Patent Description:
The present specification generally relates to the field of narrowband internet of things technology. NB-loT is a leading technology in the internet of things (IoT) domain). NB-loT was defined in <NUM>rd Generation Partnership Project (3GPP) specification Rel-<NUM>, but details are still being worked on. A number of compromises were made during the specification time, and detailed studies of more optimal solutions were not effected in any case.

Here, in relation to the present invention, user equipment (UE) measurement requirements have been standardized for NB-loT. It was discussed whether an NB-loT synchronization signal (narrowband internet of things secondary synchronization signal (NSSS, also NB-SSS)) could be used by the UE when performing measurements of e.g. narrowband internet of things reference signal received power (NRSRP) and narrowband internet of things reference signal received quality (NRSRQ). The power level of the NSSS was not verified, and thus, the power level was not guaranteed in a similar manner as for the narrowband internet of things reference signal (NRS, also NB-RS). Accordingly, the NSSS could not be used for UE measurements.

Hence, measurements based on the NRS became necessary.

Accordingly, NRSRP and NRSRQ measurement requirements were developed based on a worst case scenario which is inband NB-loT deployment. In this regard, it is noted that the NB-loT operation mode may be one of inband mode, guard-band mode, and stand-alone mode. Inband (also in-band) means utilizing resource blocks within a normal (Long Term Evolution (LTE)) carrier. Guard-band means utilizing resource blocks within a (LTE) carrier's guard-band. Standalone (also stand-alone) means utilizing resource blocks within dedicated spectrum.

Reason for this approach (measurement requirements developed based on worst case scenario "inband") was that UE would only know the NB-IoT operation mode (inband, guard-band and stand-alone) for the (its) serving cell, while neighbor cell operation mode would not be known, unless UE would read the master information block (MIB) of the neighbor cell. Reading MIB from neighbor cells in NB-IoT is not realistic option in practice simply due to delays especially when operating on challenging cell edge conditions. Besides, neighbor cell MIB reading would complicate UE implementation and increase the UE battery consumption.

<FIG> is an illustration of NB-RS, NB-SSS, and narrowband internet of things primary synchronization signal (NPSS, also NB-PSS) in an inband NB-loT scenario when the UE does not have information on valid downlink (DL) subframes.

Before the UE has knowledge about neighbor cells' valid configuration of the cell-specific valid DL subframes, it may assume that NB-RS is transmitted in subframes #<NUM> and #<NUM> and in subframe #<NUM> if it does not contain NB-SSS.

<FIG> is an illustration of NB-RS, NB-SSS, and NB-PSS in a stand-alone NB-loT scenario, when the UE has knowledge of valid and invalid DL subframes.

Hence, the problem arises that in the worst case scenario (inband mode is assumed), the UE may use less opportunities to measure the reference signal (NB-RS) than are actually provided, and thus, the NB-loT system performance is not optimal.

Hence, there is a need to provide for measurement mode determination for NB-loT devices.

In other words, there is a need to significantly improve the NB-IoT system performance in general, and in particular, to indicate neighbor carrier/cells operation mode to enable knowledge about neighbor cells valid configuration of the cell-specific valid DL subframes. Prior art which relates to this field can be found in document <CIT>, disclosing a communications device, an infrastructure equipment, a wireless communications network, and respective methods. The communications device is configured to transmit signals to and/or receive signals from the infrastructure equipment of the mobile communications network. The communications device comprises a receiver, a transmitter and a controller. The receiver is configured to receive signals transmitted by the infrastructure equipment, the transmitter is configured to transmit signals to the infrastructure equipment, and the controller is configured to control the transmitter and the receiver to receive data from the infrastructure equipment. The wireless access interface is provided by the mobile communications network within a system bandwidth, and the transmitter and the receiver are configured to transmit and receive signals within a bandwidth which is narrower than the system bandwidth using predetermined narrowband carriers of different types. The communications device is configured to receive from the mobile communications network an indication listing narrowband carriers provided by one or more infrastructure equipment forming one or more cells of the mobile communications network, and an indication of the type of the narrowband carriers. The communications device is configured to measure a strength of signals received from each of the narrowband carriers, to select one of the narrowband carriers from the list of the narrowband carriers based on the type of the narrowband carrier and a value of the measured strength of the signals received from the narrowband carriers, and to transmit signals to the infrastructure equipment providing the selected narrowband carrier to inform the mobile communications network that the communications device can receive data from the mobile communications network via the selected narrowband carrier, from the narrowband carriers or all types, so that an uplink transmission power can be reduced. Accordingly, the communications device can bias a selection or reselection to a preferred narrowband carrier type depending on a strength of signals received.

