Patent Description:
In wireless communications systems, one or more UE and one or more base stations may transmit and receive signals between one another. In some cases, the UE may not be used for a period of time and may enter an idle mode and/or a discontinuous reception (DRx) mode to conserve power at the UE. Even though the UE may be in a DRx mode, the base station may transmit a paging message. Due to the directional nature of communicating in mobile networks, the base station may transmit the paging message as a directional beam-based transmission as opposed to an omnidirectional paging broadcast. In some examples, UEs may communicate with anchor or primary carriers and non-anchor or secondary carriers. The UE may be configured to receive paging information on the NB physical downlink control channel (NPDCCH) from a non-anchor paging carrier. In some examples, the paging message may not be present, thus the NB reference signal (NRS) may not be received, especially when the UE is in a discontinuous receive (DRx) cycle. Unfortunately, the absence of the NRS may lead to the inability of the UE to determine the quality of the paging carrier.

A method for detecting poor conditions and reduced quality of the paging carrier may therefore be desirable.

<CIT> relates to methods for transmitting or receiving downlink control and an apparatus. <CIT> relates to a method for performing radio resource management measurements. <NPL>" discusses UE power reduction in RRM measurements for Idle states and Connected state.

In accordance with the present invention, there is provided a method for wireless communications at a user equipment, UE, as set out in claim <NUM>, an apparatus as set out in claim <NUM> and a non-transitory computer-readable medium as set out in claim <NUM>. Other aspects of the invention can be found in the dependent claims. The described techniques relate to improved methods, systems, devices, and apparatuses that support measurements for NB IoT devices. The described techniques provide for using cell-specific reference signals (CRS) to measure various quality parameters of the paging carrier. In some examples, a NB reference signal may also be received and may be used to measure various quality parameters. In some examples, the CRS and the NRS measurements may be combined and used to determine whether early termination of the paging occasion is appropriate to conserve power at the UE.

In some examples, the UE receives system information via an anchor carrier. The information includes an indication that a CRS may be transmitted via a second carrier and during a paging occasion. The UE monitors the second carrier for the CRS during the paging occasion and processes the CRS. In some cases, an additional reference signal such as an NRS may be received on the second carrier during the paging occasion. Measurements may be taken of the CRS and, if present, the NRS, and the measurements of the CRS, the NRS, or both may be used to make quality determinations of the paging carrier. The UE may base power saving decisions on the quality determinations, such as whether to terminate the paging occasion early.

In accordance with the invention, a method, an apparatus, and a non-transitory computer-readable medium comprising instructions for wireless communications at a UE are provided in accordance with the independent claims.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for processing an additional reference signal received on the second carrier during the paging occasion.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for combining measurements made of both the CRS and the additional reference signal.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the additional reference signal may be an NRS.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for receiving, with the system information, a second indication of a physical cell of a cell transmitting the CRS.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, processing the CRS may include operations, features, means, or instructions for determining a quality of the second carrier based on measurements made of the CRS.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, determining the quality of the second carrier may include operations, features, means, or instructions for estimating a reference signal received power (RSRP) of the second carrier based on the CRS.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, determining the quality of the second carrier may include operations, features, means, or instructions for estimating a signal to noise ratio (SNR) of the second carrier based on the CRS.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, determining the quality of the second carrier may include operations, features, means, or instructions for determining a narrow-band reference signal received power (NRSRP) of the second carrier based on the CRS.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, determining the quality of the second carrier may include operations, features, means, or instructions for estimating an SNR of the second carrier based on the CRS, monitoring the second carrier for a paging message during the paging occasion, and affecting an early termination of the paging occasion based on the estimated SNR of the second carrier.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the UE may be an NB IoT device.

A method of wireless communications at a base station is described. The method may include identifying an anchor carrier for communicating with a UE and a second carrier for communicating with the UE, the second carrier being different from the anchor carrier, transmitting, via system information on the anchor carrier, an indication that a CRS is to be transmitted via the second carrier during a paging occasion for the UE, and transmitting the CRS via the second carrier during the paging occasion.

An apparatus for wireless communications at a base station is described. The apparatus may include a processor, memory in electronic communication with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to identify an anchor carrier for communicating with a UE and a second carrier for communicating with the UE, the second carrier being different from the anchor carrier, transmit, via system information on the anchor carrier, an indication that a CRS is to be transmitted via the second carrier during a paging occasion for the UE, and transmit the CRS via the second carrier during the paging occasion.

Another apparatus for wireless communications at a base station is described. The apparatus may include means for identifying an anchor carrier for communicating with a UE and a second carrier for communicating with the UE, the second carrier being different from the anchor carrier, transmitting, via system information on the anchor carrier, an indication that a CRS is to be transmitted via the second carrier during a paging occasion for the UE, and transmitting the CRS via the second carrier during the paging occasion.

