresponding to the capacity allocation set by the 3G AP 130 over the HS-DSCH channel via the 3G AP 130.

In accordance with some example embodiments, it is contemplated that, if the indicated one or more communication channel conditions are below a desired threshold quality level, the signal processing module 165 may be further arranged to configure a queue size for data to be transmitted to the UE 118, for example corresponding to a queue of data units maintained by the access controller 140, to a reduced queue size. In this manner, an overall round-trip time at the RLC (Radio Link Control) may be reduced to compensate for delays resulting from an increase in the number of errors that are likely to occur within the first HARQ transmission.

Furthermore, in accordance with some example embodiments it is contemplated that, if the indicated communication channel conditions is/are below a desired threshold quality level, the signal -13 -processing module 165 may be arranged to set increased RLC parameters. For example, the signal processing module 165 may be arranged to set one or more of: an increased polling timer, an increased number of re-transmissions for each data unit, an increased number of resets before triggering an RLC unrecoverable error, and/or an increased maximum number of resets. In this manner, the RLC parameters may be enlarged when the communication channel conditions are below a desired threshold quality level, for example in order to improve a reliability of the radio link, and to reduce a chance of a radio link failure.

It is still further contemplated that, in accordance with some example embodiments, if the indicated one or more communication channel conditions is/are below a desired threshold quality level, the signal processing module 165 may be further arranged to make available unused transmit power allocation for the transmission of data over the downlink channel to the UE 118. For example, if the access point 130 is not using all of its transmit power allocation for other services, the signal processing module 165 may configure the transceiver circuitry 155 to use UE 118. In this manner, the signal strength of the download channel may be boosted to improve the channel quality for the UE 118. The amount of unused transmit power used to boost the transmit power for the transmission of data being downloaded to the UE 118 (if available) may be proportional to the amount by which the indicated channel conditions are below the desired threshold quality level.

Referring now to FIG. 2, an example of a block diagram of the femto access point 130 is shown in accordance with one example embodiment of the invention. The example access point 130 contains an antenna 202 coupled to the transceiver circuitry 155. More specifically for the illustrated example, the antenna 202 coupled to a duplex filter or antenna switch 204 that provides isolation between receive and transmit chains within the access point 130.

The receiver chain, as known in the art, includes receiver front-end circuitry 206 (effectively providing reception, filtering and intermediate or base-band frequency conversion). The front-end circuitry 206 is serially coupled to the signal processing module 165. An output from the signal processing module 165 is provided to a transmit element of a network connection 210, for example operably coupling the signal processing module 165 to the access controller 140 via, say, the Internet of FIG. 1. The receiver chain also includes received signal strength indicator (RSSI) circuitry 212, which in turn is coupled to a controller 214 that maintains overall control of the transceiver circuitry of the access point 130. The controller 214 may therefore receive bit error rate (BER) or frame error rate (FER) data from recovered information. The controller 214 is also coupled to the receiver front-end circuitry 206 and the signal processing module 165 (generally realised by a digital signal processor (DSP)). The controller 214 is also coupled to a memory device 216 that selectively stores operating regimes, such as decoding/encoding functions, synchronisation patterns, code sequences, RSSI data and the like. In accordance with examples of the invention, the memory device 216 stores computer-readable code thereon for programming the signal processing module 165 to perform a method for configuring the transmission of data over a downlink communication channel to a wireless communication unit within the femto cell 150. Furthermore, a timer 218 is operably coupled to the -14 -controller 214 to control a timing of operations (transmission or reception of time-dependent signals) within the access point 130.

As regards the transmit chain, this essentially includes a receiving element of a network connection 210, coupled in series through transmitter/modulation circuitry 222 and a power amplifier 224 to the antenna 202. The transmitter/ modulation circuitry 222 and the power amplifier 224 are operationally responsive to the controller 214, and as such are used in transmitting data to a wireless communication unit.

The signal processor module 165 in the transmit chain may be implemented as distinct from the processor in the receive chain. Alternatively, a single processor may be used to implement processing of both transmit and receive signals, as shown in FIG. 2. Clearly, the various components within the access point 130 can be realised in discrete or integrated component form, with an ultimate structure therefore being merely an application-specific or design selection.

