GB2492967A - Allocation of available television white space (TVWS) based on geographical position tracking - Google Patents

Abstract

A method of controlling allocation of available television white space (TVWS) channels comprises: requesting data of available television white space channels in a geographical tracking area by a television band device 10, 12, 13, 15 (e.g. Mode 1 or Mode 2 personal, portable devices); identifying available television white space channels and base stations 11,14 of at least one cell within the area, including use of television band device location positioning; and defining and allocating at least one available television white space channel for the device in response to the request. The coexistence of cellular secondary systems in the geological tracking area may be checked. Available overlapping white space channels may be determined based on geo-location (positional) accuracy and a cell neighbour list. The request for available white space channels can be evaluated by filtering using the cell neighbor list. Base station 11, 14 network resources may be configured using base station location, cell neighbour list and other, interfering network base stations in an overlapping TV white space channel. Channels may be selected using lowest signal power. Position may be determined based on GPS, evolved observed time difference of arrival, or by cell identity and timing advance.

Description

Mobile Communication Networks

Teclmical Field

The present invention relates to mobile communication networks, and es- pecially to LTE-A (Long Term Evolution) cellular communications in license-exempt TV White Spaces (TYWS) bands, where ion-cellular systems such as WiFi (IEEE 802.11 standard), Zigbee (IEEE 802.15), BlueTooth, and USB wire-less systems may co-exist.

Backiround In mobile communication networks, different frequency bands form a resource tightly govcrned between different uscrs and applications. The govern-ing institutions include scvcral standardizing organizations, c.g. in the USA, the governing institution is the Federal Communications Commission (FCC). There- fore, specific bands are allocated for third (30) and fourth generation (40) cellu-lar wireless networks and for WLAN usage. Also, there are specific frequency bands allocated e.g. for TV broadcasting. Generally it can be considered that for any specified specific mobile communication application, some parts of the spec-trum arc licensed for it and the rest of the spectrum forms unlicensed bands for the application.

An unlicensed band is a shared spectrum where interference from other unknown systems and sources can bc present such as in ISM (Industrial, Scientif-ic and Medical) bands. As licensed band operation has been increasingly utilized, portions of the radio spectrum that remain available have become limited. There-fore, operators, scrvice providers, communication device manufacturers, and communication system manufacturers are all seeking efficient solutions to utilize unlicensed shared bands. Communication on an unlicensed shared band has been generally based on sharing an available radio channel between different commu-nication devices. Different communication devices may utilize a common radio access technology (RAT), but it is also possible that different communication devices utilize different RATs which may have different kinds of limitations and different rules in their operation. In an unlicensed shared band, channel access can be distributed in a manner where communication devices can be configured to detect a channel and utilize a channel reservation scheme known to other communication devices in order to reserve a right to access the channel.

A potential and attractive spectrum resource is the TV white space (TVWS) band which generally means all frequency bands allocated for television broadcast signals but which are locally free in a certain geographical area.

The FCC has defined two concepts for helping to find available channels; a TV band database and a geo-location capability. A TV band database that main-tains rccords of all authorized services in the TV frequency bands is capable of determining the available channels according to a specific geographic location and it provides lists of available channels to TV Band Devices (TVBD) that have been certified under the FCC's equipment authorization procedures. The geo- location capability is defined for some of the TVBDs. A TVBD with such a ca-pability should be able to determine its geographic coordinates within certain level of accuracy, which can be e.g. ± 50 m. The geo-location capability is used with a TV band database to determine the availability of TV channels at a loca-tion of the TVBD.

Several types of TVBDs have been defined by FCC based on their cha-racteristics. In the USA, the general frequency range for television use is between 54 -698 MHz.

A first type ofTVBDs comprises fixed devices. A fixed TVBD is located at a specified fixed location. A fixed TVBD is able to select a channel from the TV band database. Furthermore, it is able to initiate and operate a network by sending enabling signals to other fixed TVBDs or personal/portable TVBDs. Ad- ditionally, it is able to provide a list of available channels to a Mode I person- al/portable device (see below) on which the Mode I device may operate, especial- ly a supplemental list of available channels for Mode I devices. Such a supple-mental list may contain available TV channels that are adjacent to occupied TV channels, for which the fixed TVBD5 cannot operate. For instance, the fixed de-vice may be an access point.

A second type of TVBDs comprises Mode I personal/portable devices.

Such a device does not use any internal geo-location capability or access to a TV band database, so it must obtain a channel list from either a fixed TVBD or from a Mode II personal/portable TVBD (see below). This kind of device may work only as a client/slave and not as a master device.

A third type of TVBDs comprises Mode II personal/portable devices. A Mode II personal/portable device has similar functions as a fixed TVBD, but it does not need to transmit or receive signals at a specified and fixed place. This kind of TVBD can also be an access point, for instance.

A fourth type of TVBDs comprises sensing only devices. Such a device comprises a personal/portable TVBD that uses spectrum sensing for determining a list of available channels. It can use frequency bands 512-608 MHz (in USA, TV channels 21-36) and 614-698 MUz (US TV channels 38-51). It is notable that the spectrum sensing is only defined for personal/portable TVBDs.

The transmission power limits are standardized as follows. For fixed TVBDs, the maximum power delivered to the transmitting (TX) antenna shall not exceed I W. For personal/portable TVBDs, the maximum effective isotropic ra-diated power (EIRP) is 100 mW (20 dBm). If the personal/portable TVBD does not meet the adjacent channel separation requirements (the distance between the TVBD and the TV station is smaller than the minimum distance requirement), the maximum EIRP is set to 40 mW (16 dBm).

The maximum power spectral densities (for any 100 kHz band during any time interval of continuous transmission) for different types of TVBDs are stan-dardized for fixed devices as 12.2 dBm, for personal/portable devices operating adjacent to occupied TV channels as -1.6 dBm, for sensing only devices as -0.8 dBm and for all other personal/portable devices as 2.2 dBm.

