Classifications

• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04B—TRANSMISSION
  • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
  • H04B1/69—Spread spectrum techniques
  • H04B1/713—Spread spectrum techniques using frequency hopping
  • H04B1/7143—Arrangements for generation of hop patterns
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04B—TRANSMISSION
  • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
  • H04B1/69—Spread spectrum techniques
  • H04B1/713—Spread spectrum techniques using frequency hopping
  • H04B1/715—Interference-related aspects
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L5/00—Arrangements affording multiple use of the transmission path
  • H04L5/0001—Arrangements for dividing the transmission path
  • H04L5/0003—Two-dimensional division
  • H04L5/0005—Time-frequency
  • H04L5/0007—Time-frequency the frequencies being orthogonal, e.g. OFDM(A), DMT
  • H04L5/0012—Hopping in multicarrier systems
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W16/00—Network planning, e.g. coverage or traffic planning tools; Network deployment, e.g. resource partitioning or cells structures
  • H04W16/14—Spectrum sharing arrangements between different networks
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W72/00—Local resource management
  • H04W72/12—Wireless traffic scheduling
  • H04W72/1263—Mapping of traffic onto schedule, e.g. scheduled allocation or multiplexing of flows

Definitions

• Embodiments relate generally to wireless communication systems, methods, devices and computer programs, and more specifically relate to frequency hopping in unlicensed radio spectrum/bands.
• E-UTRAN evolved universal terrestrial radio access network
• WiFi wireless fidelity IEEE 802.11
• FIG. 1A illustrates such a heterogeneous environment in which a UE 20 is operating at a location at which it can communicate with a macro eNB 22 and also with a home eNB 26. There may also be additional micro and/or pico cells in the same region. Whether or not the micro and pico eNBs are implemented as remote radio heads under control of the macro eNB, such a heterogeneous radio environment presents a challenging interference scenario.
• Mitigating this interference is now a work item in the 3 GPP [see document RP- 100383, entitled NEW WORK ITEM PROPOSAL: ENHANCED ICIC FOR NON-CA BASED DEPLOYMENTS OF HETEROGENEOUS NETWORKS FOR LTE; RAN#47; Vienna, Austria; 16-19 March 2010]. Briefly, it shall consider techniques used in earlier releases (Release 8/9) and shall ensure backward compatibility for Release 8/9 terminals as well as minimize impact to the physical layer air interface.
• Unlicensed spectrum goes by several names such as license-exempt and shared bands, and by example include what is known as TV white spaces and the ISM bands (both 2.4 GHz under IEEE 802.1 lb and 802.1 lg; and 5 GHz under IEEE 802.1 la). Interference may arise in the license-exempt bands due to devices operating in co-existing non-cellular systems, such as WiFi (IEEE 802.11), Zigbee (IEEE 802.15), Bluetooth, and USB wireless systems.
• LTE cellular-traffic offloading to a license-exempt band is attractive for the increased bandwidth it offers, provided communications can be made reasonably reliable.
• the LTE eNB may be used to set up an LTE connection on the license-exempt band so as to retain control of the offloaded cellular-based traffic. But still there needs to be some solution to minimize interference between the LTE eNB and its device transmissions and any non-cellular devices in the license-exempt band, despite the fact that co-ordination with non-cellular systems on that license-exempt band may not be possible.
• LTE Long Term Evolution
• CA carrier aggregation CA
• Figure IB illustrates the general CA concept for LTE/LTE-A.
• PCell (alternatively termed a primary component carrier or PCC) which by example is backward-compatible with LTE Release 8/9 UEs (and therefore 20 MHz in bandwidth). That same UE may also have in its assigned set SCell#l, SCell#2 and SCell#3 (alternatively termed secondary component carriers SCCs), which for completeness SCell#3 is exemplarily shown as being non-contiguous in frequency with the other CCs. Any number of the SCells or none of them may be active for that UE at any given time, as coordinated with the macro eNB 22.
• PCC primary component carrier
• Every UE 20 is to have its assigned PCell always active, and so the legacy UEs will be assigned one backward-compatible CC (e.g., its PCell) and no others. It is expected for 3 GPP Release 11 (LTE -A) that there will be the capability for cross scheduling across Cells/CCs, and also that the different Cells/CCs may have different UL/DL configurations.