In accordance with examples of the invention, the signal processing module 165 of the access point 130 is arranged to execute computer-readable code stored within memory device 216 for programming signal processing logic to perform a method for configuring the transmission of data over a downlink channel to a wireless communication unit within a femto cell. The code is operable for receiving an indication of one or more communication channel conditions from the wireless communication unit and configuring a capacity allocation for the downloading of data to the wireless communication unit based at least partly on the received indication of one or more communication channel conditions. If the indicated one or more communication channel conditions are below a desired quality threshold level, the step of configuring the capacity allocation comprises configuring a capacity allocation large enough to contain at least one data unit Referring now to FIG. 3 there is illustrated an example of a simplified flowchart 300 of a method for configuring a transmission of data over a downlink communication channel to a wireless communication unit within a femto cell according to some example embodiments, such as may be implemented by the signal processing module 165 of the access point 130 of FIG. 1.

The method starts at step 310, and moves on to step 320 with a receipt of an indication of one or more communication channel conditions provided by the wireless communication unit. Next, a transport block size is determined based on the received one or more communication channel conditions indication (for example a CQI-based transport block size) at step 330. The determined CQI-based transport block size is then compared to a data unit size at step 340. If the determined CQI based transport block size is too small to accommodate at least one data unit, the method moves on to step 350 where a transport block size for the transmission of data to the wireless communication unit is configured to a size that is capable of accommodating, for example, at least one data unit. The method then moves on to step 360 where the configured block size for the transmission of data to the wireless communication unit is transmitted to a controller, for example the access controller 140 of FIG. 1. The method then ends at step 370.

-15 -Referring back to step 340, if the determined CQI-based transport block size is sufficiently large to accommodate at least one data unit, the method moves on to step 380 where a transport block size for the transmission of data to the wireless communication unit is configured to be substantially equal to the determined CQI-based transport block size. The method then moves on to step 360 where the configured block size for the transmission of data to the wireless communication unit is transmitted to the controller, and the method then ends at step 370.

Referring now to FIG. 4, there is illustrated an alternative example of a simplified flowchart 400 of a method for configuring a transmission of data over a downlink communication channel to a wireless communication unit within a femto cell according to some example embodiments, such as may be implemented by the signal processing module 165 of the access point 130 of FIG. 1.

The method starts at step 410, and moves on to step 420 with a receipt of an indication of one or more communication channel conditions from the wireless communication unit. Next, a transport block size is determined based on, say, the received one or more communication channel conditions indication (for example a CQI-based transport block size) at step 430. The determined CQI-based transport block size is then compared to a data unit size at step 440. If the determined CQI-based transport block size is too small to accommodate at least one data unit, the method moves on to step 450 where a transport block size for the transmission of data to the wireless communication unit is configured to be a size capable of accommodating, for example, at least one data unit. The method then moves on to step 460 where one or more parameter values indicative of poor communication channel conditions are applied to RLC/transport parameters, such as one or more of a queue size for data to be transmitted, a polling timer, a number of re-transmissions for each data unit, a number of resets before triggering an RLC unrecoverable error, and/or a maximum number of resets, etc. The method then moves on to step 470 where the configured block size for the transmission of data to the wireless communication unit and (where appropriate) the updated RLC/transport parameters are transmitted to a controller, for example the access controller 140 of FIG. 1. The method then ends at step 480.

Referring back to step 440, if the determined CQI-based transport block size is sufficiently large to accommodate at least one data unit, the method moves on to step 490 where a transport block size for the transmission of data to the wireless communication unit is configured to substantially equal the determined CQI-based transport block size. The method then moves on to step 470 where the configured block size for the transmission of data to the wireless communication unit is transmitted to the controller, and the method then ends at step 480.

Referring now to FIG. 5, there is illustrated a further alternative example of a simplified flowchart 500 of a method for configuring a transmission of data over a downlink channel to a wireless communication unit within a femto cell, such as may be implemented by the signal processing module of the access point 130 of FIG. 1.