IEEE technologies represent an attractive choice for the TVWS due to their listen-before-talk nature to provide an inbuilt Physical Layer (PHY) / Me-dium Access Control (MAC) level co-existence in the unlicensed spectrum. IEEE projects like 802.22, 802.llaf, 802.19.1 and 1900.4a have undertaken actions to address the White Space issues from different points of view.

Solutions for the deployment of LTE wireless nodes such as macro or mi- cro eNodeBs (eNBs; LTE base stations), pico eNBs, and Home eNBs in hetero- geneous networks using the same spectrum are being investigated in 3GPP Re-lease 10 (RP-100383, "New Work Item Proposal: Enhanced ICIC for non-CA based deployments of heterogeneous networks for LTE", RAN#47, March 2010).

Re-use of Release 8/9 techniques, backward compatibility for Release 8/9 ter-minals, and minimum impact of physical layer air interface are key drivers.

1 0 To prevent licensed spectrum scarcity becoming a bottleneck for hetero-geneous networks due to inter-node interference, LTE systems could be deployed in TV White Space (TVWS) bands with the licensed band resources being used during the initial setup. In the USA, the FCC has regulated licensed or license- exempt TV bands for the secondary-system applications (i.e. cellular, WiFi, Wi-Max) on TVBDs.

The following table gives the available TVWS bands in the US (see FCC 10-174, "SECOND MEMORANDUM OPINION AND ORDER", September, 23, 2010). Each TV channel has a 6 MHz bandwidth and it would typically be sufficient for any kind of wireless communication.

Frequency Range (cones-Center Frequency Available bandwidth ponding TV channel numbers) 54-60 MHz (2) 57 MHz 6 MHz 76-88 MHz (5,6) 82 MHz 12 MHz 174-216 MHz (7-13) 195 MHz 42 MHz 470-608 MHz (14-36) 539 MHz 138 MHz 614-698 MHz (38-5 1) 656 MHz 84 MHz Most applications in the TV bands are primary applications in some or all the channels, including TV services, Wireless Medical Telemetry Service (WMTS) and radio astronomy, Private Land Mobile Radio Service (PLMRS) and the Commercial Mobile Radio Service (CMRS) and regional based services. In addition, there are also some existing secondary systems such as wireless micro-phone (channel 7-46) and unlicensed remote control devices (above channel 4).

In prior art, NICT 11-10-1234 ("Channel list request/response for mul-tiple geo-locations", IEEE 802.llat Oct 2010) proposed conditional access to TVWS for thc mode II device to check its location every minute (via OPS or some other way), then check if it locates outside the boundary. If it locates inside the boundary, the device doesn't contact the TVWS database. The boundary is determined from operating geographical areas based on operating channels and indicated in WSM IE (White Space Mapping) for current geo-location (accuracy within ±SOm) using available TVWS channel list WSMI and vicinity geo-location (accuracy less +50m) using available TVWS channel list WSM2. This allows the device to check its position every 60 seconds based on FCC require- ments and to contact the database only if its location is outside the signaled geo-graphical areas. The TVWS database may then need to be queried only every 24 hours.

COGEU ("Cognitive radio systems for efficient sharing of TV white spaces in European context") has proposed a practical approach for geo-location of TVBDs in geographical area (COGEU, FF7 ICT-200S. 1.1, D4.1 Spectrum measurements and anti-interference spectrum database specification, 15 Sep 2010). They recognized that determining that a geographical area is available for White Space Devices (WSD), radio communication depends on signal strength measured at different locations around a given location and compared to some threshold values to establish that the TVBD location probability corresponds to a 70%, 90% or 95% area cell coverage with cell sizes I OOm x I OOm, 200m x 200m or SOOm x 500m, respectively. A geo-location database would work with such a grid, where the device may inform the database on used localization technology, e.g. GPS, cellular based solution Evolved Observed Time Difference Of Arrival (E-OTDOA) using trilateration (based on distances) or network-based cell Identi-ty + Timing Advance (cell ID + TA) using triangulation (based on directions).

The database may subsequently use a look-up table to ascertain the correct loca-tion accuracy. Interference margin to reduce the coverage of the area may be used based on the accuracy of the geo-location, i.e. there may be a smaller list of available TVWS channels within the geographical area. LTE interference to pri- mary systems has also been extensively analyzed. Initial access to the geo-location database by TVBDs by using existing radio interfaces, such as WiFi, Lit or WiMax, has been briefly mentioned in the COGEU approach.

The European Conference of Postal and Telecommunications Administra-tions (CEPT) has indicated that thc geographic area covered by a geo-location database is represented as pixels which are areas of predetermined dimensions (see CEPTIECC Draft Report 159: "Technical and operational requirements for the possible operation of cognitive radio systems in the White spaces of the fit-quency band 470-790 MHz"). Each pixel is associated with a list of available frequencies and other relevant data that are provided to cognitive devices query- ing the database. The exact dimensions of a pixel may depend on planning deci-sions made in populating the database. The main purpose of using a geo-location database for WSD is to ensure that there is no harmful interference from the WSD to the protected services. This is achieved by sharing a minimum amount of information between devices and the database to ensure the correct calculation of available channels. In that sense, the CEPT requirements are more flexible than the FCC fixed requirement for geo-location accuracy of±50m.

The problematic issue of the prior art is handled in the following. To help the TVBDs find available channels, the FCC has introduced the following issues.

TVWS database is available online by the TVBDs (typically via internet connec-tion) that indicate the available channels as a specific geographic location. TVBD geo-location capability is available using GPS or other adequate location posi-tioning methods (i.e. methods which can determine the physical location of a given device) within required accuracy of ±SOnt This is used with the TVWS database to check the available TV channels at a TVBD's location.