Further prior art can be found in document <CIT>, disclosing systems and methods for using neighboring cell information to perform measurements. A method in a wireless device in a first cell includes receiving, from a first network node in the first cell, assistance information related to at least one of an operation mode and a subframe configuration associated with a second cell that neighbors the first cell. Based on the assistance information, a plurality of measurement subframes are determined and measurements are performed using the plurality of measurement subframes.

Still further prior art can be found in document '<NPL>', in document '<NPL>, and in document '<NPL>'.

The present invention aims at addressing at least part of the above issues and/or problems and drawbacks.

The invention is defined in the appended independent claims. Advantageous modifications thereof are set forth in the appended dependent claims.

Any one of the above aspects enables an efficient improvement for NB-IoT in terms of improving the UE performance and thereby also the overall performance of the NB-IoT to thereby solve at least part of the problems and drawbacks identified in relation to the prior art.

By way of exemplary embodiments of the present invention, there is provided measurement mode determination for NB-IoT devices. More specifically, by way of exemplary embodiments of the present invention, there are provided measures and mechanisms for realizing measurement mode determination for NB-loT devices.

Thus, improvement is achieved by methods, apparatuses and computer program products enabling/realizing measurement mode determination for NB-loT devices.

In the following, the present invention will be described in greater detail by way of non-limiting examples with reference to the accompanying drawings, in which.

The present invention is described herein with reference to particular non-limiting examples and to what are presently considered to be conceivable embodiments of the present invention. A person skilled in the art will appreciate that the invention is by no means limited to these examples, and may be more broadly applied.

It is to be noted that the following description of the present invention and its embodiments mainly refers to specifications being used as non-limiting examples for certain exemplary network configurations and deployments. Namely, the present invention and its embodiments are mainly described in relation to 3GPP specifications being used as non-limiting examples for certain exemplary network configurations and deployments. In particular, a narrowband internet of things scenario is used as a non-limiting example for the applicability of thus described exemplary embodiments. As such, the description of exemplary embodiments given herein specifically refers to terminology which is directly related thereto. Such terminology is only used in the context of the presented non-limiting examples, and does naturally not limit the invention in any way. Rather, any other communication or communication related system deployment, etc. may also be utilized as long as compliant with the features described herein.

Here, it is noted that the following present provisions in relation to NB-loT are considered.

Namely, current UE measurement core requirements and performance are listed in 3GPP TS <NUM>. All core and performance requirements are developed based on inband operation. Based on the simulations the following was specified.

For NB-loT intra frequency measurements under normal coverage, when no discontinuous reception (DRX) is used, in the RRC_CONNECTED state the measurement period for intra frequency measurements is <NUM>. The NRSRP measurement accuracy shall be specified as cited below.

For NB-IoT intra frequency measurements under normal coverage, when DRX is used, in the RRC_CONNECTED state the measurement period for intra frequency measurements is Tmeasure_intra as shown in the table below, reflecting requirements for intrafrequency measurement.

The NRSRP measurement accuracy shall be specified as cited below.

For NB-loT intra frequency measurements under enhanced coverage, when no DRX is used, in the RRC_CONNECTED state the measurement period for intra frequency measurements is <NUM>. The NRSRP measurement accuracy shall be specified as cited below.

For NB-IoT intra frequency measurements under enhanced coverage, when DRX is used, in the RRC_CONNECTED state the measurement period for intra frequency measurements is Tmeasure_intra as shown in the table below, reflecting requirements for intrafrequency measurement.

The above-referenced measurement accuracy is addressed below, where the accuracy requirements are exemplarily defined.

In particular, for intra-frequency absolute NRSRP accuracy for UE category NB1, the requirements apply to a cell on the same frequency as that of the serving cell for UE category NB1 for stand-alone, guard-band and inband deployments.

The accuracy requirements in the table below illustrating NRSRP intra frequency absolute accuracy for UE category NB1 for half-duplex frequency division duplexing (HD-FDD) are valid under the following conditions:.