-16 -The method starts at 510, and moves on to step 520 with a receipt of an indication of channel conditions from the wireless communication unit. Next, a transport block size is determined based on a received one or more communication channel condition indication (for example indicative of a CQI-based transport block size) at 530. The determined CQI based transport block size is then compared to a data unit size at 540. If the determined CQI based transport block size is determined as being too small to accommodate at least one data unit, the method moves on to 550 where a transport block size for the transmission of data to the wireless communication unit is configured to a size capable of accommodating at least one data unit. The method then moves on to step 560 where it is determined whether any unused power allocation is available, for example unused transmit power allocation for services other than the downloading of data to UEs. If it is determined that there is unused power available, the method moves on to step 570 where at least some of the unused transmit power allocation from other services is used to increase the transmit power for the transmission of the data being downloaded to the wireless communication unit. The method then moves on to step 580.

However, if it is determined that there is no unused power available at step 560, the method moves straight to step 580. At step 580, the configured block size for the transmission of data to the wireless communication unit is transmitted to a controller, for example the access controller 140 of FIG. 1, and the method ends at step 590.

Referring back to step 540, if the determined CQI based transport block size is sufficiently large to accommodate at least one data unit, the method moves on to step 555, where a transport block size for the transmission of data to the wireless communication unit is configured substantially to equal the determined CQI based transport block size. The method then moves on to step 580 where the configured block size for the transmission of data to the wireless communication unit is transmitted to the controller, and the method then ends at step 590.

Referring now to FIG. 6, there is illustrated a still further alternative example of a simplified flowchart 600 of a method for configuring a transmission of data over a downlink channel to a wireless communication unit within a femto cell, such as may be implemented by the signal processing module of the access point 130 of FIG. 1.

The method starts at 610, and moves on to step 620 with a receipt of an indication of one or more communication channel conditions from the wireless communication unit. Next, at step 630, the at least one communication channel conditions indication is compared with a channel condition threshold value. If the communication channel conditions indication is less than the communication channel condition threshold value, the method moves on to step 640 where a transport block size for the transmission of data to the wireless communication unit is configured to be a size capable of accommodating at least one data unit, for example a single data unit. The method then moves on to step 650 where the configured block size for the transmission of data to the wireless communication unit is transmitted to a controller, for example the access controller 140 of FIG. 1, and the method ends at step 660.

-17 -Referring back to step 630, if the one or more communication channel conditions indication is greater than the communication channel condition threshold value, the method moves on to step 670 where a transport block size is determined based on the received one or more communication channel conditions indication (CQI based transport block size). Next, at step 680, a transport block size for the transmission of data to the wireless communication unit is configured to substantially equal the determined CQI based transport block size. The method then moves on to step 650 where the configured block size for the transmission of data to the wireless communication unit is transmitted to the controller, and the method then ends at step 660.

It will be appreciated that the inventive concept is not limited to the specific implementations illustrated in the drawings, and in particular with respect to the specific methods illustrated in FIG's 3 to 6. For example, it is contemplated that the methods illustrated in FIG's 4 and 5 may be combined to form a method comprising a combination of steps 460, 560 and 570. Furthermore, it is contemplated that the method of FIG. 6 may be modified to comprise steps corresponding to a combination of steps 460, 560 and 570 of the methods of FIG's 4 and 5. Furthermore, a skilled artisan will appreciate that in other applications, alternative functions/circuits/devices and/or other techniques may be used to implement a method for configuring a transmission of data over a downlink communication channel to a wireless communication unit within a femto cell according to embodiments of the present invention.

In some examples, some or all of the steps illustrated in one or more of the aforementioned flowcharts may be implemented in hardware and/or some or all of the steps illustrated in the flowcharts may be implemented in software.

For the examples illustrated in the drawings and described above, the invention has predominantly been described in terms of configuring the transmission of data over a downlink communication channel, such as a High Speed Downlink Shared Channel (HS-DSCH) channel in the case of a UMTS implementation. However, it is contemplated that the inventive concept may equally be applied to the transmission of data over an uplink communication channel, such as an Enhanced Dedicated CHannel (E-DCH) channel in the case of a UMTS implementation.

For example, in a number of applications, the adaptation of an access point in accordance with some examples of the invention may effectively perform a method for configuring the transmission of data over an uplink communication channel from a wireless communication unit within a femto cell.

In particular, the access point may be arranged to receive an indication of communication channel conditions from the wireless communication unit, and configure a capacity allocation for the transmission of data from the wireless communication unit based at least partly on the received indication of communication channel conditions. Such an indication of communication channel conditions may comprise, by way of example only, one or more of: (i) an indication of power headroom; (ii) a knowledge of current resource grants for the UE; and/or (iii) a Happy Bit' indicator.

