TECHNICAL FIELD:

[0001] The exemplary and non-limiting embodiments of this invention relate generally to wireless communication systems, methods, devices and computer programs; and more specifically relate to determining search space for a user equipment to find a control channel, such as the ePDCCH in the LTE system.

BACKGROUND:

[0002] In Releases 8-10 of the Long Term Evolution (LTE) system, the downlink control information (DCI) is transmitted on the physical downlink control channel (PDCCH) which gives the user equipment (UE) its uplink (UL) and downlink (DL) radio resource allocations/assignments for data. The PDCCH is transmitted on the same set of antenna ports as the physical broadcast channel (PBCH), and so the eNB's antenna port configuration for sending the PDCCH is cell-specific and static. Specifically, the PDCCH transmission mode is either single-antenna port transmission or transmit diversity, depending on the number of antenna ports configured at the eNB. Mapping of logical antenna ports to physical transmit antennas is standard transparent and implementation specific. The radio channel frequency response for the UE's demodulation of the PDCCH is estimated from the common reference signals (CRSs) associated to the eNB's antenna ports.

[0003] In LTE Release 10 (and earlier), the UE does several blind attempts to decode the PDCCH with different assumptions about the coding rate, resource mapping and length of the DCI format. To avoid excessive UE decoding complexity, the concepts of control channel elements (CCEs), CCE aggregation tree and PDCCH search space were introduced. The resource element (RE) space for PDCCHs has been divided into CCEs, and in Release 8 are 36 REs per each CCE. The UE attempts to decode a number of DCI formats of pre-defined size from either 1 , 2, 4 or 8 aggregated CCEs. In other words, when attempting to decode the PDCCH the UE assumes that each DCI fonnat of pre-defined size is mapped to {1, 2,4,8 }x36 REs, which essentially implies the coding rate used for the transmission. This number of CCEs {1,2,4,8} is called the aggregation level. For each aggregation level there are multiple locations from which the UE searches for the DCI format. All locations that the UE will need to search through is called the PDCCH search space.

[0004] LTE Release- 11 has an ongoing work item to add a new scheduling channel ePDCCH, which is to be mapped to the PDSCH region of the subframe and also is to support UE-specific reference signals (UE-RS). The ePDCCH is intended at least to support an increased control channel capacity, to support frequency-domain inter-cell interference coordination (ICIC), to achieve improved spatial reuse of control channel resources, and to support beamforming and/or diversity. To date, the 3 GPP have agreed that the ePDCCH will support both localized and distributed transmission (see Final Report WG1#67). The localized transmission helps to exploit frequency selective scheduling gain and beamforming gain while the distributed transmission may provide robust ePDCCH transmission via frequency diversity in case valid channel state information (CSI) is not available. A rule for resource allocation of the ePDCCH is also agreed, namely "At least for UE-specific search space, a RE that collides with any other signal is not used for ePDCCH". (see document Rl -121978, SEARCH SPACE DESIGN FOR E-PDCCH TRANSMISSION SCHEME, by NTT DOCOMO). Still to be discussed are details concerning resource mapping of the enhanced resource element group (eREG) and the enhanced control channel element (eCCE), multiplexing of the localized ePDCCH and the distributed ePDCCH, and how the UE's search space is to be determined. [0005] One difference between the ePDCCH and the PDCCH is that the demodulation of the ePDCCH will be based on UE-specific reference signals rather than CRSs. The term UE-specific RS does not necessarily mean unique to each UE in the cell; in principle the eNB can configure multiple UEs with the same reference signal (RS) and so any given UE-specific RS could be shared by multiple UEs. The CRSs used for the PDCCH are not precoded whereas the UE-specific RSs used for the ePDCCH are, and the underlying precoding decisions have an effect on the antenna port that is used for the transmission of the ePDCCH to a given UE. For example, the eNB may make one type of precoding/scheduling decision when it uses multi-user multiple-input multiple-output (MU-MIMO) and another for single-user (SU-) MIMO. Therefore the antenna port configuration of the ePDCCH transmission cannot be static as it is in Release 10, in order to preserve precoding/scheduling flexibility at the eNB. In addition to blind decoding of the coding rate, resource and DCI size which the UE needs to do for the PDCCH, for the ePDCCH the UE may need to also use blind decoding attempts in order to find the correct antenna port from among multiple possible UE-specific RS ports that the eNB used for transmitting the ePDCCH to a given UE. This inevitably increases the complexity of channel estimation and hence the complexity of blind detection. To avoid a significant blind decoding complexity increase, the 3 GPP has agreed to the following for antenna port association to the ePDCCH (see Draft Report WG1#69 v020):