As is derivable from this table, the accuracy requirements are very relaxed for NB-loT devices in ≥-<NUM>Ês/Iot ≥-<NUM> dB conditions.

Hereinafter, various embodiments and implementations of the present invention and its aspects or embodiments are described using several variants and/or alternatives. It is generally noted that, according to certain needs and constraints, all of the described variants and/or alternatives may be provided alone or in any conceivable combination (also including combinations of individual features of the various variants and/or alternatives).

According to exemplary embodiments of the present invention, in general terms, there are provided measures and mechanisms for (enabling/realizing) measurement mode determination for NB-IoTdevices.

<FIG> is a block diagram illustrating an apparatus according to exemplary embodiments of the present invention. The apparatus may be a terminal <NUM> such as an loT UE comprising a receiving circuitry <NUM>, a deriving circuitry <NUM>, and a measuring circuitry <NUM>. The receiving circuitry <NUM> receives configuration information indicative of a measurement mode in relation to a neighbor cell. The deriving circuitry <NUM> derives said measurement mode of said neighbor cell from said configuration information. The measuring circuitry <NUM> measures a reference signal of said neighbor cell based on said measurement mode. Here, said configuration information includes information indicating a measurement mode used on said neighbor cell. Alternatively, said configuration information includes information indicating measurement modes not used on said neighbor cell, wherein the apparatus further comprises a deducing circuitry <NUM> configured to deduce a measuring mode not indicated as being not used on said neighbor cell as said measurement mode of said neighbor cell. <FIG> is a schematic diagram of a procedure according to exemplary embodiments of the present invention. The apparatus according to <FIG> may perform the method of <FIG> but is not limited to this method. The method of <FIG> may be performed by the apparatus of <FIG> but is not limited to being performed by this apparatus.

As shown in <FIG>, a procedure according to exemplary embodiments of the present invention comprises an operation of receiving (S41) configuration information indicative of a measurement mode in relation to a neighbor cell, an operation of deriving (S42) said measurement mode of said neighbor cell from said configuration information, and an operation of measuring (S43) a reference signal of said neighbor cell based on said measurement mode. Here, said configuration information includes information indicating a measurement mode used on said neighbor cell. Alternatively, said configuration information includes information indicating measurement modes not used on said neighbor cell, and the deriving operation (S42) comprises an operation of deducing a measuring mode not indicated as being not used on said neighbor cell as said measurement mode of said neighbor cell.

<FIG> is a block diagram illustrating an apparatus according to exemplary embodiments of the present invention. In particular, <FIG> illustrates a variation of the apparatus shown in <FIG>. The apparatus according to <FIG> may thus further comprise assuming circuitry <NUM>, inferring circuitry <NUM>, adopting circuitry <NUM>, reading circuitry <NUM>, determining circuitry <NUM>, performing circuitry <NUM>, and/or selecting circuitry <NUM>.

In an embodiment at least some of the functionalities of the apparatus shown in <FIG> (and <FIG>) may be shared between two physically separate devices forming one operational entity. Therefore, the apparatus may be seen to depict the operational entity comprising one or more physically separate devices for executing at least some of the described processes.

According to exemplary embodiments of the present invention, said measurement mode of said neighbor cell is a measurement mode related to one of an inband operation mode of said neighbor cell, a guard-band operation mode of said neighbor cell, and a stand-alone operation mode of said neighbor cell.

According to a variation of the procedure shown in <FIG>, exemplary details of the measuring operation (S43) are given, which are inherently independent from each other as such.

Such exemplary measuring operation (S43) according to exemplary embodiments of the present invention may (without said measurement mode of said neighbor cell being derived) comprise an operation of assuming transmission of said reference signal in downlink subframes <NUM> and <NUM> and, if a predetermined synchronization signal is not transmitted in downlink subframe <NUM>, in said downlink subframe <NUM>.

Further, according to exemplary embodiments of the present invention, said configuration information is indicative of presence and/or absence of restriction of said downlink subframes, and in case of indicated absence of restriction of said downlink subframes, such exemplary measuring operation (S43) according to exemplary embodiments of the present invention may (without said measurement mode of said neighbor cell being derived) comprise an operation of assuming transmission of said reference signal in downlink subframes <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>, and, if said predetermined synchronization signal is not transmitted in said downlink subframe <NUM>, in said downlink subframe <NUM>.