In addition, the FCC has defincd thc following requirements for TVBD typcs. Fixed TVBDs arc located at a specified fixed location and must access the TV band database at least once a day to veri' the channel availability. Their scheduling information has to be updated at least every 48 hours. Mode II TVBDs have to check their locations at least every 60 seconds (except in the sleep mode, when the device is inactive but not powered off) and access the TVWS database if the location has changed either through a direct connection (e.g. via DSL line) or through an indirect connection (e.g. via fixed TVBD or another Mode II TVBD). Mode I TVBDs must either receive a contact verifica-tion signal from a Mode II or fixed devicc or contact a Mode II or fixed devicc to re-vcrify/re-establish channel availability at least once in cvcry 60 s period. Sens-ing only TVBDs use spectrum sensing to determine a list of available channels.

They can use the frequency bands 5 12-608 MHz (US TV channels 21-36) and 614-698 MHz (US TV channels 38-51). Spectrum sensing is only defined for personal/portable TVBDs.

These mechanisms aim to set up TVBD connections in TVWS channels when not used by the primary systems, but they have the following limitations.

The geo-location requirement of +50m for Mode II devices may be difficult to achieve by practical positioning methods, e.g. GPS, if locating indoors without good line-of-sight (LOS) to several satellites, or cellular positioning techniques such as OTDOA. In addition, in case the available TVWS channel covers a large area (i.e. radius of>> 50 m), accessing the TVWS database could be done on a need basis to reduce White Space Mapping (WSM) signaling only if Mode II device leaves the available TVWS channel coverage. Furthermore, these mechan-isms do not apply to secondary systems. Cellular network operators may have a cellular database showing their coverage accurately, but they are unlikely to al-low any competitors to use them. WIFi databases including home WiFi networks is not a likely solution.

There is a need for a solution that allows, on the one hand, re-use of exist-ing mechanisms (i.e. TVWS database, TVBD geo-location) to check that TVWS channels are not used by any primary systems in an efficient way, whilst on the

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other hand, it is nccessary to determinc whcthcr available TVWS channcls arc also free from other secondary-system interference.

Summary

According to a first aspect of the invention, there is provided a method of controlling allocation of available television white space channels, which com- prises requesting data of available television white space channels in a geograph-ical tracking area by a television band device, identifying available television white space channels and base stations of at least one cell within the geographical tracking area, including use of a location positioning method for the television band device, and defining and allocating at least one available television white space channel for the television band device as a response to the request.

In an embodiment of the invention, the method further comprises check-ing co-existence of cellular secondary systems in the geographical tracking area.

In an embodiment of the invention, the method thither comprises deter-mining the available overlapping television white space channels based on at least the geo-location accuracy of an apparatus performing the method and a cell neighbor list.

In an embodiment of the invention, the method fhrther comprises evaluat-ing the request according to its geographical tracking area filtering rule using the cell neighbor list, and connecting to the television white space database on behalf of the television band device to request a list of available television white space channels or overlapping television white space channels in the geographical tracking area.

In an embodiment of the invention, the method thrther comprises confi-guring network resources for the base station based on the location of the base station, the cell neighbor list and interfering other network base stations in an overlapping television white space channel.

In an embodiment of the invention, the method further comprises select-ing a television white space channel for the television band device where a lowest signal power transmitted from other network base stations is received.

In an embodiment of the invention, the method further comprises locating the position of a television band device by Global Positioning System, by Evolved Observed Time Difference Of Anival or by cell Identity and Timing Advance method.

In an embodiment of the invention, the method further comprises check-ing the location for a mode II device between predetermined periods of time, and defining the at least one available television white space channel for the mode II device based on location accuracy.

According to a second aspect of the invention, there is provided an appa- ratus for use in controlling allocation of available television white space chan-nels. The apparatus comprises receiving means configured to receive a request of available television white space channels in a geographical tracking area, from at least one television band device. The apparatus also comprises processing means configured to identify available television white space channels and base stations of at least one cell within the geographical tracking area, including use of a loca-tion positioning method for the television band device. The processing means is configured to define and allocate at least one available television white space channel for the television band device as a response to the request.

In an embodiment of the invention, the apparatus further comprises see-ondary user co-ordination means configured to co-ordinate cellular secondary user co-existence on television white space channels at the geographical tracking area.

In an embodiment of the invention, the processing means is configured to determine the available overlapping television white space channels based on at least the geo-location accuracy of the apparatus and a cell neighbor Ust.

In an embodiment of the invention, the processing means is configured to evaluate the request according to its geographical tracking area filtering rule us- ing the cell neighbor list, and the apparatus is configured to connect to the televi-sion white space database on behalf of the television band device to request a list of available television white space channels or overlapping television white space channels in the geographical tracking area.

In an embodiment of the invention, the apparatus further comprises confi-guring means for configuring network resources for the base station based on the location of the base station, the cell neighbor list and interfering other network base stations in an overlapping television white space channel.

In an embodiment of the invention, the apparatus is configured to select a television white space channel for the television band device where a lowest sig-nal power transmitted from other network base stations is received.

According to a third aspect of the invention, there is provided a network, comprising at least one base station, at least one television band device. The net-work frirther comprises an apparatus for television white space mapping for the at least one television band device.

In an embodiment of the invention, the network comprises a secondary system television white space server connectable with the apparatus, the server being configured to co-ordinate cellular secondary user co-existence on television white space channels at the geographical tracking area.

In an embodiment of the invention, the network comprises positioning means configured to locate the television band device by Global Positioning Sys-tem, by Evolved Observed Time Difference Of Arrival or by cell Identity and Timing Advance method.

In an embodiment of the invention, the positioning means is configured to cheek the location for a mode II device between predetermined periods of time, and the apparatus is configured to define the at least one available television white space channel for the mode II device based on location accuracy.