^■ In localized allocation, each eCCE index is associated by specification with one antenna port.

^■ In case a DCI message uses multiple eCCEs in the PRB pair, one antenna port (AP) per physical resource block (PRB) pair is selected among the associated APs and used for ePDCCH demodulation.

• It is for further study whether the selection is according to the cell radio network temporary identifier (C-RNTI) or another

UE-specific configuration based rule.

^■ The working assumption that the association from eCCE index of different DCIs to AP is a one-to-one mapping for normal cyclic prefix (CP).

· A many-to-one mapping can be considered further.

Consider both normal and extended CP.

It is for further study for the case of only 2 ports being configured in the system.

^■ In distributed allocation, at least if spatial diversity is used, each eREG/RE index is associated by specification with one antenna port.

^■ The associated AP for each used eREG/RE is used for ePDCCH demodulation. ^■ If it is agreed that the size of a group of REs for the spatial diversity scheme is larger than an eREG, then it is for further study whether the antenna port can be the same for multiple eREGs within a PRB pair. [0006] It was agreed that the eCCE/eREG/RE index is associated with the antenna port, which helps to reduce the blind detection of the ePDCCH. But what is still needed is a way to limit the UE's blind decoding burden for the ePDCCH without limiting the eNB's flexibility in choosing precoders and/or antenna port configurations to transmit the ePDCCH, and particularly how the UE is to detennine the antenna port especially when considering there is the possibility that the eNB can configure multiple PRB pair sets.

SUMMARY;

[0007] In a first exemplary aspect of the invention there is a method comprising: storing in a local memory of a device a predefined mapping of antenna ports to radio resources, wherein the radio resources comprise at least one of resource elements, resource element groups and control channel elements; selecting an antenna port configuration for a user equipment from among multiple predefined antenna port configurations, wherein each of the multiple predefined antenna port configurations consists of two different antenna ports; identifying each of the radio resources which map from at least one antenna port of the selected configuration according to the predefined mapping; defining a search space consisting of the identified radio resources in each physical resource block pair set that is assigned to the user equipment; and either a) transmitting a control channel to the user equipment within the defined search space using the antenna ports of the selected antenna port configuration, or b) confining a blind search for a control channel to the defined search space and the antenna ports of the selected antenna port configuration. [0008] In a second exemplary aspect of the invention there is an apparatus comprising at least one processor and at least one memory storing a computer program. In this aspect the at least one memory with the computer program is configured with the at least one processor to cause the apparatus to at least: store in the at least one memory a predefined mapping of antenna ports to radio resources, wherein the radio resources comprise at least one of resource elements, resource element groups and control channel elements; select an antenna port configuration for a user equipment from among multiple predefined antenna port configurations, wherein each of the multiple predefined antenna port configurations consists of two different antenna ports; identify each of the radio resources which map from at least one antenna port of the selected configuration according to the predefined mapping; define a search space consisting of the identified radio resources in each physical resource block pair set that is assigned to the user equipment; and either a) transmit a control channel to the user equipment within the defined search space using the antenna ports of the selected antenna port configuration, or b) confine a blind search for a control channel to the defined search space and the antenna ports of the selected antenna port configuration

[0009] In a third exemplary aspect of the invention there is a computer readable memory tangibly storing a computer program executable by at least one processor, the computer program comprising: code for storing in a local memory of a device a predefined mapping of antenna ports to radio resources, wherein the radio resources comprise at least one of resource elements, resource element groups and control channel elements; code for selecting an antenna port configuration for a user equipment from among multiple predefined antenna port configurations, wherein each of the multiple predefined antenna port configurations consists of two different antenna ports; code for identifying each of the radio resources which map from at least one antenna port of the selected configuration according to the predefined mapping; code for defining a search space consisting of the identified radio resources in each physical resource block pair set that is assigned to the user equipment; and either a) code for transinitting a control channel to the user equipment within the defined search space using the antenna ports of the selected antenna port configuration or b) code for confining a blind search for a control channel to the defined search space and the antenna ports of the selected antenna port configuration.