• LTE -A 3 GPP Release 11
• the macro eNB 22 of Figure 1 A may be operating on the PCell and one or more SCells while the HeNB 26 of Figure 1A is operating on a different SCell as an interference mitigation scheme.
• Another scheme in IEEE 802.1 laf is to have the various devices contact a TVWS database to determine the primary systems (i.e. TV broadcasting) and then rely on Carrier Sensing Multiple Access/Collision Avoidance (CSMA/CA) mechanisms to avoid inter- WiFi system interference [see for example document IEEE 802.11-1 l-0089r0 entitled l lAF COEXISTENCE ASSURANCE DOCUMENT, by Cisco Systems and Research In Motion, 19 January 2011].
• CSMA/CA Carrier Sensing Multiple Access/Collision Avoidance
• an apparatus for use in controlling an access node comprising a processing system, for example including at least one processor and a memory storing a set of computer instructions.
• a computer program product comprising a non-transitory computer-readable storage medium having computer readable instructions stored thereon, the computer readable instructions being executable by a computerized device to cause the computerized device to perform the method of the second embodiments.
• Figure 1 A illustrates a heterogeneous network in which a UE is in a region covered by a macro eNB and a home eNB, and is an environment in which embodiments may be practiced with advantage.
• Figure IB is a schematic frequency diagram showing a carrier aggregation system in which some component carriers lay in a licensed band and some lay in unlicensed bands.
• Figure 1C is a schematic diagram of a frequency hopping approach under discussion for aperiodic sounding reference signals SRSs in which each transmission follows an individual hop in a pattern but is sent only when a separate SRS trigger is received.
• Figure 2 is a logic flow diagram illustrating the operation of a method, and a result of execution by an apparatus of a set of computer program instructions embodied on a computer readable memory, in accordance with embodiments.
• Figure 4 is a schematic diagram illustrating cross scheduling on a SCell in the license-exempt band from a PDCCH sent on a PCell in the licensed band.
• Figure 5 is a schematic diagram illustrating differences between a standalone component carrier and an extension component carrier.
• Figure 6 is a simplified block diagram of a UE, a home eNB and a macro eNB with its associated higher network node, which are exemplary electronic devices suitable for use in practicing embodiments.
• frequency hopping can be used in addition to CC segregation and/or CSMA/CA.
• LTE transmissions use frequency agility to minimize interference to co-existing WiFi systems on license-exempt bands.
• the parameters of such transmission may be optimized based on measurements of co-existing WiFi system(s).
• Frequency hopping has been used in GSM systems on the cellular band, including related concepts such as dynamic channel allocation (DC A) with FH pattern adaptation and dynamic frequency hopping using slow FH and modifying the utilized frequency-hop patterns based on rapid frequency quality measurements [see for example FUNDAMENTALS OF DYNAMIC FREQUENCY HOPPING IN CELLULAR SYSTEMS, by Zoran Kostic, Ivana Marie, and Xiaodong Wang; IEEE Journal on Selected Areas in Communications, vol. 19, No. 11; November 2001].
• DC A dynamic channel allocation
• the WLAN system IEEE 802.11 series
• FH on the physical layer in which the whole ISM band is divided for FH purposes into hopping channels of 1 MHz each with a fixed hopping time of 0.4 seconds.
• the hopping process is restricted to no longer than 224 s per channel hop.
• FH scheme does not use any selective or intelligent hopping. See for example Frequency Hopping Spread Spectrum (FHSS) vs. Direct Sequence Spread Spectrum (DSSS) in Broadband Wireless Access (BWA) and Wireless LAN (WLAN) by Sorin M. Schwartz [see http:www//sorin-schwartz.com/white_papers/fhvsds.pdf, undated but last visited April 29, 2011].
• FHSS Frequency Hopping Spread Spectrum
• DSSS Direct Sequence Spread Spectrum
• BWA Broadband Wireless Access
• WLAN Wireless LAN
• each hop is activated by a separate SRS trigger, conveyed in a separate PDCCH.
• the LTE device hops to the next bandwidth part determined by the hopping pattern each time a trigger is received.
• the LTE device sounds the hopping bandwidth based on a single trigger for a multi-shot duration.
• embodiments include a setup procedure as shown at Figure 2 for an LTE FH system in the license-exempt band in which LTE-band (licensed) resources are used to setup the initial FH LTE system configuration and for updating the parameters based on WiFi measurements on the license-exempt bands.