According to a fourth aspect of the invention, there is provided a comput- er program product comprising a non-transitory computer-readaNe storage me- dium having computer readable instructions stored thereon, the computer reada- ble instructions being executable by a computerized device to cause the compute-rized device to perform a method for controlling allocation of available television white space channels, the method comprising: requesting data of available television white space channels in a geo-graphical tracking area by a television band device; identifying available television white space channels and base stations of at least one cell within the geographical tracking area, including use of a location positioning method for the television band device; and defining and allocating at least one available television white space chan-nd for the television band device as a response to the request.

According to a fifth aspect of the invention, there is provided computer software adapted to perform the method of the first aspect of the invention.

It is possible to combine one or more of the embodiments and aspects dis-closed above to form one or more further embodiments of the present invention.

Brief Descuiption of thc Drawings The accompanying drawing, which is included to provide a further under-standing of the invention and constitute a part of this specification, illustrates embodiments of the invention and together with the description helps to explain the principles of the invention. The examples shown in the drawing are not the only possible embodiments of the invention and the invention is not considered to be limited to the presented embodiments.

Fig. 1 illustrates the principle of White Space Mapping Geographical Tracking Area (WSM GTA) according to the invention.

Detailed Description

Rcfcrcncc will now be made in detail to the embodiments of the prcscnt invention, examples of which are illustratcd in thc accompanying drawing.

The present invention introduces a method, apparatus a network, a com- puter program product and computer software for controlling allocation a televi-sion white space channel for a TV band device, with the help of geo-positioning and also, by taking possible secondary system interference into account.

In the present invention, it is assumed that the mode II device can be, e.g. a Femto Access Point with LTE local-area capability or it can connect to a mode II device being e.g. a Femto Access Point on an available TVWS channel in the TVWS band. It is further assumed that the mode II device can connect to a wide-areaLTEeNBonacellularbandasanormalLTEuserEquipment(UE)toset up a cell in a TVWS band. An embodiment of the present invention is outlined in the following procedure.

As a first step in this embodiment of the invention, available overlapping TVWS channels within WSM OTA are identified. At first the mode II device accesses the TVWS database via the LTE network acting as a "proxy". The TVWS database detemiines a list of available TVWS overlapping channels in Whitc Space Mapping Geographical Tracking Area (WSM-GTA) based on the mode II device geo-loeation accuracy and LTE cell neighbor list. The TVWS database indicates in the channel list response an information element (IE) to the LU "proxy" which forwards to the mode II device the following lists: (i) the TVWS channel list WSMI based on geo-location accuracy of ±50m; (ii) the overlapping TVWS channel list, WSM2, with geo-location based on LTE ceilcoverage accuracy; and (iii) the eNB IDs of the LTE cell within the WSM (IrA or alternatively, these eNB IDs are added to the if by the Lit "proxy" to allow more efficient TVWS database signaling, as this information is already stored in the Mobile Management Entity (MME).

As a second step in this embodiment, co-existence with other cellular secondary systems within WSM (IrA is checked. The LU Mobile Management Entity -Non-Access Stratum (MME-NAS) within the WSM CA configures resources to mode II devices in a TVWS band via higher layer signaling on cellu-lar band based on the following: (i) Mode II device location.

(ii) LTE cell neighbor list of the LTE-attached mode II device.

(iii)Other cellular secondary systems likely to interftre with a mode II device by indicating a list of other network eNB IDs whose position or cell cov-erage area matches that of the eNB ll)s in the LTE home network. The cell neighbor list and overlapping TVWS channel list (WSM2) can be used. This requires some inter-network co-ordination between the LTE home network and other network (e.g. LTE, WiMax). In this way, other network eNBs will not use the same overlapping TVWS channels with their own network eNBs, and thus, interference is avoided.

Furthermore, the mode II device keeps attached to the LTE cNB in case re-configuration of the resources in the TVWS band is needed, i.e. co-ordination of WSM GTAs with other operator networks is performed for avoiding inter-secondary system interference on overlapping TVWS channels.

As a third step of the procedure, a Secondary System TVWS Server (SSTS) allows network operators to co-ordinate cellular secondary uscr co-existence on TYWS at WSM GTA level. Furthermore, the TVWS resource configuration is transparcnt to the access layer, i.e. MME/NAS signaling is used with no TVWS-specific Access Stratum (AS) signaling.

The SSTS may be outside the network domain or within the network domain.

This may depend on the implementation and specification of the interfaces be- tween the SSTS and MME within a network domain or between network do-mains.

The mode II devices use LTE cell coverage (eNB#i in WSM-GTA) in case resources are configured on overlapping TYWS channels (WSM2 list) for more efficient positioning-related signaling, or if positioning measurements are not possible, or positioning measurements are limited by mode II device battery ca-paeity or if the mode II device is moving. Otherwise, mode II devices can use TVWS channels based on their geo-location accuracy, which depends on the type of the positioning method and estimated position error (WSMI list). More details on different embodiments are provided later.

To limit interference from secondary cellular systems, the mode II device may cheek whether other network eNBs have coverage on the overlapping TVWS channels based on their eNB IlJs as signaled by the MME NAS. It may select the overlapping TVWS channels with the lowest received signal power from these other network eNBs. More details on these issues are also provided later.

Note that the cellular TVWS server is for co-existence of cellular secondary users to minimize their transmissions on TVWS channels interfering with each other. This is a different entity from the TVWS server used for determination of the available TVWS channels to minimize interference from secondary user transmissions to the primary users.

Further embodiments for the implementation comprise the LTE network acting as "proxy" for a mode II device. The LTE network is aware at the MME-NAS layer of the mode II device, as it needs to send eNB#i of the LTE cells within WSM GTA. The mode II devices are transparent to eNBs and there is no TVWS-speeific AS signaling.

As a proxy, the LTE system acts as an intermediary for TVWS channel list requests by the (client) mode II device which wants resources from the TVWS database. The LTE proxy evaluates a request according to its WSM OTA filtering rule using LTE cell neighbor list and connects to the TYWS database on behalf of the (client) mode II device to request the list of available TYWS chan-nels or overlapping TYWS channels in WSM GTA. Hence, in this embodiment, the LTE system acting as a proxy is more than just a basic network access.