-18 -If the indicated communication channel conditions are below a desired quality threshold level, the step of configuring the capacity allocation comprises configuring a capacity allocation large enough to contain at least one data unit. In this manner, the transmission of data over the uplink communication channel is capable of being continued, even though the communication channel conditions have dropped below a desired quality level.

Although some aspects of the invention have been described with reference to their applicability to a UMTSTM (Universal Mobile Telecommunication System) cellular communication system and in particular to a UMTSTM Terrestrial Radio Access Network (UTRAN) of a 3rd generation partnership project (3GPPTM) system, it will be appreciated that the invention is not limited to this particular cellular communication system. It is envisaged that the concept described above may be applied to any other cellular communication system in which data may be downloaded to a wireless communication unit.

Referring now to FIG. 7, there is illustrated a typical computing system 700 that may be employed to implement signal processing functionality in embodiments of the invention. Computing systems of this type may be used in access points and wireless communication units. Those skilled in the relevant art will also recognize how to implement the invention using other computer systems or architectures. Computing system 700 may represent, for example, a desktop, laptop or notebook computer, hand-held computing device (PDA, cell phone, palmtop, etc.), mainframe, server, client, or any other type of special or general purpose computing device as may be desirable or appropriate for a given application or environment. Computing system 700 can include one or more processors, such as a processor 704. Processor 704 can be implemented using a general or special-purpose processing engine such as, for example, a microprocessor, microcontroller or other control module. In this example, processor 704 is connected to a bus 702 or other communications med iurri.

Computing system 700 can also include a main memory 708, such as random access memory (RAM) or other dynamic memory, for storing information and instructions to be executed by processor 704. Main memory 708 also may be used for storing temporary variables or other intermediate information during execution of instructions to be executed by processor 704. Computing system 700 may likewise include a read only memory (ROM) or other static storage device coupled to bus 702 for storing static information and instructions for processor 704.

The computing system 700 may also include information storage system 710, which may include, for example, a media drive 712 and a removable storage interface 720. The media drive 712 may include a drive or other mechanism to support fixed or removable storage media, such as a hard disk drive, a floppy disk drive, a magnetic tape drive, an optical disk drive, a compact disc (CD) or digital video drive (DVD) read or write drive (R or RW), or other removable or fixed media drive.

Storage media 718 may include, for example, a hard disk, floppy disk, magnetic tape, optical disk, CD or DVD, or other fixed or removable medium that is read by and written to by media drive 712. As -19 -these examples illustrate, the storage media 718 may include a computer-readable storage medium having particular computer software or data stored therein.

In alternative embodiments, information storage system 710 may include other similar components for allowing computer programs or other instructions or data to be loaded into computing system 700. Such components may include, for example, a removable storage unit 722 and an interface 720, such as a program cartridge and cartridge interface, a removable memory (for example, a flash memory or other removable memory module) and memory slot, and other removable storage units 722 and interfaces 720 that allow software and data to be transferred from the removable storage unit 718 to computing system 700.

Computing system 700 can also include a communications interface 724.

Communications interface 724 can be used to allow software and data to be transferred between computing system 700 and external devices. Examples of communications interface 724 can include a modem, a network interface (such as an Ethernet or other NIC card), a communications port (such as for example, a universal serial bus (USB) port), a PCMCIA slot and card, etc. Software and data transferred via communications interface 724 are in the form of signals which can be electronic, electromagnetic, and optical or other signals capable of being received by communications interface 724. These signals are provided to communications interface 724 via a channel 728. This channel 728 may carry signals and may be implemented using a wireless medium, wire or cable, fiber optics, or other communications medium. Some examples of a communication channel include a phone line, a cellular phone link, a radio frequency (RF) communication link, a network interface, a local or wide area network, and other communications channels.