A non-transitory computer-readable medium storing code for wireless communications at a base station is described. The code may include instructions executable by a processor to identify an anchor carrier for communicating with a UE and a second carrier for communicating with the UE, the second carrier being different from the anchor carrier, transmit, via system information on the anchor carrier, an indication that a CRS is to be transmitted via the second carrier during a paging occasion for the UE, and transmit the CRS via the second carrier during the paging occasion.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for transmitting, with the system information, a second indication of a physical cell identity for the base station.

In some wireless communications systems, a base station may transmit UE directed signals to a UE using various techniques. One technique may include beam forming or beam sweeping. In beam forming or beam sweeping, a base station may direct a transmission via a narrow beam so that only one UE or a small set of UEs receive the transmission. In one example, paging messages may be transmitted via a narrow beam. A narrow beam paging message may also be accompanied by an NRS. Additional techniques for communication between a base station and a UE may include the use of less narrow beams (e.g., wide beam communications or omnidirectional communications). One type of reference signal that may be communicated via less narrow beams may include a CRS. The timing and resources on which the various reference signals may be received may be indicated to a UE via system information.

In some examples, the UE may receive a paging message and an accompanying NRS via an anchor carrier. Additionally or alternatively, in other examples, the UE may receive the paging message and the NRS via a second carrier or a non-anchor carrier. In either case, the base station may transmit the NRS to the UE when a paging message is available. As an example, when no paging message is present, the base station may not transmit the NRS to the UE. The UE may use the NRS to determine a quality of the paging carrier. However, the UE may beneficially determine the quality of the paging carrier at more frequent intervals even in the absence of the NRS. One option could include a base station transmitting an NRS at each paging occasion, regardless of whether a paging message is to be transmitted. However, by using a dedicated resource for transmission of the NRS during each paging occasion (e.g., a NB resource block (RB)), this option renders the NB RB unavailable for use for other purposes by other networks, for example, by an LTE cell. Further, the duplicative NRS transmissions may result in interference and may puncture LTE RBs.

Therefore, a more acceptable method for performing the paging carrier quality measurements may include using a CRS, which may be transmitted to the UE during the paging occasions. The received CRS may then be used by the UE to perform quality measurements of the paging carrier. In some examples, performing these quality measurements using the CRS may include receiving system information from an anchor carrier. The system information may include an indication that a CRS may be transmitted via a non-anchor carrier during a paging occasion. The UE may then monitor the non-anchor carrier for the CRS during the paging occasion and then process the received CRS. The measurements the UE may perform using the CRS may allow the UE to determine, for example, an RSRP, an SNR, an NRSRP, or any combination thereof. In addition, the UE may use the CRS measurements to determine whether the paging occasion should be terminated early. In some examples, both the CRS and the NRS may be present and the UE may optionally combine the measurements based on both the CRS and the NRS.

Particular aspects of the subject matter described herein may be implemented to realize one or more advantages. The described techniques may support improvements in power conservation at a UE without additional signaling from a base station (e.g., without an additional load on the network). For example, the described techniques may enable a UE to perform quality measurements based on CRS and/or NRS, without the use of additional pilot signals, and perform early termination of a monitoring occasion (e.g., a paging occasion). This may result in improved power conservation at the UE and fewer transmissions from a base station, which may reduce system overhead and improve network efficiency based on fewer transmissions and shorter channel occupancy time compared to a network employing additional signaling. Additionally, based on performing quality measurements using CRS and NRS, the described techniques enable backwards compatibility with previous generations of devices and/or devices with different configurations, which may result in further improvements in network efficiency because a base station may communicate similarly with a variety of UEs.

Aspects of the disclosure are initially described in the context of a wireless communications system. Example wireless communications systems for performing measurements of the paging carrier based on CRS and/or NRS at the UE and process flows for implementing techniques discussed herein are described. Aspects of the disclosure are further illustrated by and described with reference to diagrams and flowcharts that relate to measurements for NB IoT devices.

<FIG> illustrates an example of a wireless communications system <NUM> that supports measurements for NB IoT devices in accordance with aspects of the present disclosure. The wireless communications system <NUM> includes base stations <NUM>, UEs <NUM>, and a core network <NUM>. In some examples, the wireless communications system <NUM> may be an LTE network, an LTE-A network, an LTE-A Pro network, or an NR network. In some cases, wireless communications system <NUM> may support enhanced broadband communications, ultra-reliable (e.g., mission critical) communications, low latency communications, or communications with low-cost and low-complexity devices.

In some examples, a carrier may support multiple cells, and different cells may be configured according to different protocol types (e.g., machine-type communication (MTC), NB IoT, enhanced mobile broadband (eMBB), or others) that may provide access for different types of devices.