[0010] These and other embodiments and aspects are detailed below with particularity. BRIEF DESCRIPTION OF THE DRAWINGS:

[001 1] Figure 1 is a schematic diagram showing resource element groups of different PRB pair sets showing mapping of resource element groups/control channel elements from antenna port, according to an exemplary embodiment of these teachings.

[0012] Figure 2 is similar to Figure 1 but showing mapping from different antenna ports according to another exemplary embodiment of these teachings. [0013] Figure 3 is a logic flow diagram that illustrates from the perspective of the network/eNB and of the UE the operation of a method, and a result of execution of computer program instructions embodied on a computer readable memory, in accordance with an exemplary embodiment of this invention. [0014] Figure 4 is a simplified block diagram of a UE and an eNB which are exemplary electronic devices suitable for use in practicing the exemplary embodiments of the invention.

DETAILED DESCRIPTION:

[0015] The following examples are in the specific context of the LTE/LTE-Advanced systems (for example, Release 1 1 and later) but these teachings are more broadly applicable to any wireless radio system which employs radio resource grants from the network to the UEs where the network has a choice in the antenna port configuration and the reference signal used for transmitting that grant. These examples consider only a single UE but it will be understood the description applies for all such UEs being scheduled for radio resources according to the teachings described for one UE.

[0016] Below are described examples for determining the antenna port configuration used for a control channel transmission which provides a general solution for flexible PRB pair set configuration and localized ePDCCH and distributed ePDCCH multiplexing configurations. This is related to the search space determination for the ePDCCH, and the examples below prove the underlying concept enables quite flexible configurations for localizes ePDCCH and distributed ePDCCH multiplexing, and for single or multiple PRB pair sets configuration, to enable a balance between resource consumption, blocking rate and performance.

[0017] Recall from the background section that both localized and distributed transmission of the enhanced control channel are to be supported. The smallest resource reservation for the ePDCCH is anticipated to be a set of 4 PRB pairs since that provide sufficient frequency diversity for distributed allocations. However, if one PRB pair set is reserved for both localized ePDCCH and distributed ePDCCH respectively, and each set consists of four PRB pairs to provide diversity gain, then it means eight PRB pairs are needed at least. Such overhead is not practical in some cases, especially for narrow bandwidth systems and for the case of a very low number of UEs in the system. Moreover, for distributed ePDCCH each eCCE is distributed to multiple PRB pairs in the PRB pair set. Then once one eCCE is scheduled there, the whole PRB pair set is unusable for PDSCH and this results in a reduction of resource efficiency.

[0018] From this point of view then, multiplexing of localized ePDCCH and distributed ePDCCH in same PRB pair set is desired and it improves the resource efficiency when there is only a small number of UEs present under the coverage area of the transmission point, for example in scenarios with low power nodes each serving only a small geographical area. In such a case the eNB may multiplex the ePDCCH for both UEs monitoring distributed candidates only and also UEs monitoring also localized candidates in the same PRB pairs to save resources.

[0019] But to enable efficient multiplexing of localized ePDCCH and distributed ePDCCH in same PRB pair set, a wise search space design is needed to avoid resource overlapping between localized ePDCCH and distributed ePDCCH, and at the same time avoid a significant increase in signaling and also in implementation complexity. The examples below enable such multiplexing. At the same time the solution enables configuring either 1 or 2 PRB pair sets to the UE. These examples show an efficient way of utilizing all the blind decoding attempts that the UE needs in order for the UE to find its ePDCCH, including when only 1 PRB pair set is configured to the UE.