• LTE-band licensed
• WiFi stations conventionally known as non-AP STAs or simply STAs
• the macro eNB would likely interfere more extensively with APs and STAs in its cell range, given its high-powered wide-area DL transmissions and the UL transmissions it receives from mobile devices.
• Another assumption is that the LTE (licensed) band for the PCell and the license-exempt band for the SCell may not be frequency- adjacent to one another, which means that the mobile device with CA capability would need a dual-transceiver chain (i.e. one DL receiver / UL transmitter for the PCell, and one DL receiver / UL transmitter for the SCell).
• the FH channel set size N ⁇ K, where K is the number of WiFi channels in the license exempt band.
• each variable i, j, u, L, N and K are each positive integers.
• PRBs Physical Resource Blocks
• L ⁇ K is the number of FH time intervals per FH pattern
• u indicates the u h FH pattern
• j indicates the h FH time interval within the FH pattern.
• the macro eNB which controls the licensed band (the PCell), may allocate certain transmission opportunities to the HeNB for the DL signaling it is to conduct in the licensed band/PCell as represented by blocks 202 and 204.
• the below examples utilize the more specific term HeNB without loss of generality.
• Cross-carrier scheduling has the advantage of not transmitting Layer 1 (LI) control signaling [which includes the physical control format indicator (PCFICH), the PDCCH, and the physical HARQ indicator channel (PHICH)] in the non-data region of the LTE subframe in the SCell on the license-exempt band. This minimizes interference to WiFi systems there.
• LI Layer 1
• the FH timing interval may be indicated by RRC signaling as sfx, with sfx a multiple of LTE subframes or LTE radio frames.
• the cross-carrier scheduler in the HeNB may schedule DL and UL resources for SCell#z in FH WiFi channel, w;, in all the subframes within the FH time interval, T U*L + ] , or in a subset of subframes, depending on the DL and UL traffic of devices on the SCell.
• the FH channel set W may be activated and/or de-activated and re-configured via RRC signaling within a FH configuration time L*sfx (L multiplied by the FH timing interval).
• the FH resource block H may be scheduled by the HeNB via MAC signaling with a dynamic scheduler. Whilst semi-persistent scheduling can only be used on the PCell in LTE Release 10, in the event it is allowed on an SCell in future releases then scheduling the FH resource block H via the HeNB's MAC signaling can also be realized by semi-persistent scheduling as opposed to only by dynamic scheduling.
• the FH parameters may be optimized by the HeNB based on WiFi measurements by the mobile device on the SCell.
• the FH parameters may be optimized in that:
• h ; 6, 7, .., 110 PRBs assuming LTE system bandwidth of up to 20 MHz can be used in the WiFi channel w;.
• FIGS 3A and 3B give example embodiments of the above FH setup mechanisms, in which each row represents a different licensed-exempt channel w; and each column represents a different FH time interval T u .
• These assume an IEEE WiFi 802.1 1b network in the ISM band in the United States, which has eleven 5 MHz WiFi channel numbers 1-1 1 in the center frequency 2-412 to 2.462 GHz.
• M PRBs
• Figure 3A represents the case in which N (the FH channel set size) is less than K (the number of channels in the license-exempt band).
• L the number of FH time intervals per FH pattern
• the HeNB scheduled FH resource block in WiFi channel w 4 in T3 in the first N FH time intervals and then at reference number 311 scheduled it in ⁇ + in the second K FH time intervals.
• the HeNB scheduled FH resource block 13 ⁇ 4 in WiFi channel w 6 in T5 with more PRBs in the second K FH time intervals than at reference number 321 in ⁇ 6 ⁇ +5 at the first K time intervals.
• the relatively larger number of PRBs is indicated by larger darker shared area, and is an example as noted with respect to Figure 2 of the eNB optimizing the FH by using a larger bandwidth on the SCell in the WiFi channel.
• the number of PRBs (M) allocated to the FH resource blocks hi for SCell#l, SCell#2, SCell#3, SCell#4, and SCell#5 are respectively up to 25 PRBs, 100 PRBs, 50 PRBs, 50 PRBs, and 50 PRBs, since there are up to 25 PRBs per license-exempt channel.
• Data is scheduled on FH resource block set h 2 , h 3 , I14, h 5 ) in respective FH time intervals T l s T 2 , T 3 , T 4 , T 5 as shown at Figure 3B.