According to further exemplary embodiments of the present invention, said configuration information is indicative of a measurement mode used on said neighbor cell.

According to a variation of the procedure shown in <FIG>, exemplary details of the deriving operation (S42) are given, which are inherently independent from each other as such.

Namely, according to exemplary embodiments of the present invention, said configuration information is indicative of a measurement mode used on a carrier, and such exemplary deriving operation (S42) according to exemplary embodiments of the present invention may comprise an operation of inferring, as said measurement mode of said neighbor cell, said measurement mode used on said carrier related to said neighbor cell.

Further, according to exemplary embodiments of the present invention, said configuration information is indicative of a measurement mode used on a public land mobile network, and such exemplary deriving operation (S42) according to exemplary embodiments of the present invention may comprise an operation of inferring, as said measurement mode of said neighbor cell, said measurement mode used on said public land mobile network related to said neighbor cell.

Further, according to exemplary embodiments of the present invention, said configuration information is indicative of a measurement mode used on a frequency, and such exemplary deriving operation (S42) according to exemplary embodiments of the present invention may comprise an operation of inferring, as said measurement mode of said neighbor cell, said measurement mode used on said frequency related to said neighbor cell.

Further, according to exemplary embodiments of the present invention, said configuration information is indicative of said measurement mode in relation to said neighbor cell with reference to a measurement mode used on a present cell.

According to still further exemplary embodiments of the present invention, said reference is indicative of one of that said measurement mode in relation to said neighbor cell is the same as said measurement mode used on said present cell, and that said measurement mode in relation to said neighbor cell is the different from said measurement mode used on said present cell.

According to a still further variation of the procedure shown in <FIG>, exemplary details of the deriving operation (S42) are given, which are inherently independent from each other as such.

Namely, according to exemplary embodiments of the present invention, said configuration information is indicative of that the same measurement mode is applied on all cells, and such exemplary deriving operation (S42) according to exemplary embodiments of the present invention may comprise an operation of adopting, as said measurement mode of said neighbor cell, a measurement mode used on a present cell.

Further, according to exemplary embodiments of the present invention, said configuration information is indicative of that said measurement mode used on said present cell is to be adopted as said measurement mode of said neighbor cell, and such exemplary deriving operation (S42) according to exemplary embodiments of the present invention may comprise an operation of adopting, as said measurement mode of said neighbor cell, a measurement mode used on a present cell.

Further, according to exemplary embodiments of the present invention, said configuration information is indicative of that the same measurement mode is not applied on all cells, and such exemplary deriving operation (S42) according to exemplary embodiments of the present invention may comprise an operation of reading said measurement mode of said neighbor cell from a master information block of said neighbor cell.

Further, according to exemplary embodiments of the present invention, said configuration information is indicative of that said measurement mode of said neighbor cell is to be read from a master information block of said neighbor cell, and such exemplary deriving operation (S42) according to exemplary embodiments of the present invention may comprise an operation of reading said measurement mode of said neighbor cell from a master information block of said neighbor cell.

According to a still further variation of the procedure shown in <FIG>, exemplary details of the measuring operation (S43) are given, which are inherently independent from each other as such.

Such exemplary measuring operation (S43) according to exemplary embodiments of the present invention may comprise an operation of determining downlink subframes for said measuring, and an operation of performing radio measurement of a reference signal in said subframes for said measuring.

<FIG> is a block diagram illustrating an apparatus according to exemplary embodiments of the present invention. The apparatus may be a network node <NUM> such as an IoT related network sided controlling entity comprising a determining circuitry <NUM> and a transmitting circuitry <NUM>. The determining circuitry <NUM> determines a measurement mode of a neighbor cell of a served terminal. Said transmitting circuitry <NUM> transmits configuration information indicative of said measurement mode of said neighbor cell. Here, said configuration information is indicative of said measurement mode in relation to said neighbor cell with reference to a measurement mode used on a present cell serving said terminal. <FIG> is a schematic diagram of a procedure according to exemplary embodiments of the present invention. The apparatus according to <FIG> may perform the method of <FIG> but is not limited to this method. The method of <FIG> may be performed by the apparatus of <FIG> but is not limited to being performed by this apparatus.