In some examples, a UE <NUM> may also refer to a wireless local loop (WLL) station, an IoT device, an Internet of Everything (IoE) device, or an MTC device, or the like, which may be implemented in various articles such as appliances, vehicles, meters, or the like.

Other power conservation techniques for UEs <NUM> include entering a power saving "deep sleep" mode when not engaging in active communications, or operating over a limited bandwidth (e.g., according to NB communications).

For example, wireless communications system <NUM> may use a transmission scheme between a transmitting device (e.g., a base station <NUM>) and a receiving device (e.g., a UE <NUM>), where the transmitting device is equipped with multiple antennas and the receiving device is equipped with one or more antennas.

In one example, a base station <NUM> may use multiple antennas or antenna arrays to conduct beamforming operations for directional communications with a UE <NUM>. For instance, some signals (e.g., synchronization signals, reference signals, beam selection signals, or other control signals) may be transmitted by a base station <NUM> multiple times in different directions, which may include a signal being transmitted according to different beamforming weight sets associated with different directions of transmission. Transmissions in different beam directions may be used to identify (e.g., by the base station <NUM> or a receiving device, such as a UE <NUM>) a beam direction for subsequent transmission and/or reception by the base station <NUM>.

Some signals, such as data signals associated with a particular receiving device, may be transmitted by a base station <NUM> in a single beam direction (e.g., a direction associated with the receiving device, such as a UE <NUM>). In some examples, the beam direction associated with transmissions along a single beam direction may be determined based at least in in part on a signal that was transmitted in different beam directions. For example, a UE <NUM> may receive one or more of the signals transmitted by the base station <NUM> in different directions, and the UE <NUM> may report to the base station <NUM> an indication of the signal it received with a highest signal quality, or an otherwise acceptable signal quality. Although these techniques are described with reference to signals transmitted in one or more directions by a base station <NUM>, a UE <NUM> may employ similar techniques for transmitting signals multiple times in different directions (e.g., for identifying a beam direction for subsequent transmission or reception by the UE <NUM>), or transmitting a signal in a single direction (e.g., for transmitting data to a receiving device).

The single receive beam may be aligned in a beam direction determined based at least in part on listening according to different receive beam directions (e.g., a beam direction determined to have a highest signal strength, highest SNR, or otherwise acceptable signal quality based at least in part on listening according to multiple beam directions).

A carrier may be associated with a pre-defined frequency channel (e.g., an evolved universal mobile telecommunication system terrestrial radio access (E-UTRA) absolute radio frequency channel number (EARFCN)), and may be positioned according to a channel raster for discovery by UEs <NUM>. In some examples, signal waveforms transmitted over a carrier may be made up of multiple sub-carriers (e.g., using multi-carrier modulation (MCM) techniques such as orthogonal frequency division multiplexing (OFDM) or DFT-S-OFDM).

The organizational structure of the carriers may be different for different radio access technologies (e.g., LTE, LTE-A, LTE-A Pro, NR).

In other examples, some UEs <NUM> may be configured for operation using a NB protocol type that is associated with a predefined portion or range (e.g., set of subcarriers or RBs) within a carrier (e.g., "in-band" deployment of a NB protocol type).

Devices of the wireless communications system <NUM> (e.g., base stations <NUM> or UEs <NUM>) may have a hardware configuration that supports communications over a particular carrier bandwidth, or may be configurable to support communications over one of a set of carrier bandwidths. In some examples, the wireless communications system <NUM> may include base stations <NUM> and/or UEs <NUM> that support simultaneous communications via carriers associated with more than one different carrier bandwidth.

Wireless communications system <NUM> may support communication with a UE <NUM> on multiple cells or carriers, a feature which may be referred to as carrier aggregation or multi-carrier operation.

In some cases, an eCC may utilize a different symbol duration than other component carriers, which may include use of a reduced symbol duration as compared with symbol durations of the other component carriers.

Wireless communications system <NUM> may be an NR system that may utilize any combination of licensed, shared, and unlicensed spectrum bands, among others. The flexibility of eCC symbol duration and subcarrier spacing may allow for the use of eCC across multiple spectrums. In some examples, NR shared spectrum may increase spectrum utilization and spectral efficiency, specifically through dynamic vertical (e.g., across the frequency domain) and horizontal (e.g., across the time domain) sharing of resources.

In some examples, UE <NUM> may be an NB IoT device, and may frequently enter into an idle mode or a DRx mode. While in the idle mode or DRx mode, UE <NUM> periodically awakens to determine whether a paging message is available to be received. While awake, UE <NUM> measures a reference signal, such as an NRS when a paging message is available. However, if no paging message is available, UE <NUM> receives a CRS via a non-anchor carrier during a paging occasion, and the CRS is used by UE <NUM> to perform quality measurements of the paging carrier. In some examples, after receiving the CRS, UE <NUM> may then process the CRS and may perform quality measurements based on the CRS. The quality measurements that UE <NUM> may perform using the CRS may allow UE <NUM> to determine an RSRP, an SNR, an NRSRP, or any combination thereof. Additionally, UE <NUM> may use the measurements to determine whether the paging occasion should be terminated early, thus resulting in power conservation at UE <NUM>.