• the third (356) and fourth (358) L FH time intervals are similarly illustrated at Figure 3B.
• reference number 360 shows that the HeNB scheduled FH resource block h 2 in WiFi channel w 2 in T 2 in the first L FH time intervals 352, and then as shown by reference number 361 the HeNB scheduled it in T L + 5 in the second L FH time intervals 354 (and further in Ti 3 in the third L FH time intervals 356 and additionally in Tis in the fourth L FH time intervals 358).
• the HeNB can exclude some channels from the FH channel set W so that the number N of channels in the FH channel set is less than the total number of channels K in the license-exempt band.
• reference number 370 shows that the HeNB scheduled FH resource block h 4 in WiFi channel w 4 in T 4 in the first L FH time intervals 352 with more PRBs than reference number 371 in in the second L time intervals 354.
• the larger number of PRBs is represented as a relatively larger area of darkened shading. This shows that a larger LTE bandwidth on an SCell in the WiFi channel may be scheduled, such as if no competing beacons (or only weak beacons) are present in the area or if there is good WiFi link quality as mentioned above with respect to Figure 2.
• Figures 3A-B above only show LTE carriers mapped to WiFi channels on the license-exempt band at 2.4 GHz via FH for simplicity. If we assume LTE frequency division duplex FDD SCell, then a DL SCell CC and a UL SCell CC will need to be mapped to separate WiFi channels. If those license-exempt channels are in the ISM band they will need to be at least 40 MHz apart; if they are in the TVWS band they need only be disjoint (non-contiguous in frequency).
• the ISM band at 5 GHz (802.1 la) has channel numbers
• the TVWS bands are on channels 14-36 (470-608 MHz) and 38-51 (614-698 MHz), which have respective bandwidths of 138 MHz and 84 MHz. This also allows sufficient usable bandwidth and allows a 40 MHz frequency gap between the UL and the DL CCs.
• a frequency gap of about 40 MHz between the PCell CC and the SCell CC will be needed if it is further assume that simultaneous transmission and reception is allowed (i.e. a PCell subframe in the DL direction with a corresponding SCell subframe in the UL direction, or vice versa). This still allows a total usable bandwidth of 55 MHz for the SCell, assuming the PCell is on another (e.g., cellular/licensed) band.
• the FH parameters may be optimized based on measurement reports received from the mobile devices. Since the mobile devices are communicating on a LTE PCell and a WiFi SCell, it is reasonable to assume they are equipped with an LTE modem and a WiFi modem, and that the HeNB is aware that the mobile device has a WiFi modem as indicated during initial LTE cell access via higher layer signaling.
• the WiFi modem may be used to detect WiFi beacon frames transmitted by nearby WiFi Access Points APs. It is also reasonable to assume that both modems may access common memory address space in the mobile device to allow the LTE modem to read WiFi beacon-based measurements.
• the HeNB transmits its almost-blank subframes according to a known pattern and at those times the macro eNB can schedule its user devices which are operating in the area of the HeNB without the user device seeing excessive interference from the HeNB.
• the HeNBs also need to transmit other LI signaling such as the primary/secondary- synchronization channels (P/S-SCH), the broadcast channel (BCCH) and the paging channel (PCH) in the middle six PRBs in the SCells to support standalone SCells with some impact on WiFi, as further analyzed below.
• P/S-SCH primary/secondary- synchronization channels
• BCCH broadcast channel
• PCH paging channel
• One of the ways the HeNB can optimize the FH parameters is by selecting or de-selecting which WiFi channels w; are to be in the WiFi channel set W.
• the HeNB may change the number of WiFi channels w; in the FH channel set pseudo-dynamically by the eNB in two ways:
• the HeNB • explicitly with the HeNB updating the FH channel set W for all the devices configured on SCells (such as if there are multiple devices to detect and report strong beacon signals from a nearby WiFi AP; such reporting to the HeNB can be via RRC signaling, or via MAC signaling of CQI measurement reports adapted for this purpose);
• This WiFi beacon-based approach is a pro-active method in that it allows the eNB to vary the number of PRBs (M) allocated to a FH resource block (hi) for a WiFi channel (w;) based on some detected WiFi beacon signal strength level threshold (e.g., no beacon; weak beacon; and strong beacon ranges).