As shown in <FIG>, a procedure according to exemplary embodiments of the present invention comprises an operation of determining (S51) a measurement mode of a neighbor cell of a served terminal, and an operation of transmitting (S52) configuration information indicative of said measurement mode of said neighbor cell. Here, said configuration information is indicative of said measurement mode in relation to said neighbor cell with reference to a measurement mode used on a present cell serving said terminal.

In an embodiment at least some of the functionalities of the apparatus shown in <FIG> may be shared between two physically separate devices forming one operational entity. Therefore, the apparatus may be seen to depict the operational entity comprising one or more physically separate devices for executing at least some of the described processes.

According to further exemplary embodiments of the present invention, said configuration information is indicative of a measurement mode used on said neighbor cell, and/or said configuration information is indicative of a measurement mode used on a carrier, and/or said configuration information is indicative of a measurement mode used on a public land mobile network, and/or said configuration information is indicative of a measurement mode used on a frequency.

According to still further exemplary embodiments of the present invention, said configuration information includes information indicating a measurement mode used on said neighbor cell, and/or said configuration information includes information indicating measurement modes not used on said neighbor cell.

According to still further exemplary embodiments of the present invention, said configuration information is indicative of that the same measurement mode is deployed on all cells, and/or said configuration information is indicative of that said measurement mode used on said present cell is to be adopted as said measurement mode of said neighbor cell, and/or said configuration information is indicative of that the same measurement mode is not deployed on all cells, and/or said configuration information is indicative of that said measurement mode of said neighbor cell is to be read from a master information block of said neighbor cell.

Below, exemplary embodiments of the present invention are described in more specific terms.

Namely, according to exemplary embodiments of the present invention, the UE may be informed about the measurement/operation mode of neighbor cells (serving carrier and/or inter-frequency carrier) using dedicated and/or broadcast signaling.

Likely, according to further exemplary embodiments of the present invention, the NB-IoT operation mode of the carrier could apply to all cells on the carrier and therefore the measurement operation mode could be given on a per carrier basis (alternatively on a per cell basis or on a per public land mobile network (PLMN) basis or on a per frequency basis).

One alternative is that the measurement mode would be configured using the measurement configuration in and given per carrier frequency. The indication of the measurement mode of cells a on a carrier would e.g. be in form of a two bit indication which would allow for indication of the three needed measurement modes:.

It is to be understood that the two-bit coding shown above is merely an example, and this aspect of the present invention is not limited to such implementation.

Another alternative is using a relative indication, e.g., indicating that the measurement object (inter-frequency carrier) is to be measured with the same or a different measurement assumption/mode as the current serving carrier.

According to exemplary embodiments of the present invention, different signaling alternatives are classified in an explicit approach and an implicit approach.

According to exemplary embodiments of the present invention, any combination of the above-mentioned alternatives and variants may be implemented.

The above-mentioned measurement mode may also include/cover information regarding whether the network indicates to the UE that there are or are no restriction on the DL subframes, and/or whether the UE can assume during performing measurements that there are or are no restriction on the DL subframes.

According to exemplary embodiments of the present invention, as outlined above, the indication of the measurement mode of neighbor cells on a carrier is preferably configured to the UE in the measurement configuration. This could be done by a two-bit or one-bit indication.

Based on the measurement mode, the UE measures accordingly, i.e. UE would be able to make full use of the available NRS on the neighbor cell due to the corresponding knowledge of the relevant DL subframes.

According to exemplary embodiments of the present invention, the UE may be required to make use of (all) available NRS based on the new measurement mode indication, and the UE accuracy and performance requirements would be developed based on this.

From system level point of view, this would mean that the UE would be required to make full use of available NRS for measurements and the performance would not be restricted to worst case inband operation.

Hence, implementation if exemplary embodiments of the present invention leads to significantly better UE performance when NB-loT is non-inband operation mode (i.e. guard-band, standalone) and it would be possible to get significantly better UE accuracy requirements than currently possible.

In the foregoing exemplary description of the network entity, only the units that are relevant for understanding the principles of the invention have been described using functional blocks. The network entity may comprise further units that are necessary for its respective operation. However, a description of these units is omitted in this specification. The arrangement of the functional blocks of the devices is not construed to limit the invention, and the functions may be performed by one block or further split into sub-blocks.