In the LTE system, the MM E-NAS sends a list of eNB#i in WSM UTA and geo-location of mode II device to the TVWS database on behalf of the client mode II device in one embodiment. Then, the TYWS database works out the overlapping TVWS channels and sends that information and the eNB#i list in the channel list response IF to LTE proxy which forwards it to the client mode II device.

In this embodiment, the LTE network operator only needs to store the LTE eNB#i cell area (i.e. co-ordinates) in the TVWS database once every 24 hours to allow for changes in LTE coverage of LTE cells (e.g. rainy weather con-ditions and changes in vegetation are known factors affecting cellular coverage).

This allows efficient TVWS-specific signaling, as the LTE proxy only sends the list of eNB#i within WSM GTA of mode II device's needs to the TVWS data-base, which can work out the overlapping channels based on eNB#i IDs in WSM GTA.

The mode II devices do not need to provide the list of eNB#i in WSM-GTA. That information is already available in MME based on neighr list for LTE cell handover. In the handover procedure, the mode II device is required to make Reference Signal Received Power (RSRP) measurements based on neigh-bor-cell Cell-specific Reference Signal (CRS) and report measurements to the LTE system. This allows the MME to make handover decisions for the mode II device. The mode II device may do GPS fix or Reference Signal Time Difference (RSTD) measurements in E-OTDOA and report them to the LTE network, where an Evolved-Serving Mobile Location Centre (E-SMLC) entity works out its gco-location.

The E-SMLC entity may tell the MME about the location of the mode II device with its estimated accuracy. For example, if it is assumed that the GPS fix is done with a good LOS to a large number of satellites, the geo-location can be expected to be ±50m. On the other hand, in indoor conditions or in the city center with tall buildings nearby, thcre may only be a good LOS to a small number of satellites, and the geo-location accuracy can be expected to be less than ±50m. If it is assumed that E-OTDOA is done with a good Positioning Reference Signal (PRS) strength at the mode II device receiver and small cell size, the geo-location accuracy can be expected to be within ±SOm. Otherwise, the geo-loeation accura-cy could be within ±150m or less. Furthermore, if the cell ID + TA positioning method is applied, the geo-location accuracy could be assumed to be within a few hundred metcrs or less based on the cell size (pico eNB, micro eNB, or macro eNB). In case the cell size is a home eNB (HeNB), the accuracy may depend on whether the location of the I-leNB is known to the LTE network with some accu-racy.

In one embodiment of the invention, based on the positioning method (e.g. GPS, E-OTDOA, cell ID + TA), the evolved Serving Mobile Location Cen- ter (eSMLC) may work out an estimated positioning error and take this into ac-count in the geo-location accuracy of the mode II device,.

The mode II device may get the overlapping TVWS resources in the over-lapping TVWS channel list, W52, using LTE cell coverage accuracy in WSM GTA based on its neighbor cell list. In case a more efficient positioning signaling is required by the LTE nctwork to reduce signaling overhead (in 3GPP Rel-9, positioning is meant only for emergency calls, and not for continuous use in tracking the devicc movements). In ease the mode II device cannot do the GPS fix (an indoors scenario or a battery-powered device may not allow continuous GPS measurements) or RSTD measurements (OTDOA positioning is not sup-ported by the network, or a battery-powered device may not aflow continuous RSTD measurements).

A further embodiment for the implementation handles co-existence with other secondary cellular systems. In a typical cellular scenario, a situation can happen, where home network cannot be found by an LTE device. In this scenario, the LTE device can look for other LTE cellular networks or other cellular net-works such as GERAN or UTRAN provided by the home network operator or other network operators. Then, intra-Radio Access Technology (R&i) handover 1 0 assuming LTE system or inter-Radio Access Technology (RAT) handovcr as-suming TJTRAN or GERAN systems may proceed based on roaming agreements between the home network operators and the other network operators. Possibly, handover could be carried out between the LTE system and WiMax system based on their deployment and LTE device capability, i.e. a multi-mode device support- ing e.g. LTE, GERAN and UTRAN. Hence, the support of intra-RAT (e.g. han-dover or roaming within the same radio access technology, like within the LTE network) and inter-RAT (e.g. roaming between different radio access technolo-gies, like between LTE and GSM) procedures including device measurements are already specified for cellular technologies (such as for LTE, IJTRAN and GE-RAN).

At the following, we consider the support of the intra-RAT handover on TYWS shared bands. Assuming deployment of an LTE home network and other LTE networks, the mode II device may try to detect the synchronization signals and reference signals transmitted by these other network eNB transmissions on the overlapping TVWS channels based on their eNB IDs as signaled by the MME NAS. Such an approach is efficient as the mode II device only needs to try to detect transmissions from a few eNBs (e.g. in LTE, CRS as their name indicate, are cell specific based on eNB IDs) and not exhaustively try every possible cell ID (e.g. LTE has 501 possible cell IDs). The mode II device may select the over- lapping TYWS channels with the lowest received signal power from these other-network eNBs to limit interference from other LTE network secondary cellular systems, i.e. based on Primary/Secondary-Synchronisation Chamiel (P-SCI-1/S- SCH) detection!br time and frequency synchronization and or Cell-specific Ref- erence Signal (CRS) -based Reference Signal Received Power (RSRP) measure-ment. In another embodiment, the radio access technology of other networks may be other cellular systems such as CIERAN or UTRAN, if considered by the indus-try and regulated for deployment in TVWS bands.

A similar approach may be taken if we consider support of inter-RAT handover on TVWS shared bands between LTE home network and other WiFi network. The MME NAS may indicate to the mode II device thc pilot sequences used by the WiMax eNBs which are likely to be transmitted on the overlapping TVWS channels based on the mode II device geo-location.