• M PRBs
• One embodiment to pro-actively reduce that delay is to utilize an LTE-modem in the license-exempt band using either (or some combination of) clear channel assessment/energy detection (CCA/ED) or clear channel assessment/preamble detection (CCA/PD) algorithms.
• CCA/ED can be carried out anywhere within the physical layer convergence protocol (PLCP) frame or for that matter any frame type (control, management, data).
• PLCP physical layer convergence protocol
• CCA/PD algorithms detect the preamble sent at the beginning of the PLCP frame.
• a larger LTE bandwidth may be scheduled on the SCell in the WiFi channel. This may be done by the HeNB changing the value of M, the number of PRBs assigned to a FH resource block hi.
• the value of M PRBs assigned to a FH resource block 13 ⁇ 4 on the SCell in a WiFi channel w; may be scheduled by the HeNB in two main ways in order to allow for optimizing the FH pattern frequency parameters:
• the device can then store the WiFi beacon-based measurements for the WiFi channel w; in a shared local memory within the device, from which the device's LTE modem can access in order to report the measurements to the HeNB.
• the Ack/Nack approach above is more reactive in that it is based on ACK/NACK messages corresponding to the past transmissions on the specific frequencies.
• the HeNB can vary the number of PRBs (M) allocated to a FH resource block (hi) for a WiFi channel (w;) based on some Ack/Nack rate threshold (e.g., poor channel quality; average channel quality; and good channel quality).
• M PRBs
• w FH resource block
• some Ack/Nack rate threshold e.g., poor channel quality; average channel quality; and good channel quality.
• the Ack/Nack approach is faster since it does not require WiFi measurement reports and hence avoids the WiFi measurement delay that is quantified above.
• the Ack/Nack technique requires use of the WiFi modem only in the device, which saves battery power since the WiFi modem will only be needed during initial setup of the SCell on the license-exempt band for discovery of any neighboring WiFi APs.
• the HeNB configures the mobile devices for the SCell(s) in the license-exempt band through the use of PCell resources, which can also be used to activate frequency hopping as in the examples above.
• the LTE devices are attached to the PCell on the LTE (licensed) band and so R C signaling by the HeNB to the UE on the PCell can be used to configure: component carriers for SCells and cross scheduler parameters; FH parameter configurations for the SCells; and activation of cross-carrier scheduling to begin the frequency hopping.
• Figure 4 is a schematic diagram of cross scheduling which illustrates how resources on the SCell are allocated from the PCell.
• SCell-specific search spaces SS
• the mobile devices receive on the PCell from the HeNB their DL and UL grants for resources which lie on the SCells via the PDCCH addressed to specific mobile devices which they find in their SCell-specific search space.
• LI signaling will also be used for synchronization, for system information, and for paging on the license-exempt band.
• the HeNBs may need to transmit other LI signaling such as primary and secondary synchronization channel (P/S-SCH), broadcast channel (BCCH) and paging channel (PCH) in the middle six PRBs in the Scells in order to support standalone SCells; that is, to support mobile LTE devices which have the capability to operate in CA but not with extension carriers (CCs without a control channel region and which carry data channels only).
• Extension CCs are distinguished from standalone CCs below with reference to Figure 5.
• the LTE transmission power in the mid six PRBs in the license-exempt band (i.e. TVWS band or ISM band) must be within the regulated transmission power to avoid interfering with WiFi transmissions by other devices. Since the transmission of eNB LI signaling over the middle six PRBs is over a relatively small bandwidth (i.e. 6 PRBs span about 1 MHz), it is not likely to cause significant interference on the WiFi channels which use a relatively larger system bandwidth (i.e. 22 MHz for 802.1 lb and 20 MHz for 802.1 la).
• Such LI signaling might be avoided by releasing the RRC connection or by using an extension carrier, but these are seen to be less desirable than retaining the LI signaling.
• the RRC Connection can be released for all devices such as when there is a "busy" WiFi cell as detected by the device measurements on the SCell. But this would release the established radio bearers as well as all radio resources and assuming (reasonably) that there may be many APs within the SCell coverage area, all SCell CCs on "busy” WiFi channels will have to be released.
• Figure 5 illustrates the distinction between a standalone and an extension CC.
• the extension CC only contains data as illustrated there, due to synchronization requirements assuming a non-adjacent (or large) LTE band for the PCell and license-exempt band for the SCell.