One method for performing the paging carrier quality measurements includes receiving system information via an anchor carrier including an indication that a CRS will be transmitted via a second carrier (e.g., a non-anchor carrier) during a paging occasion. UE <NUM> monitors the second carrier for the CRS during the paging occasion and processes the CRS, which is received via the second carrier during the paging occasion. UE <NUM> processes an additional reference signal (e.g., an NRS) received on the second carrier during the paging occasion and may combine the CRS-based measurements and the additional reference signal-based measurements. UE <NUM> may additionally receive with the system information, an indication of a PCID of a cell transmitting the CRS.

In some examples, UE <NUM> may determine a quality of the second carrier (e.g., the paging carrier) based on the measurements made based on the CRS. UE <NUM> may estimate an RSRP of the second carrier and may also estimate an SNR of the second carrier, both of which may be based on the CRS. Additionally or alternatively, UE <NUM> may determine an NRSRP of the second carrier based on the CRS.

Additionally, in some examples, UE <NUM> may estimate an SNR of the second carrier, monitor the second carrier for the paging message during the paging occasion, and may perform an early termination of the paging occasion based on the SNR of the second carrier. In some cases, early termination of the paging occasion may shorten the wake-up duration of the DRx mode and conserve power.

<FIG> illustrates an example of a wireless communications system <NUM> that supports measurements for NB IoT devices in accordance with aspects of the present disclosure. In some examples, the wireless communications system <NUM> may implement aspects of wireless communications system <NUM>. In the example of <FIG>, the wireless communications system <NUM> may include a base station <NUM>-a and a UE <NUM>-a, which may be examples of a base station <NUM> and a UE <NUM> as described with reference to <FIG>. In some cases, UEs may monitor one carrier at a time.

As illustrated in <FIG>, base station <NUM>-a may transmit, to UE <NUM>-a, a paging message on anchor carrier <NUM> during a paging occasion, and which may include an NRS <NUM>. After receiving the NRS <NUM> at UE <NUM>-a, the NRS <NUM> may be used by UE <NUM>-a to perform quality measurements of the anchor carrier. In some examples, UE <NUM>-a may make serving cell measurements of the paging carrier and/or SNR measurements of the paging carrier based on the NRS <NUM>. The quality measurements based on the NRS <NUM> may be used to detect excessive interference conditions and/or may be used to determine whether early termination for the paging occasion may be appropriate.

In some examples, UE <NUM>-a may be an NB IoT device which may be configured to receive an NPDCCH. The NPDCCH may be communicated via the non-anchor carrier <NUM> and may be transmitted by, for example, base station <NUM>-b. In some examples, UE <NUM>-a may be in an idle mode or a DRx mode. As UE <NUM>-a switches out of the DRx mode to wake up, based on the UE identity, UE <NUM>-a may map to a specific paging carrier which may be any non-anchor carrier. Thus, although UE <NUM>-a may be waking up to a specific paging carrier, the carrier may be an anchor carrier or a non-anchor carrier. In the example UE <NUM>-a wakes up and maps to a non-anchor carrier, a paging message may not be present.

Given this UE configuration, in some examples, NRS <NUM> may not be received unless a paging message is present. In some examples, the paging message may not be present to save bandwidth. In this example, the NB IoT RB may be used for an LTE cell when it is not in use, thus the NB IoT RB may not be available for the paging message. In other examples, the addition of NRS tones may produce interference to LTE cells (e.g., by puncturing of the LTE RBs). Without the paging message, UE <NUM>-a may not receive the NRS <NUM> a large percentage of the time. Accordingly, a paging message may not be assumed for UE <NUM>-a in a DRx mode.

In some examples of <FIG>, instead of receiving and using the NRS <NUM> to take the quality measurements, UE <NUM>-a may receive the CRS <NUM> on non-anchor carrier <NUM>. UE <NUM>-a may use the LTE CRS tones of the CRS <NUM> to take the quality measurements (e.g., SNR or RSRP measurements of the paging carrier) without using the NRS <NUM>. Quality measurements of the paging carrier, based on the CRS <NUM>, may be practical as no additional load may be placed on the network due to the lack of additional pilot signals transmitted by base station <NUM>-a. Additionally, when base station <NUM>-a transmits the system information to UE <NUM>-a there may little impact on the network, due to the low additional processing complexity. Further, using the CRS <NUM> may provide backwards compatibility with previous generation UEs and/or UEs that may be differently configured.