A firther embodiment for the implementation of the invention comprises a determination of WSM 0Th. The WSM Geographical Tracking Area (WSM-OTA) principle is illustrated in Figure 1. A WSM-CITA consists of a fixed eNB 11, 14 (numbered as #i where i=1, 2, ..., N) sharing overlapping TVWS channels (marked as six channels: no. 3... 8). There are two WSM GTAs #1 and #2 shown in Figure 1. Within coverage of a WSM (IrA, there may be mode 110, 13 andmodelldevicesl2, 15.

The mode II device indicates its geo-location with its location accuracy based on the localization method (e.g. OPS, cell ID + TA, E-OTD) in channel list query IE to the TVWS database via Lit proxy". The TVWS database selects available TVWS channels accordingly and indicates the overlapping TVWS channel list within WSM GTA (i.e. available to mode II devices anywhere within WSM GTA), available TVWS channel list (i.e. available to mode II devices based on their geo4ocation and location accuracy), and eNB#i IDs of eNBs with-in the WSM GTA to the mode IT device in the channel list response JE via Lit proxy". The eNB#i H)s allow seamless use of overlapping TVWS channels by the mode II devices within the WS1vI GTA. This suits moving mode II devices (i.e. Femto AP on a moving train or generally a device equipped with geo-location and capability to access TVWS and connect to mode I devices), which can use overlapping TVWS channels without the need for TVWS channel switch-over. A requirement for a mode II device using overlapping TVWS chan-nels is the checking of its location every 60s.

For example, the mode II device 15 in WSM GTA #1 in Figure 1 may in- dicate the available TYWS channels as channels 4, 5, 6 and 7, and the used chan-nels are channels 3 and 8, based on reported accuracy as follows: o Accuracy within + l000m, channels 5, 6 are available (e.g. Macro cell or WSM-GTA accuracy).

o Accuracy within + 250m for channels 5, 6, 7 (roughly self-positioned femto eNB!WLAN accuracy).

o Accuracy within + 150m for channels 4, 5, 6, 7 (E-OTDA).

o Accuracy within + 50m for channels 4, 5, 6, 7 (outdoor GPS accuracy).

The available TVWS channels for the cNB 14 are channels 5 and 6 in this example. The available TVWS channels for the mode I dcvice 13 (the UE) are in this example the same channels as for the mode II device, i.e. channels 4-7. As can be seen from Figure 1, in this embodiment the allowed Tx power for mode I and mode TI devices is equal. As said above, there is no requirement for the geo- location determination for mode I devices, while for mode II devices a strict re-quirement exists in the shown embodiment.

The main advantages of the present invention are the capability to use the LTE network as a "proxy" to allow efficient TVWS-specific MIvIE-NAS and positioning signaling of the mode II device. Furthermore, mode [I devices are transparent to the access layer, i.e. no TYWS-specifie AS signaling is needed.

Furthermore, the overlapping TYWS channel based on the LTE coverage accura-cy can re-use the neighbor cell list based on the specified LTE measurements for cellular handover with no additional cost in terms of signaling over the air inter- face and also with regard to the mode II device implementation. Yet another ad-vantage is that the invention enables practical and flexible allocation of available TYWS channels to the mode II device in case the geo-location accuracy cannot meet the strict FCC requirements. Otherwise, mode II devices can use TVWS channel resources based on geo-location accuracy. Finally, the LTE "proxy" may further help the mode II device to select TVWS channels with minimum interfe- rence from other network secondary systems via co-ordination with other net-work secondary systems in a new Secondary System TYWS Server entity.

In an embodiment, the apparatuses, method steps (different functionalities of the base stations/nodes), the computer program product and computer software according to the invention can be implemented by at least one separate or em-bedded hardware module in at least one device of the mobile communication network. In one embodiment, the functionalities are implemented in a ehipset for different network devices.

A separate or an embedded control unit may perform the above men- tioned method steps where applicable. In an embodiment, the apparatus compris-es a memory, and at least one processor configured to execute applicable method steps according to the invention. Furthermore, the method according to the inven- tion can be implemented with one or several computer programs which are ex-ecuted by the at least one processor. The computer program(s) can be stored on at least one computer readable medium such as, for example, a memory circuit, memory card, magnetic or optical disk. Some functional entities may be imple-mented as program modules linked to another functional entity. The functional entities may also be stored in separate memories and executed by separate pro- cessors, which communicate, for example, via a message bus or an internal net- work within the network node. An example of such a message bus is the Peri-pheral Component Interconnect (PCI) bus.

The exemplary embodiments of the invention can be included within any suitable device, for example, including any suitable servers, workstations, PCs, laptop computers, PDAs, Internet appliances, handheld devices, cellular tele-phones, wireless devices, other devices, and the like, capable of performing the processes of the exemplary embodiments, and which can communicate via one or more interface mechanisms, including, for example, Internet access, telecommu-nications in any suitable form (for instance, voice, modem, and the like), wireless communications media, one or more wireless communications networks, cellular communications networks, 3G communications networks, 4G communications networks, Public Switched Telephone Network (PSTN5), Packet Data Networks (PDNs), the Internet, intranets, a combination thereof, and the like.

It is to be understood that the exemplary embodiments are for exemplary purposes, as many variations of the specific hardware used to implement the cx-emplary embodiments are possible, as will be appreciated by those skilled in the hardware arts. For example, the functionality of one or more of the components of the exemplary embodiments can be implemented via one or more hardware devices.

The exemplary embodiments can store information relating to various processes described herein. This information can be stored in one or more mem-ories, such as a hard disk, optical disk, magneto-optical disk, RAM, and the like.

One or more databases can store the information used to implement the exem- plary embodiments of the present invention. The databases can be organized us-ing data structures (e.g., records, tables, arrays, fields, graphs, trees, lists, and the like) included in one or more memories or storage devices listed herein. The processes described with respect to the exemplary embodiments can include ap-propriate data structures for storing data collected and/or generated by the processes of the devices and subsystems of the exemplary embodiments in one or more databases.