[0020] Even if a UE only needs to monitor distributed ePDCCH, occasions may arise where that UE could be configured with two PRB pair sets (each having four PRB pairs) instead of only one PRB pair set. One motivation is improved resource utilization since the eNB can utilize one of the PRB pair sets as a primary set, and only schedule ePDCCH to the other set for the case in which the primary set is blocked. Whether one PRB pair set or two PRB pair sets are to be monitored is configurable by the eNB, and the search space design according to these teachings can guarantee a similar blind detection complexity for each configuration, where the blind detection complexity is determined by the number of required channel estimation and the number of ePDCCH candidates.

[0021] Determining the antenna ports for channel estimation and for demodulation of the ePDCCH according to the examples below enables unchanged detection complexity for flexible PRB pair set(s) configurations. As noted above, it has been agreed in 3GPP that there will be a one-to-one mapping between the used antenna ports and the corresponding resources used for transmitting the ePDCCH, so once the antenna port is determined then the search space in terms of resources used for the ePDCCH candidates can be known.

[0022] Following is an overview of the principles of these teachings applied specifically for LTE and the ePDCCH.

• The UE is assigned two APs for ePDCCH demodulation.

· The two APs as a combination is selected from four predefined patterns, for example (AP107, AP109), (API 08, API 10), (API 09, API 07), and (API 10, API 08).

• One predefined pattern can be selected based on its C-RNTI (or on some other UE identifier unique in the cell and known to both the eNB and the UE), so for example if [C-RNTI mod 4]=i, then the two APs in the (i+1 ) ^th pattern are the ones selected. • When the UE is assigned two PRB pair sets, the first AP in the selected pattern is applied in the first set and the second AP is applied in the second set for ePDCCH demodulation.

• The search space is determined based on the selected AP pattern.

[0023] The following examples apply the above principles RE/eREG/eCCE to the above example antenna port configurations for various CCE aggregation levels.

[0024] In a first example explained with reference to Figure 1 the UE is configured with 2 PRB pair sets, and both PRB pair sets are configured for distributed ePDCCH detection. Note that the two PRB pair sets can be configured different or the same. From the eNB's perspective only one PRB pair set could be used by configuring both PRB pair sets the same so they fully overlap. Then the UE will be searching more from the same PRBs but the total number of channel estimations and blind decoding attempts is the same. This is possible because in another embodiment of these teachings the search space in the two PRB pairs will be non-overlapping, so that when the eNB configures the PRB pairs in the two sets to be the same the result is that the UE will make more blind decoding attempts per PRB pair. [0025] Assume that based on UE identifier the selected antenna port pattern is (AP 107, AP 109). AP 107 will be applied to the first PRB pair set while AP 109 will be applied to the second PRB pair set. Now that the antenna ports are determined, then the eNB or UE check the predefined mapping of eREG/eCCE to antenna port to find the candidate eREGs/eCCEs. The Figure 1 and 2 examples of course use a specific predefined mapping but any other mapping which efficiently utilizes the eREGs/eCCEs can be substituted. This predefined mapping in the Figure 1 example is shown in the table below for API 07 and API 09, and partially for the other antenna ports. This mapping will be stored in the local memories of both the eNB (to find the search space in which it must send the ePDCCH) and the UE (to find the candidate eREGs/eCCEs which define the search space where it will blind detect the ePDCCH). [0026]

Table 1. Exam le of eCCE-AP association.

[0027] The search space from the above predefined mapping from antenna configuration (API 07, 109) for the UE configured with two PRB pair sets for distributed ePDCCH is shown at Figure 1. Assume each PRB pair consists 16 eREGs, each small block in Figure 1 represents one eREG, 4 eREGs with the same color/shading forms one eCCE for aggregation level (AL in the table above and Figure and for AL={2, 4, 8} there are {2, 4, 8} eCCEs with the same color/shading that form one ePDCCH candidate. In this first example an equal number of ePDCCH candidates are detected from each PRB pair set based on the AP allocation.