<FIG> illustrates an example of a wireless communications system <NUM> that supports measurements for NB IoT devices in accordance with aspects of the present disclosure. In some examples, the wireless communications system <NUM> may implement aspects of wireless communications systems <NUM> and <NUM>. In the example of <FIG>, the wireless communications system <NUM> may include an anchor carrier <NUM> and a non-anchor paging carrier <NUM> which may be examples of anchor carriers and non-anchor carriers as discussed with respect to <FIG>.

As illustrated in <FIG>, an anchor carrier <NUM> and a non-anchor paging carrier <NUM> may be used to carry the paging message as previously discussed with respect to <FIG>. In <FIG>, and as discussed with respect to <FIG> and <FIG>, UE <NUM> (not illustrated in <FIG>) may receive a CRS and may take CRS-based measurements of the non-anchor paging carrier <NUM>. In some examples, non-anchor paging carrier may experience interference <NUM> which may be detected by taking quality measurements of non-anchor paging carrier <NUM>, and based on the received CRS. In <FIG> and similar to <FIG>, UE <NUM> may be configured to receive paging via NPDCCH on non-anchor paging carrier <NUM>.

In some examples of <FIG>, the paging message and, accordingly, the NRS may not be present for reasons discussed herein. Because the NRS or pilot signal may not be guaranteed when a paging message is not present, UE <NUM> may not be able to appropriately decode received signals. In some examples, the pilot signal may be a transmitted signal which may be received by a device (e.g., UE <NUM>), so that the device may decode the received signal. In <FIG>, in the absence of the NRS or pilot signal, interference <NUM> may not be measured on the non-anchor paging carrier.

In some examples of <FIG>, the absence of the NRS may impact the receiver design of UE <NUM>. Due to the NRS absence, UE <NUM> may not make serving cell measurements and may attempt to tune to the anchor carrier <NUM> for this measurement, thus resulting in wasted power at UE <NUM>. UE <NUM> may make serving cell measurements of received power, which may aid in the determination of cell selection and cell re-selection. Further, UE <NUM> may use NRS-based SNR measurements of the paging carrier for determining whether or not to terminate the paging occasion early. However, due to the lack of NRS or the pilot signal, UE <NUM> may be unable to make the SNR measurement of the paging carrier. As such, UE <NUM> may be unable to terminate the paging occasion early.

For example, non-anchor paging carrier <NUM> may experience interference <NUM>, but UE <NUM> may be unable to detect the interference <NUM> due to the lack of NRS. Accordingly, UE <NUM> may be unable to determine whether or not the interference <NUM> is excessive (e.g., exceeds a threshold interference level that results in an insufficient RSRP or SNR, among other quality measurements). As such, UE <NUM> may be unable to determine to terminate the paging occasion early if the interference <NUM> is associated with excessive interference conditions. In some cases, this may result in additional power consumption by UE <NUM> due to the extension of the "on" duration of every UE DRx cycle (e.g., based on unsuccessfully receiving transmissions from base station <NUM> due to the interference <NUM>).

<FIG>illustrate examples of timelines <NUM>, <NUM>, and <NUM>, respectively, for wireless communications that support measurements for NB IoT devices in accordance with aspects of the present disclosure. In some examples, the timelines <NUM> may implement aspects of wireless communications systems <NUM>, <NUM> and <NUM>. In the examples of <FIG>, the timeline <NUM> may include representations of a paging message <NUM> and NRS <NUM>, which may be an example of NRS <NUM> with a paging message as described with reference to <FIG>. In the examples of <FIG>, the timelines <NUM> and <NUM> may also include representations of a CRS <NUM>.

<FIG> illustrate three different combinations of signals and the way in which the signals may be received during a paging occasion and at a UE <NUM> (UE <NUM> not illustrated in <FIG>). In <FIG>, NRS <NUM> may be transmitted via a paging message <NUM>, during a paging opportunity, and may be transmitted on an anchor carrier. In <FIG>, CRS <NUM> may be transmitted during a paging occasion and on a non-anchor carrier, and in <FIG>, NRS <NUM>, CRS <NUM>, and the paging message <NUM> may be communicated on either one or both of an anchor carrier and non-anchor carrier.

In some examples, it may be difficult for UE <NUM> to receive the NRS <NUM> in the absence of paging message <NUM>. Without paging message <NUM>, receipt of NRS <NUM> from a non-anchor carrier may not be guaranteed (e.g., may be unlikely). In the example, UE <NUM> may not receive NRS <NUM> and, accordingly, UE <NUM> may be unable to take quality measurements of the paging carrier. The absence of NRS <NUM> may result in UE <NUM> unnecessarily extending its "on" duration of the DRx cycle and wasting power, as previously discussed. In some implementations, even though NRS <NUM> may be absent, UE <NUM> may perform quality measurements (e.g., SNR or RSRP) using LTE CRS tones, as discussed in further detail herein.