In <FIG>, an alternative illustration of apparatuses according to exemplary embodiments of the present invention is depicted. As indicated in <FIG>, according to exemplary embodiments of the present invention, the apparatus (terminal) <NUM>' (corresponding to the terminal <NUM>) comprises a processor <NUM>, a memory <NUM> and an interface <NUM>, which are connected by a bus <NUM> or the like. Further, according to exemplary embodiments of the present invention, the apparatus (network node) <NUM>' (corresponding to the network node <NUM>) comprises a processor <NUM>, a memory <NUM> and an interface <NUM>, which are connected by a bus <NUM> or the like, and the apparatuses may be connected via link <NUM>, respectively.

The processor <NUM>/<NUM> and/or the interface <NUM>/<NUM> may also include a modem or the like to facilitate communication over a (hardwire or wireless) link, respectively. The interface <NUM>/<NUM> may include a suitable transceiver coupled to one or more antennas or communication means for (hardwire or wireless) communications with the linked or connected device(s), respectively. The interface <NUM>/<NUM> is generally configured to communicate with at least one other apparatus, i.e. the interface thereof.

The memory <NUM>/<NUM> may store respective programs assumed to include program instructions or computer program code that, when executed by the respective processor, enables the respective electronic device or apparatus to operate in accordance with the exemplary embodiments of the present invention.

According to exemplary embodiments of the present invention, an apparatus representing the terminal <NUM> comprises at least one processor <NUM>, at least one memory <NUM> including computer program code, and at least one interface <NUM> configured for communication with at least another apparatus. The processor (i.e. the at least one processor <NUM>, with the at least one memory <NUM> and the computer program code) is configured to perform receiving configuration information indicative of a measurement mode in relation to a neighbor cell (thus the apparatus comprising corresponding means for receiving), to perform deriving said measurement mode of said neighbor cell from said configuration information (thus the apparatus comprising corresponding means for deriving), and to perform measuring a reference signal of said neighbor cell based on said measurement mode (thus the apparatus comprising corresponding means for measuring).

According to further exemplary embodiments of the present invention, an apparatus representing the network node <NUM> comprises at least one processor <NUM>, at least one memory <NUM> including computer program code, and at least one interface <NUM> configured for communication with at least another apparatus. The processor (i.e. the at least one processor <NUM>, with the at least one memory <NUM> and the computer program code) is configured to perform determining a measurement mode of a neighbor cell of a served terminal (thus the apparatus comprising corresponding means for determining), and to perform transmitting configuration information indicative of said measurement mode of said neighbor cell (thus the apparatus comprising corresponding means for transmitting).

For the purpose of the present invention as described herein above, it should be noted that.

Generally, any method step is suitable to be implemented as software or by hardware without changing the idea of the present invention. Devices and means can be implemented as individual devices, but this does not exclude that they are implemented in a distributed fashion throughout the system, as long as the functionality of the device is preserved. Such and similar principles are to be considered as known to a skilled person.

The present invention also covers any conceivable combination of method steps and operations described above, and any conceivable combination of nodes, apparatuses, modules or elements described above, as long as the above-described concepts of methodology and structural arrangement are applicable.

In view of the above, there are provided measures for measurement mode determination for NB-loT devices. Such measures exemplarily comprise receiving configuration information indicative of a measurement mode in relation to a neighbor cell, deriving said measurement mode of said neighbor cell from said configuration information, and measuring a reference signal of said neighbor cell based on said measurement mode.

Claim 1:
A method, of a narrowband internet of things device (<NUM>), for determination of measurement modes of narrowband internet of things devices being one of an inband mode, a guard-band mode, and a stand-alone mode, the method comprising
receiving (S41), from a network node being an internet of things related network sided controlling entity (<NUM>), configuration information indicative of a measurement mode of a neighbor cell,
deriving (S42) said measurement mode of said neighbor cell from said configuration information, and
measuring (S43) a reference signal of said neighbor cell based on said measurement mode, wherein
said configuration information includes information indicating measurement modes not used on said neighbor cell, and in relation to said deriving (S42), said method further comprises deducing a measuring mode not indicated as being not used on said neighbor cell as said measurement mode of said neighbor cell.