• the standalone carrier does have a control channel region 502 and so can carry the primary broadcast channel PBCH 504 and synchronization (P-SCH/S-SCH) 506.
• the standalone CC can support mobility using its own control channel region 502 and can send common reference signals CRSs to the mobile devices, whereas mobility on the extension carrier must lie in another CC and no CRSs are exchanged in an extension carrier. This means that Release 8/9/10 devices without a CA capability can be supported on the license-exempt bands if the SCell is a standalone CC but not if the SCell were an extension carrier.
• the HeNB can pseudo-dynamically adapt the FH time and frequency parameters (explicitly or implicitly as detailed above with respect to block 206 of Figure 2).
• the HeNB may configure new blank DL subframes on the SCell to devices via RRC signaling (i.e., the HeNB stops transmitting data or signaling) so as to allow WiFi beacon-based measurements by the WiFi modem in the user device without interference from the HeNB's own transmissions.
• bladenk subframes may be considered as a coordinated silencing between (macro and micro) eNB transmissions as an inter-cell interference management technique relying on Time-Division Multiplexing (TDM) of physical (PHY) channels or signals from different cells.
• TDM Time-Division Multiplexing
• PHY physical channels or signals from different cells.
• interference from the HeNB's middle six PRB transmissions may only partially interfere with a fraction of the WiFi measurements in the frequency domain. In this case it may be that the remainder of the WiFi signal is sufficient for the device to compile a measurement report which is comprehensive enough for the HeNB to properly adapt its FH parameters.
• the HeNB does not schedule any UL grant for the SCell which would create a measurement gap for the WiFi measurements in the SCell UL subframe on the license-exempt band. So in this case only the HeNB needs to take this into account when allocating to the device their UL and DL resources and there is no specific action the UE needs to do to avoid a measurement gap.
• the interference from the LTE system to the WiFi system on license-exempt shared bands can be minimized or otherwise mitigated via frequency agility/frequency hopping. It is also a distinct advantage that resources are flexibly allocated to devices on the license-exempt (shared) band via cross-carrier scheduling, based on user device WiFi measurements in that shared band.
• a method or an apparatus comprising a processing system, for example having at least one processor and a memory storing a set of computer instructions, which are configured to cause the apparatus to do the following.
• the frequency hopping resource block 13 ⁇ 4 contains M physical resource blocks PRBs, scheduled for the (at least one) secondary cell SCell during a frequency hopping time interval T M*L+ / by a downlink resource grant and an uplink resource grant sent on a physical downlink control channel PDCCH of the primary cell PCell, in which M is an integer at least equal to one, u identifies one pattern for the frequency hopping, and j indicates a h frequency hopping time interval within the pattern.
• the R C signaling to configure the N secondary cells on the license-exempt channels/license exempt band is sent by a HeNB (or more generally a micro access node) on the primary cell PCell, the cross carrier scheduling is also sent by the HeNB on the primary cell PCell, and the primary cell PCell lies within a licensed frequency band.
• each SCell occupies only one of the license-exempt channels w,; and for the case that N ⁇ K, at least one SCell occupies more than one of the license-exempt channels w;.
• the RRC signaling further comprises an indication of a frequency hopping time interval T which is an integer multiple of subframes or radio frames used in the primary cell PCell.
• the measurements of at least some of the license-exempt channels w; received from at least the user device comprise measurement reports received via radio resource control signaling, and the parameters for the frequency hopping are adapted by changing a number M of PRBs allocated to an z 'th FH resource block 13 ⁇ 4 based on whether the received measurement reports indicate a weak beacon, a strong beacon, or no beacon.
• the measurements of at least some of the license-exempt channels w; received from at least the user device comprise acknowledgements/negative acknowledgements received via at least some of the license-exempt channels w3 ⁇ 4 and the parameters for the frequency hopping are adapted by changing a number M of PRBs allocated to an z 'th FH resource block 13 ⁇ 4 based on whether a rate of the received acknowledgements/negative acknowledgements indicate poor channel quality, good channel quality or average channel quality.
• This is detailed above as useful for the case that the user device reports a strong beacon on an z 'th license-exempt channel w;.
• a macro eNB 22 is adapted for communication over a licensed-band wireless link 21 with an apparatus, such as a mobile terminal or UE 20. While the examples above were in the context of the LTE-A system, the eNB 22 may be any access node (including frequency selective repeaters) of any wireless network such as LTE, LTE-A, GSM, GERAN, 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 or radio network controller RNC which provides connectivity with further networks (e.g., a publicly switched telephone network PSTN and/or a data communications network/Internet).