In some examples of <FIG>, UE <NUM> may be configured to receive a paging message via NPDCCH on a non-anchor carrier. A base station <NUM> may transmit, using a paging carrier or a non-anchor carrier, CRS <NUM> during a paging occasion. In some aspects, base station <NUM> may transmit CRS <NUM> via system information and without a paging message. In some examples, the paging carrier may be an NB IoT paging carrier and may be in an in-band same PCI mode. In this mode, the network may advertise the availability of CRS tones during a paging occasion, if available. In some examples, the network may advertise the availability of the CRS tones by using the paging carrier to transmit system information, which may include an indication that a CRS (e.g., CRS <NUM>) may be transmitted via a second carrier during a paging occasion. In some examples, the second carrier may be different from the anchor carrier (e.g., may be a non-anchor carrier). Continuing the example, UE <NUM> may monitor the non-anchor carrier for the CRS during the paging occasion and may receive the CRS on the second carrier during the paging occasion. After receiving the CRS, UE <NUM> may process the CRS.

In some examples of <FIG>, the paging carrier may be an NB IoT paging carrier and may be in an in-band diff PCI mode. In this mode, the network may advertise the availability of CRS tones during a paging occasion, if available, and may additionally advertise an LTE PCID for a cell. In some aspects, UE <NUM> may use the PCID to calculate a scrambling sequence. The network may advertise the availability of CRS tones and the base station <NUM> may transmit a paging message on a paging carrier (e.g., a non-anchor carrier), which may include an indication that a CRS will be transmitted during a certain time duration, or during a number of time durations, where the timae durations may be paging occasions. In some examples of an in-band case or scenario, the NB IoT may be deployed in a single RB for an LTE cell.

Because UE <NUM> may have the availability of CRS in paging occasions, UE <NUM> may perform a number of different quality measurements for the paging carrier. In some examples, UE <NUM> may run a parallel SNR/RSRP estimator, which may be based on the CRS <NUM>. In some examples, UE <NUM> may compute NRSRP based on the CRS, even though the NRS may not be present. In computing NRSRP, UE <NUM> may refrain from tuning to the anchor carrier for serving cell measurements, which may result in power conservation. Additionally or alternatively, UE <NUM> may use the CRS-based SNR to make the determination of whether to perform early termination of the paging occasion. UE <NUM> may also detect the presence of an NRS-based CRS-SNR estimate. In some examples, UE <NUM> may determine that the NRS is not present and therefore determine that the page is not present. Accordingly, UE <NUM> may determine that early termination of the paging occasion is appropriate.

As illustrated in <FIG>, UE <NUM> may receive NRS <NUM> and CRS <NUM> via the paging message <NUM>, which may be transmitted on either one or both of the anchor carrier and/or the non-anchor carrier. UE <NUM> may optionally combine the statistics of the NRS and the CRS (e.g., may combine CRS-based quality measurements with NRS-based quality measurements when the NRS is present). As discussed with reference to <FIG>, the quality measurements of the paging carrier may be used to terminate the paging occasion early, thus ending the "on" duration for the DRx cycle of UE <NUM>.

<FIG> illustrates an example of a process flow <NUM> that supports measurements for NB IoT devices in accordance with aspects of the present disclosure. In some examples, process flow <NUM> may implement aspects of wireless communications system <NUM>. In the example of <FIG>, the process flow <NUM> may include a base station <NUM>-b and a UE <NUM>-b, which may be examples of a base station <NUM> and a UE <NUM> as described with reference to <FIG> and a base station <NUM>-a and a UE <NUM>-a as described with reference to <FIG>. Additionally, in the example of <FIG>, the process flow <NUM> may include one example of a base station transmitting PDCCHs to a UE, which may be examples of the transmitted PDCCHs with UE-specific configurations as discussed with reference to <FIG>.

In <FIG>, optional steps may be depicted with dotted lines. Additionally, although the steps of <FIG> are discussed and numbered in an order, the steps may be performed in any appropriate order, all steps may be performed, or some steps may be omitted as appropriate.

At <NUM>, base station <NUM>-b may generate system information. In some examples, base station <NUM>-b may generate system information for transmission on a first carrier (e.g., an anchor carrier) and the system information may include an indication that a CRS will be transmitted on a second carrier different from the first carrier (e.g., a non-anchor carrier).

At <NUM>, base station <NUM>-b may transmit the system information on the anchor carrier. UE <NUM>-b may receive the system information via the anchor carrier including an indication that the CRS will be transmitted during a paging occasion and via the second carrier (e.g., a non-anchor carrier). Additionally or alternatively, the system information may include an indication of an availability of the CRS (e.g., an availability of CRS tones).