[0028] For AL= 1 the eREGs/eCCEs from table 1 above that are associated with AP 107 will map to PRB pair set #1, and those eREGs are shown in Figure 1 for the first PRB pair set by bolded outlining. The eREGs/eCCEs from table 1 above that are associated with API 09 will map to PRB pair set #2, those eREGs shown in Figure 1 by the same shading as those mapped from API 07 and also bolded outlining, and lie in a same column 3 eREGs below those mapped from API 07 but in the PRB pair set #2. From table 1 above it is clear there are a total of 8 candidate resources in the UE's search space for AL=1 , four each mapped from AP 107 and AP 109.

[0029] For AL=2 the eREGs/eCCEs from table 1 above that are associated with AP107 will map to PRB pair set #1, and are shown in Figure 1 for the first PRB pair set by bolded outlining. The eREGs/eCCEs from table 1 above that are associated with API 09 will map to PRB pair set #2, and occupy the two eREGs below those mapped from API 07 in a same column but in the PRB pair set #2 (also shown by bolded outlining). From table 1 above it is clear there are also a total of 8 candidate resources in the UE's search space for AL=2, four each mapped from API 07 and API 09. [0030] For AL=4 the eREGs/eCCEs from table 1 above that are associated with AP 109 will map to PRB pair set #2, and are shown in Figure 1 for the second PRB pair set by the bolded outline. The eREGs/eCCEs from table 1 above that are associated with API 07 will map to PRB pair set #1, and occupy the block of four eREGs above those mapped from AP 109 in a same pair of columns but in the PRB pair set #1 which is also shown by bolded outlining. From table 1 above it is clear there are a total of 4 candidate resources in the UE's search space for AL=2, two each mapped from API 07 and API 09. [0031] For AL=8 the eREGs/eCCEs from table 1 above that are associated with API 09 will map to PRB pair set #2, and are shown in Figure 1 for the second PRB pair set by the bolded outline. The eREGs/eCCEs from table 1 above that are associated with API 07 will map to PRB pair set #1, and occupy the block of eight eREGs above those mapped from API 09 but in the PRB pair set #1 (shown by bolded outlining). From table 1 above it is clear there are a total of 2 candidate resources in the UE's search space for AL=2, one candidate each mapped from API 07 and API 09.

[0032] In a special case mentioned above, if the configured two sets are the same then both API 07 and API 09 are used for demodulation in the same PRB pair set and this enables the same number of candidates as in the two PRB pair sets case. So for example using AL=1 at Figure 1 for this special case, if the UE were configured with only the PRB pair set #1 then all of the bolded resources indicated in Figure 1 for AL^l would be within that PRB set #1 (and there would be no search space in the PRB pair #2 since it would not be configured to the UE). This flexibility in the PRB pair set configuration is another advantage the techniques herein offer for better efficiency in scheduling radio resources.

[0033] In a second example explained with reference to Figure 2 the UE is configured with 2 PRB pair sets, one PRB pair set being configured for distributed ePDCCH detection and the other for localized ePDCCH detection. But still there is the flexibility for the eNB to configure the two PRB pair sets different or the same, and still from the eNB's perspective only one PRB pair set could be used by configuring both PRB pair sets the same. With the same PRB pairs the eNB can achieve distributed and localized ePDCCH in the same PRB pair.

[0034] For this second example assume that based on UE identity (for example the C-RNTI) the antenna port configuration (API 10, API 08) is selected. Then based on the APs in the selected AP configuration, and using some predefined eREG/eCCE to AP mapping which for this example is again taken from table 1 above, the UE can determine the search space as follows. [0035] The resources mapped from API 10 are the distributed resources so those will be mapped to the first PRB pair set in Figure 2 as shown by the resources offset with bolded outline for AL=1, for AL=4, and for AL=2. The localized resources are mapped from API 08 and lie on the PRB pair set #2 in Figure 2, and these search space candidates are also shown by the bolded outline for AL=1, AL=2 and AL=4.

[0036] From this second example it is seen that the solution presented herein can guarantee the same number of candidates independently of whether 1 or 2 PRB pair sets are used. Additionally it enables localized and distributed multiplexing in the same PRB pair set without resource collision. For this the eNB could configure the UE with only one PRB pair set similar to the special case noted above (technically the eNB configures the UE with two PRB pair sets but the two are the same), in which case the bolded candidate resources for any given AL which are shown at Figure 2 as being mapped to two different PRB pair sets would be all mapped to only the single PRB pair set that the eNB configured for the UE.