In this document, the terms computer program product' computer-readable medium' and the like may be used generally to refer to media such as, for example, memory 708, storage device 718, or storage unit 722. These and other forms of computer-readable media may store one or more instructions for use by processor 704, to cause the processor to perform specified operations. Such instructions, generally referred to as computer program code' (which may be grouped in the form of computer programs or other groupings), when executed, enable the computing system 700 to perform functions of embodiments of the present invention. Note that the code may directly cause the processor to perform specified operations, be compiled to do so, and/or be combined with other software, hardware, and/or firmware elements (e.g., libraries for performing standard functions) to do so.

In an embodiment where the elements are implemented using software, the software may be stored in a computer-readable medium and loaded into computing system 700 using, for example, removable storage drive 722, drive 712 or communications interface 724. The control module (in this example, software instructions or computer program code), when executed by the processor 704, causes the processor 704 to perform the functions of the invention as described herein.

It will be appreciated that, for clarity purposes, the above description has described embodiments of the invention with reference to different functional units and processors. However, it will be apparent that any suitable distribution of functionality between different functional units or processors may be used without detracting from the invention. For example, functionality illustrated to be performed by the signal processing module 165 may be performed by a plurality of processors and/or controllers. Hence, references to specific functional units are only to be seen as references to suitable means for providing the described functionality, rather than indicative of a strict logical or physical structure or organization.

Aspects of the invention may be implemented in any suitable form including hardware, software, firmware or any combination of these. The invention may optionally be implemented, at least partly, as computer software running on one or more data processors and/or digital signal processors or configurable module components such as FPGA devices. Thus, the elements and components of an embodiment of the invention may be physically, functionally and logically implemented in any suitable way. Indeed, the functionality may be implemented in a single unit, in a plurality of units or as part of other functional units.

Although the present invention has been described in connection with some embodiments, it is not intended to be limited to the specific form set forth herein. Rather, the scope of the present invention is limited only by the accompanying claims. Additionally, although a feature may appear to be described in connection with particular embodiments, one skilled in the art would recognize that various features of the described embodiments may be combined in accordance with the invention. In the claims, the term comprising' does not exclude the presence of other elements or steps.

Furthermore, although individually listed, a plurality of means, elements or method steps may be implemented by, for example, a single unit or processor. Additionally, although individual features may be included in different claims, these may possibly be advantageously combined, and the inclusion in different claims does not imply that a combination of features is not feasible and/or advantageous. Also, the inclusion of a feature in one category of claims does not imply a limitation to this category, but rather indicates that the feature is equally applicable to other claim categories, as appropriate.

Furthermore, the order of features in the claims does not imply any specific order in which the features must be performed and in particular the order of individual steps in a method claim does not imply that the steps must be performed in this order. Rather, the steps may be performed in any suitable order. In addition, singular references do not exclude a plurality. Thus, references to a', an', first', second', etc. do not preclude a plurality.

Thus, an improved method for configuring a transmission of data over a downlink communication channel to a wireless communication unit, for example within a femto cell and access point adapted therefor have been described, wherein the aforementioned disadvantages with prior art arrangements have been substantially alleviated. -21 -

Claims

Claims 1. A method for configuring a transmission of data over a communication channel to or from a wireless communication unit within a femto cell, the method comprising, at an access point for the femto cell: receiving an indication of at least one communication channel condition from the wireless communication unit; and configuring a capacity allocation for the transmission of data to or from the wireless communication unit based at least partly on the received indication of at least one communication channel condition; wherein, if the indicated at least one communication channel condition is/are below a threshold level, the step of configuring the capacity allocation comprises configuring a capacity allocation large enough to contain at least one data unit.
2. The method of Claim 1 wherein the method further comprises: determining a capacity allocation based at least partly on the received indication of at least one communication channel condition; comparing the determined capacity allocation to a minimum capacity for containing at least one data unit; and if the determined capacity allocation is less than the minimum capacity allocation for containing at least one data unit, configuring the capacity allocation to be large enough to contain at least one data unit.
3. The method of Claim 1 wherein the method comprises: comparing the received indication of at least one communication channel condition from the wireless communication unit to a channel condition threshold value; and if the received indication of at least one communication channel condition from the wireless communication unit is less than the channel condition threshold value, configuring the capacity allocation to be large enough to contain at least one data unit.
4. The method of any preceding Claim wherein, if the indicated at least one communication channel condition is below a desired quality threshold level, the method further comprises configuring a queue size for data to be transmitted to or from the wireless communication unit to a reduced queue size.
5. The method of any preceding Claim wherein, if the indicated at least one communication channel condition is below a desired quality threshold level, the method further comprises setting, at least one increased radio link control (RLC) parameter.