At <NUM>, UE <NUM>-b may monitor the second carrier during the paging occasion as indicated in the system information received at <NUM>. At <NUM>, base station <NUM>-b may transmit the CRS via the second carrier during the paging occasion. Accordingly, UE <NUM> may receive the CRS on the second carrier during the paging occasion and, at <NUM>, may process the CRS. In some examples, UE <NUM>-b may process the CRS by performing quality measurements of the paging carrier as discussed in further detail in <FIG>.

At <NUM>, UE <NUM>-b may optionally monitor the second carrier for an NRS. At <NUM>, base station <NUM>-b may optionally transmit the NRS (e.g., based on whether a page is present) and UE <NUM>-b may receive the NRS based on whether base station <NUM>-b transmitted the NRS. In some examples, base station <NUM>-b may transmit the NRS with a paging message, such that in the absence of a paging message base station <NUM>-b may not transmit the NRS and the NRS may be unavailable to UE <NUM>-b.

At <NUM>, UE <NUM>-b may optionally process NRS. In some examples, UE <NUM>-b may process the NRS by taking quality measurements of the paging carrier. At <NUM>, UE <NUM>-b may optionally combine the CRS and NRS statistics (e.g., UE <NUM>-b may combine the CRS-based quality measurements and the NRS-based quality measurements).

In some implementations, processing the CRS at UE <NUM>-b may include running a parallel SNR/RSRP estimator, which may be based on the CRS. In some examples, UE <NUM>-b may compute NRSRP based on the CRS (e.g., when NRS is not present). In computing NRSRP, UE <NUM>-b may refrain from tuning to the anchor carrier for serving cell measurements, which may result in power conservation. Additionally or alternatively, UE <NUM>-b may use the CRS-based SNR to determine whether to perform early termination of the paging occasion. UE <NUM>-b may also detect the presence of an NRS-based CRS-SNR estimate.

<FIG> shows a diagram <NUM> of a device <NUM> that supports measurements for NB IoT devices in accordance with aspects of the present disclosure. The device <NUM> may be an example of aspects of a UE <NUM> as described herein. The device <NUM> may include a receiver <NUM>, a communications manager <NUM>, and a transmitter <NUM>. The device <NUM> may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

The receiver <NUM> may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to measurements for NB IoT devices, etc.). Information may be passed on to other components of the device <NUM>. The receiver <NUM> may be an example of aspects of the transceiver <NUM> described with reference to <FIG>. The receiver <NUM> may utilize a single antenna or a set of antennas.

The communications manager <NUM> may receive system information via an anchor carrier including an indication that a CRS will be transmitted in a second carrier different from the anchor carrier during a paging occasion, monitor, based on the indication, the second carrier for the CRS during the paging occasion, and process the CRS received on the second carrier during the paging occasion. The communications manager <NUM> may be an example of aspects of the communications manager <NUM> described herein.

In some examples, the communications manager <NUM> may be implemented as an integrated circuit or chipset for a mobile device modem, and the receiver <NUM> and transmitter <NUM> may be implemented as analog components (e.g., amplifiers, filters, antennas) coupled with the mobile device modem to enable wireless transmission and reception over one or more bands or carriers.

The communications manager <NUM> as described herein may be implemented to realize one or more potential advantages. One implementation may allow the device <NUM> to measure interference conditions during paging occasions and to perform an early termination of paging occasions without additional signaling from a base station, such as a base station <NUM> as described herein. This may enable the device <NUM> to operate shorter "on" or wake-up durations in a DRx mode, which may result in improved power savings and longer battery life.

Further, based on measuring interference conditions without additional signaling from a base station, the communications manager <NUM> may achieve shorter "on" or wake-up durations without increasing a number of reception opportunities the device <NUM> may monitor. Likewise, the communications manager <NUM> may perform fewer processing operations and lower processing complexity compared to a device that employs additional signaling to perform quality measurements.

<FIG> shows a diagram <NUM> of a device <NUM> that supports measurements for NB IoT devices in accordance with aspects of the present disclosure. The device <NUM> may be an example of aspects of a device <NUM>, or a UE <NUM> as described herein. The device <NUM> may include a receiver <NUM>, a communications manager <NUM>, and a transmitter <NUM>. The device <NUM> may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

The receiver <NUM> may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, information channels related to measurements for NB IoT devices, etc.). Information may be passed on to other components of the device <NUM>. The receiver <NUM> may be an example of aspects of the transceiver <NUM> described with reference to <FIG>. The receiver <NUM> may utilize a single antenna or a set of antennas.