[0037] At least some of the embodiments of these teachings for the antenna port association have a configuration of the ePDCCH resources. Specifically, localized and distributed allocations can be multiplexed in the same PRB pair, there is an efficient utilization of antenna ports and of the UE's blind decoding budget when only one PRB pair set is used for ePDCCH, and additionally there is still efficient utilization of 2 PRB pair sets. [0038] Now are detailed with reference to Figure 3 further particular exemplary embodiments from the perspective of both the network/eNB and of the UE. Figure 3 may be performed by the whole eNB or whole UE, or by one or several components thereof such as a modem, a processor in combination with a program stored on a memory, etc. At block 302 a device stores in its local memory a predefined mapping of antenna ports to radio resources such as that shown by example at table 1 above. The radio resources can be at least one of resource elements, resource element groups and control channel elements (including e-versions of any of these; eREs, eREGs, eCCEs). Then at block 304 the device selects an antenna port configuration for a user equipment from among multiple predefined antenna port configurations. In the example above the C-RNTI was used for this purpose. Block 306 reviews that each of the radio resources are identified which map from at least one antenna port of the selected configuration according to the predefined mapping, and then a search space is defined consisting of the identified radio resources in each physical resource block pair set that is assigned to the user equipment.

[0039] From there Figure 3 divides into a eNB branch and a UE branch. At block 308A the eNB transmits a control channel to the user equipment within the defined search space using the antenna ports of the selected antenna port configuration. Or from the UE's perspective at block 308B the UE confines a blind search for a control channel to the defined search space and the antenna ports of the selected antenna port configuration.

[0040] In the examples above each of the multiple predefined antenna port configurations consists of two different antenna ports, which is shown at block 304 in parentheses.

[0041] Also above it was detailed that where the UE is assigned only one physical resource block pair set (for example, assigned the same pair set twice) and the identified radio resources map from both antenna ports of the selected configuration according to the predefined mapping. But where the UE is assigned two physical resource block pair sets: • a first portion of the identified radio resources map from one of the two antenna ports of the selected configuration according to the predefined mapping; and

• a second portion of the identified radio resources map from another of the two antenna ports of the selected configuration according to the predefined mapping.

[0042] Also it was detailed above that the antenna port configuration for the user equipment is selected using at least an identifier of the user equipment; and in the specific example above where N was 4, if there are a total of N predefined antenna port configurations then the antenna port configuration for the UE is selecting utilizing a module N function on the identifier of the user equipment (N is an integer greater than two). It may prove advantageous that the antenna port configuration for a given UE is not fixed for the entire time the UE is in the cell, and so in another embodiment the antenna port configuration for any given UE can be selected as a function of both the UE identifier and time.

[0043] The logic flow diagrams of Figure 3 may each be considered to illustrate the operation of a method, and a result of execution of a computer program stored in a computer readable memory, and a specific manner in which components of an electronic device are configured to cause that electronic device to operate. The various blocks shown in Figure 3 may also be considered as a plurality of coupled logic circuit elements constructed to carry out the associated function(s), or specific result of strings of computer program code stored in a memory. [0044] Such blocks and the functions they represent are non-limiting examples, and may be practiced in various components such as integrated circuit chips and modules, and that the exemplary embodiments of this invention may be realized in an apparatus that is embodied as an integrated circuit. The integrated circuit, or circuits, may comprise circuitry (as well as possibly firaiware) for embodying at least one or more of a data processor or data processors, a digital signal processor or processors, baseband circuitry and radio frequency circuitry that are configurable so as to operate in accordance with the exemplary embodiments of this invention. [0045] Reference is now made to Figure 4 for illustrating a simplified block diagram of various electronic devices and apparatus that are suitable for use in practicing the exemplary embodiments of this invention. In Figure 4 an eNB 22 is adapted for communication over a wireless link 21 with a mobile radio apparatus termed genetically as a UE 20. The eNB 22 may be any access node (including frequency selective repeaters) of any type of radio access technology network such as LTE, LTE-A, WCDMA, and the like. The operator network of which the eNB 22 is a part may also include a network control element such as a mobility management entity MME and/or serving gateway SGW 24 which provides connectivity with further networks (e.g., a publicly switched telephone network and/or a data communications network/Internet) .