-22 -
6. The method of any preceding Claim wherein, if the indicated at least one communication channel condition is below a desired quality threshold level, the method further comprises making available at least a part of an unused transmit power allocation for the transmission of data over the communication channel to or from the wireless communication unit.
7. The method of any preceding Claim wherein configuring a capacity allocation for the transmission of data to or from the wireless communication unit comprises configuring a transport block size.
8. The method of any preceding Claim wherein the method comprises configuring a capacity allocation for at least one from a group consisting of: a downloading of data to the wireless communication unit over a downlink communication channel; uploading of data from the wireless communication unit over an uplink communication channel.
9. The method of any preceding Claim wherein the femto cell forms part of a Universal Mobile Telecommunications System (UMTS) network, and the communication channel comprises at least one from a group of: a High Speed Downlink Shared Channel (HS-DSCH); an Enhanced Dedicated Channel (E-DCH).
10. The method of any preceding Claim wherein the method further comprises signalling the configured capacity allocation to a controller operably coupled to the access point.
11. An access point for supporting communication in a femto cell of a cellular communication network, the access point comprising transceiver circuitry arranged to enable communication with at least one wireless communication unit located within the femto cell, and a signal processing module arranged to configure a transmission of data over a communication channel to or from a wireless communication unit within a femto cell, the signal processing module being arranged to: receive an indication of at least one communication channel condition from the at least one wireless communication unit within the femto cell; and configure a capacity allocation for the transmission of data to or from the wireless communication unit based at least partly on the received indication of at least one communication channel condition; wherein, if the indicated at least one communication channel condition is below a threshold level, the step of configuring the capacity allocation comprises configuring a capacity allocation large enough to contain at least one data unit.
12. A communication system comprising an access point for supporting communication in a femto of a cellular communication network, the access point comprising transceiver circuitry arranged to enable communication with at least one wireless communication unit located within the femto cell, and a signal processing module arranged to configure a transmission of data over a communication channel to or from a wireless communication unit within a femto cell, the signal processing module being arranged to: receive an indication of at least one communication channel condition from a wireless communication unit within the femto cell; and configure a capacity allocation for the transmission of data to or from the wireless communication unit based at least partly on the received indication of at least one communication channel condition; wherein, if the indicated at least one communication channel condition is below a threshold level, the step of configuring the capacity allocation comprises configuring a capacity allocation large enough to contain at least one data unit.
13. A computer-readable storage element having computer-readable code stored thereon for programming signal processing logic to perform a method for configuring a transmission of data over a communication channel to or from a wireless communication unit within a femto cell, the code operable for, at an access point for the femto cell: receiving an indication of at least one communication channel condition from the wireless communication unit; and configuring a capacity allocation for the transmission of data to or from the wireless communication unit based at least partly on the received indication of at least one communication channel condition; wherein, if the indicated at least one communication channel condition is below a threshold level, the step of configuring the capacity allocation comprises configuring a capacity allocation large enough to contain at least one data unit.
14. The computer-readable storage element of Claim 13 wherein the computer readable storage element comprises at least one of: a hard disk, a CD-ROM, an optical storage device, a magnetic storage device, a Read Only Memory, ROM, a Programmable Read Only Memory, PROM, an Erasable Programmable Read Only Memory, EPROM, an Electrically Erasable Programmable Read Only Memory, EEPROM, and a Flash memory.
15. An integrated circuit for an access point for supporting communication in a femto cell of a cellular communication network, the access point comprising transceiver circuitry arranged to enable communication with at least one wireless communication unit located within the femto cell, and a signal processing module arranged to configure a transmission of data over a downlink communication channel to a wireless communication unit within a femto cell, the signal processing -24 -module being arranged to: receive an indication of at least one communication channel condition from the at least one wireless communication unit within the femto cell; and configure a capacity allocation for the downloading of data to the wireless communication unit based at least partly on the received indication of at least one communication channel condition; wherein, if the indicated at least one communication channel condition is below a threshold level, the step of configuring the capacity allocation comprises configuring a capacity allocation large enough to contain at least one data unit.