All or a portion of the exemplary embodiments can be implemented by the preparation of application-specific integrated circuits or by interconnecting an appropriate network of conventional component circuits, as will be appreciated by those skilled in the electrical arts.

As stated above, the components of the exemplary embodiments can in-clude computer readable medium or memories according to the teachings of the present invention and for holding data structures, tables, records, and/or other data described herein. Computer readable medium can include any suitable me-dium that participates in providing instructions to a processor for execution. Such a medium can take many forms, including but not limited to, non-volatile media, volatile media, transmission media, and the like. Non-volatile media can include, for example, optical or magnetic disks, magneto-optical disks, and the like. Vo-latile media can include dynamic memories, and the like. Transmission media can include coaxial cables, copper wire, fiber optics, and the like. Transmission media also can take the form of acoustic, optical, electromagnetic waves, and the like, such as those generated during radio frequency (RF) communications, infra- red OR) data communications, and the like. Common forms of computer-readable media can include, for example, a floppy disk, a flexible disk, hard disk, magnetic tape, any other suitable magnetic medium, a CD-ROM, CDRW, DVD, any other suitable optical medium, punch cards, paper tape, optical mark sheets, any other suitable physical medium with patterns of holes or other optically re-cognizable indicia, a RAM, a PROM, an EPROM, a FLASH-EPROM, any other suitable memory chip or cartridge, a canier wave or any other suitable medium from which a computer can read.

While the prescnt inventions have been described in connection with a number of exemplary embodiments, and implementations, the present invention 1 0 are not so limited, but rather cover various modifications, and equivalent ar-rangements, which fall within the purview of prospective claims.

It is obvious to a person skilled in the art that with the advancement of technology, the basic idea of the invention may be implemented in various ways.

The invention and its embodiments are thus not limited to the examples described above; instead they may vary within the scope of the claims.

Claims (2)