• a network control element such as a mobility management entity MME and/or serving gateway SGW 24 or radio network controller RNC which provides connectivity with further networks (e.g., a publicly switched telephone network PSTN and/or a data communications network/Internet).
• a network control element such as a mobility management entity MME and/or serving gateway SGW 24 or radio network controller RNC which provides connectivity with further networks (e.g., a publicly switched telephone network PSTN and/or a data communications network/Internet).
• PSTN Public Switchet Control Network
• RNC radio network controller
• the UL traffic from the UE 20 is similarly offloaded to the license-exempt band and the UE sends this UL traffic to the HeNB 26 on the license-exempt band rather than to the macro eNB 22 on the LTE licensed band. It is the HeNB 26 which configures for the UE 20 the SCells, and which sends to the UE 20 on the (licensed band) PCell the cross scheduled (license-exempt band) SCell resources.
• this UL traffic may or may not pass also from the HeNB 26 to the macro eNB 22 depending on the HeNB's other network connections and/or the destination of that traffic, and/or it is possible that some of the offloaded DL traffic may be ported directly to the HeNB 26 without first passing through the macro eNB 22.
• the UE 20 includes processing means such as at least one data processor
• DP storing means such as at least one computer-readable memory (MEM) 20B storing at least one computer program (PROG) 20C or other set of executable instructions, communicating means such as a transmitter TX 20D and a receiver PvX 20E for bidirectional wireless communications with the eNodeB 22 via one or more antennas 20F.
• MEM computer-readable memory
• PROG computer program
• communicating means such as a transmitter TX 20D and a receiver PvX 20E for bidirectional wireless communications with the eNodeB 22 via one or more antennas 20F.
• TX 20D and RX 20E are shown for clarity of illustration.
• 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 storing 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 its offload to Home eNB rules/procedures if such offload is implemented in LTE network, and possibly also the macro eNB 22 may track at leave the traffic volume which is being offloaded so it may continue or discontinue traffic offloading as detailed herein as network conditions on the licensed band changes.
• the HeNB 26 Similar to the eNB 22 but typically operating at a much reduced transmit power level (e.g., up to 2 watts for a HeNB versus a low of about 5 watts for a macro eNB), the HeNB 26 also includes processing means such as at least one data processor (DP) 26A, storing means such as at least one computer-readable memory (MEM) 26B storing at least one computer program (PROG) 26C or other set of executable instructions, and communicating means such as a transmitter TX 26D and a receiver RX 26E for bidirectional wireless communications on license-exempt channels with the UE 20 via one or more antennas 26F.
• processing means such as at least one data processor (DP) 26A
• MEM computer-readable memory
• PROG computer program
• the HeNB 26 carries out SCell setup rules/procedures as detailed above and the cross scheduling rules for cross scheduling on the license-exempt SCell from the licensed PCell as variously described in the embodiments above. There is also a control and data link 25 between the eNB 22 and the MME/S-GW 24, and there may be an additional control link 27 between the eNB 22 and the HeNB 26.
• 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 22, 26 and which also operates utilizing the cross-scheduling rules according to these teachings.
• 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 embodiments, as detailed above.
• the eNB 22 and the HeNB 26 also have software stored in their respective MEMs 22B, 26B to implement certain aspects of these teachings.
• Embodiments may be implemented at least in part by computer software stored on the MEM 20B, 22B, 26B which is executable by the DP 20A of the UE 20 and/or by the DP 22A, 26A of the eNB 22 and HeNB 26 respectively, or by hardware, or by a combination of tangibly stored software and hardware (and tangibly stored firmware).
• Electronic devices implementing these aspects 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.
• 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.
• Various embodiments of the computer readable MEMs 20B, 22B, 26B 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, 26 A include but are not limited to general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and multi-core processors.

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• 2012
  • 2012-06-01 CN CN201280035829.4A patent/CN103875187B/zh not_active Expired - Fee Related
  • 2012-06-01 WO PCT/IB2012/052764 patent/WO2012164531A1/en active Application Filing
  • 2012-06-01 EP EP12737346.2A patent/EP2715948A1/en not_active Withdrawn

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