[0046] The UE 20 includes processing means such as at least one data processor (DP) 20A, storing means such as at least one computer-readable memory (MEM) 20B which tangibly stores at least one computer program (PROG) 20C or other set of executable instructions, and communicating means such as a transmitter TX 20D and a receiver RX 20E for bidirectional wireless communications with the eNB 22 via one or more antennas 20F. Also stored in the MEM 20B at reference number 20G are the predetennined mapping of the APs of the AP configuration to the REGs and/or CCEs as detailed above in multiple but non-limiting embodiments.

[0047] The eNB 22 also includes processing means such as at least one data processor (DP) 22A, storing means such as at least one computer-readable memory (MEM) 22B that tangibly stores at least one computer program (PROG) 22C or other set of executable instructions, and communicating means such as a transmitter TX 22D and a receiver RX 22E for bidirectional wireless communications with the UE 20 via one or more antennas 22F. The eNB 22 stores at block 22G similar predetennined mapping of the APs of the AP configuration to the REGs and/or CCEs as detailed above in multiple but non-limiting embodiments.

[0048] For completeness, the MME 24 is also shown to have a processor DP 24A, a memory 24B storing a program 24C and a modem 24H for digitally modulating and demodulating information it communicates over the data and control link 25 with the eNB 22. [0049] While not particularly illustrated for the UE 20 or eNB 22, those devices are also assumed to include as part of their wireless communicating means a modem and/or a chipset which may or may not be inbuilt onto an RF front end chip within those devices 20, 22 that may also carry the TX 20D/22D and the RX 20E/22E. [0050] At least one of the PROGs 20C in the UE 20 is assumed to include a set of program instructions that, when executed by the associated DP 20A, enable the device to operate in accordance with the exemplary embodiments of this invention, as detailed above for Figure 4. The eNB 22 also has software stored in its MEM 22B to implement aspects of these teachings relevant to it as detailed above for Figure 3. In these regards the exemplary embodiments of this invention may be implemented at least in part by computer software stored on the MEM 20B, 22B which is executable by the DP 20 A of the UE 20 and/or by the DP 22 A of the eNB 22, or by hardware, or by a combination of tangibly stored software and hardware (and tangibly stored firmware). Electronic devices implementing these aspects of the invention need not be the entire devices as depicted at Figure 5 or may be one or more components of same such as the above described tangibly stored software, hardware, firmware and DP, or a system on a chip SOC or an application specific integrated circuit ASIC.

[0051] In general, the various embodiments of the UE 20 can include, but are not limited to personal portable digital devices having wireless communication capabilities, including but not limited to cellular telephones, navigation devices, laptop/palmtop/tablet computers, digital cameras and music devices, and Internet appliances, as well as the machine-to -machine type devices mentioned above. [0052] Various embodiments of the computer readable MEMs 20B, 22B include any data storage technology type which is suitable to the local technical environment, including but not limited to semiconductor based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory, removable memory, disc memory, flash memory, DRAM, SRAM, EEPROM and the like. Various embodiments of the DPs 20A, 22A include but are not limited to general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and multi-core processors.

[0053] Various modifications and adaptations to the foregoing exemplary embodiments of this invention may become apparent to those skilled in the relevant arts in view of the foregoing description. While the exemplary embodiments have been described above in the context of the LTE and LTE-A system, as noted above the exemplary embodiments of this invention may be used with various other wireless communication systems which have non-static antenna ports for transmitting a control channel to specific UEs. [0054] Further, some of the various features of the above non-limiting embodiments may be used to advantage without the corresponding use of other described features. The foregoing description should therefore be considered as merely illustrative of the principles, teachings and exemplary embodiments of this invention, and not in limitation thereof.