1. <claim-text>claims 1. A method of controlling allocation of available television white space channels, the method comprising: requesting data of available television white space channels in a geographi-cal tracking area by a television band device (10, 12, 13, 15); identifying available television white space channels and base stations (11, 14) of at least one cdl within the geographical tracking area, including use of a location positioning method for the television band device (10, 12, 13, 15); and defining and allocating at least onc available television white space channel for the television band device (10, 12, 13, 15) as a response to the request.</claim-text> <claim-text>2. The method according to claim 1, further comprising checking co-existence of cellular secondary systems in the geographical tracking area.</claim-text> <claim-text>3. The method according to claim I or 2, further comprising deter-mining the available overlapping television white space channels based on at least the geo-location accuracy of an apparatus and a cell neighbor list.</claim-text> <claim-text>4. The method according to claim 3, further comprising: evaluating the request according to its geographical tracking area filtering rule using the cell neighbor list; and connecting to the television white space database on behalf of the televi-sion band device (10, 12, 13, 15) to request a list of available television white space channels or overlapping television white space channels in the geographi-cal tracking area.</claim-text> <claim-text>5. The method according to any preceding claim, further comprising configuring network resources for the base station (11, 14) based on the location of the base station (11, 14), the cell neighbor list and interfering other network base stations in an overlapping television white space channel.</claim-text> <claim-text>6. The method according to any preceding claim, further comprising selecting a television white space channel for the television band device (10, 12, 13, 15) where a lowest signal power transmitted from other network base stations is received.</claim-text> <claim-text>7. The method according to any preceding claim, further comprising locating the position of a television band device (10, 12, 13, 15) by Global Posi-tioning System, by Evolved Observed Time Difference Of Arrival or by cell Identity and Timing Advance method.</claim-text> <claim-text>8. The method according to claim 7, further comprising: checking the location for a mode II device (12, 15) between predeter-mined periods of time; and defining the at least one available television white space channel for the mode II device (12, 15) based on location accuracy.</claim-text> <claim-text>9. An apparatus for use in controlling allocation of available televi-sion white space channels, the apparatus comprising: receiving means configured to receive a request of available television white space channels in a geographical tracking area, from at least one television band device (10, 12, 13, 15); and processing means configured to: identify available television white space channels and base stations (11, 14) of at least one cell within the geographical tracking area, including use of a location positioning method for the television band device (10, 12, 13, 15); and define and allocate at least one available television white space chan- nel for the television band device (10, 12, 13, 15) as a response to the re-quest.</claim-text> <claim-text>10. The apparatus according to claim 9, wherein the apparatus further comprises secondary user co-ordination means configured to co-ordinate cellular secondary user co-existence on television white space channels at the geographi-cal tracking area.</claim-text> <claim-text>11. The apparatus according to claim 9 or 10, wherein the processing means is configured to determine the available overlapping television white space channels based on at least the geo-location accuracy of the apparatus and a cell neighbor list.</claim-text> <claim-text>12. The apparatus according to claim 11, wherein the processing means is configured to evaluate the request according to its geographical tracking area filtering rule using the cell neighbor list; and the apparatus is configured to connect to the television white space data-base on behalf of the television band device (10, 12, 13, 15) to request a list of available television white space channels or overlapping television white space channels in the geographical tracking area.</claim-text> <claim-text>13. The apparatus according to any of claims 9 to 12, wherein the ap-paratus further comprises configuring means for configuring network resources for the base station (11, 14) based on the location of the base station (11, 14), the cell neighbor list and interfering other network base stations in an overlapping television white space channel.</claim-text> <claim-text>14. The apparatus according to any of claims 9 to 13, wherein the ap-paratus is configured to select a television white space channel for the television band device (10, 12, 13, 15) where a lowest signal power transmitted from other network base stations is received.</claim-text> <claim-text>15. A network, comprising: at least one base station (11, 14); atleastonetelevisionbanddevice(10, 12,13,15); and an apparatus for television white space mapping for the at least one tele-vision band device (10, 12, 13, 15).</claim-text> <claim-text>16. The network according to claim 15, wherein the network further comprises a secondary system television white space server connectable with the apparatus, the server being configured to co-ordinate cellular secondary user co-existence on television white space channels at the geographical tracking area.</claim-text> <claim-text>17. The network according to claim 15 or 16, wherein the network further comprises location positioning means configured to locate the television band device (10, 12, 13, 15) by Global Positioning System, by Evolved Observed Time Difference Of Arrival or by cell Identity and Timing Advance method.</claim-text> <claim-text>18. The network according to claim 17, wherein the location position- ing means is configured to check the location for a mode II device (12, 15) be-tween predetermined periods of time; and 1 5 the apparatus is configured to define the at least one available tele- vision white space channel for the mode II device (12, 15) based on location ac-curacy.</claim-text> <claim-text>19. A computer program product comprising a non-transitory comput- er-readable storage medium having computer readable instructions stored there- on, the computer readable instructions being executable by a computerized de- vice to cause the computerized device to perform a method for controlling alloca-tion of available television white space channels, the method comprising: requesting data of available television white space channels in a geo-graphical tracking area by a television band device (10, 12, 13, 15); identifying available television white space channels and base stations (11, 14) of at least one cell within the geographical tracking area, including use of a location positioning method for the television band device (10, 12, 13, 15); and defining and allocating at least one available television white space chan-nd for the television band device (10, 12, 13, 15) as a response for the request.</claim-text> <claim-text>20. Computer software adapted to perform the method of any of claims lto8.Amended claims have been filed as follows: Claims 1. A method of controlling allocation of available television white space channels, the method comprising: requesting data of available television white space channels in a geographi-cal tracking area by a television band device (10, 12, 13, 15); identiring available television white space channels and base stations (11, 14) of at least one cell within the geographical tracking area, including use of a location positioning method for the television band device (10, 12, 13, 15); determining available overlapping television white space channels based on at least the geo-location accuracy of the television band device and a cell neigh-bor list; and defining and allocating at least one available television white space channel for the television band device (10, 12, 13, 15) as a response to the request. r(\J
2. 2. The method according to claim 1, further comprising checking co-existence of cellular secondary systems in the geographical tracking area. Ct)3. The method according to claim I or 2, ifidher comprising: evaluating the request according to a geographical tracking area filtering rule using the cell neighbor list; and connecting to the television white space database on behalf of the televi-sion band device (10, 12, 13, 15) to request a list of available television white space channels or overlapping television white space channels in thc geographi-cal tracking area.4. The method according to any preceding claim, further comprising configuring network resources for the base station (11, 14) based on the location of the base station (11, 14), the cell neighbor list and interfering other network base stations in an overlapping television white space channel.5. The method according to any preceding claim, further comprising selecting a television white space channel for the television band device (10, 12, 13, 15) where a lowest signal power transmitted from other network base stations is received.6. The method according to any preceding claim, fUrther comprising locating the position of a television band device (10, 12, 13, 15) by Global Posi-tioning System, by Evolved Observed Time Difference Of Arrival or by cell Identity and Timing Advance method.7. The method according to claim 6, further comprising: checking the location for a mode II television band device (12, 15) be-tween predetermined periods of time; and defining the at least one available television white space channel for the mode 11 device (12, 15) based on location accuracy.C') 8. An apparatus for use in controlling allocation of available televi- 0 sion white space channels, the apparatus comprising: receiving means configured to receive a request of available television white space channels in a geographical tracking area, from at least one television band device (10, 12, 13, 15); and processing means configured to: identi' available television white space channels and base stations (11, 14) of at least one cell within the geographical tracking area, including use of a location positioning method for a television band device (10, 12, 13, 15); determine available overlapping television white space channels based on at least the geo-loeation accuracy of the television band device and a cell neighbor list; and define and allocate at least one available television white space chan- nel for the television band device (10, 12, 13, 15) as a response to the re-quest.9. The apparatus according to claim 8, wherein the apparatus further comprises secondary user co-ordination means configured to co-ordinate cellular secondary user co-existence on television white space channels at the geographi-cal tracking area.10. The apparatus aecord[ng to claim 8 or 9, wherein the processing means is configured to evaluate the request according to a geographical tracking area filtering rule using the cell neighbor list; and çs,j the apparatus is configured to connect to the television white space data- 1-base on behalf of the television band device (10, 12, 13, 15) to request a list of (sJ available television white space channels or overlapping television white space O channels in the geographical tracking area. Ct)O II. The apparatus according to any of claims 8 to 10, wherein the ap-paratus further comprises configuring means for configuring network resources for the base station (11, 14) based on the location of the base station (11, 14), the cell neighbor list and interfering other network base stations in an overlapping television white space channel.12. The apparatus according to any of claims 8 to 11, wherein the ap-paratus is configured to select a television white space channel for the television band device (10, 12, 13, 15) where a lowest signal power transmitted from other network base stations is received.13. A computer program product comprising a non-transitory comput- er-readable storage medium having computer readable instructions stored there- on, the computer readable instructions being executable by a computerized de- vice to cause the computerized device to perform a method for controlling alloca-tion of available television white space channels, the method comprising: requesting data of available television white space channels in a geo-graphical tracking area by a television band device (10, 12, 13, 15); identifying available television white space channels and base stations (11, 14) of at least one cell within the geographical tracking area, including use of a location positioning method for the television band device (10, 12, 13, 15); determining available overlapping television white space channels based on at least the geo-location accuracy of the television band device and a cell neighbor list; and defining and allocating at least one available television white space chan-nel for thc television band dcvicc (10, 12, 13, 15) as a response for the requcst. (414. Computer software adapted to perform the method of any of (4 claims ito 7. C)</claim-text>