The communications manager <NUM> may be an example of aspects of the communications manager <NUM> as described herein. The communications manager <NUM> may include a system information receiving component <NUM>, a monitoring component <NUM>, and a processing component <NUM>. The communications manager <NUM> may be an example of aspects of the communications manager <NUM> described herein.

The system information receiving component <NUM> may receive system information via an anchor carrier including an indication that a CRS will be transmitted in a second carrier different from the anchor carrier during a paging occasion.

The monitoring component <NUM> may monitor, based on the indication, the second carrier for the CRS during the paging occasion.

The processing component <NUM> may process the CRS received on the second carrier during the paging occasion.

<FIG> shows a diagram <NUM> of a communications manager <NUM> that supports measurements for NB IoT devices in accordance with aspects of the present disclosure. The communications manager <NUM> may be an example of aspects of a communications manager <NUM>, a communications manager <NUM>, or a communications manager <NUM> described herein. The communications manager <NUM> may include a system information receiving component <NUM>, a monitoring component <NUM>, a processing component <NUM>, a measurement component <NUM>, a quality determination component <NUM>, a reference signal estimation component <NUM>, an SNR estimation component <NUM>, a NRSRP determination component <NUM>, and an early termination component <NUM>. Each of these modules may communicate, directly or indirectly, with one another (e.g., via one or more buses).

The system information receiving component <NUM> may receive system information via an anchor carrier including an indication that a CRS will be transmitted in a second carrier different from the anchor carrier during a paging occasion. In some examples, the system information receiving component <NUM> may receive, with the system information, a second indication of a physical cell of a cell transmitting the CRS.

The monitoring component <NUM> may monitor, based on the indication, the second carrier for the CRS during the paging occasion. In some examples, the monitoring component <NUM> may monitor the second carrier for a paging message during the paging occasion.

The processing component <NUM> may process the CRS received on the second carrier during the paging occasion. In some examples, the processing component <NUM> may process an additional reference signal received on the second carrier during the paging occasion.

The measurement component <NUM> may combine measurements made of both the CRS and the additional reference signal.

The quality determination component <NUM> may determine a quality of the second carrier based on measurements made of the CRS.

The reference signal estimation component <NUM> may estimate an RSRP of the second carrier based on the CRS.

The SNR estimation component <NUM> may estimate an SNR of the second carrier based on the CRS.

The NRSRP determination component <NUM> may determine an NRSRP of the second carrier based on the CRS.

The early termination component <NUM> may affect an early termination of the paging occasion based on the estimated SNR of the second carrier.

<FIG> shows a diagram of a system <NUM> including a device <NUM> that supports measurements for NB IoT devices in accordance with aspects of the present disclosure. The device <NUM> may be an example of or include the components of device <NUM>, device <NUM>, or a UE <NUM> as described herein. The device <NUM> may include components for bi-directional voice and data communications including components for transmitting and receiving communications, including a communications manager <NUM>, an I/O controller <NUM>, a transceiver <NUM>, an antenna <NUM>, memory <NUM>, and a processor <NUM>. These components may be in electronic communication via one or more buses (e.g., bus <NUM>).

The communications manager <NUM> may receive system information via an anchor carrier including an indication that a CRS will be transmitted in a second carrier different from the anchor carrier during a paging occasion, monitor, based on the indication, the second carrier for the CRS during the paging occasion, and process the CRS received on the second carrier during the paging occasion.

In some cases, the memory <NUM> may contain, among other things, a basic I/O system (BIOS) which may control basic hardware or software operation such as the interaction with peripheral components or devices.

The processor <NUM> may include an intelligent hardware device, (e.g., a general-purpose processor, a DSP, a central processing unit (CPU), a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof). In some cases, the processor <NUM> may be configured to operate a memory array using a memory controller. In other cases, a memory controller may be integrated into the processor <NUM>. The processor <NUM> may be configured to execute computer-readable instructions stored in a memory (e.g., the memory <NUM>) to cause the device <NUM> to perform various functions (e.g., functions or tasks supporting measurements for NB IoT devices).

<FIG> shows a diagram <NUM> of a device <NUM> that supports measurements for NB IoT devices in accordance with aspects of the present disclosure. The device <NUM> may be an example of aspects of a base station <NUM> as described herein. The device <NUM> may include a receiver <NUM>, a communications manager <NUM>, and a transmitter <NUM>. The device <NUM> may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

The communications manager <NUM> may identify an anchor carrier for communicating with a UE and a second carrier for communicating with the UE, the second carrier being different from the anchor carrier, transmit, via system information on the anchor carrier, an indication that a CRS is to be transmitted via the second carrier during a paging occasion for the UE, and transmit the CRS via the second carrier during the paging occasion. The communications manager <NUM> may be an example of aspects of the communications manager <NUM> described herein.

If implemented in code executed by a processor, the functions of the communications manager <NUM>, or its sub-components may be executed by a general-purpose processor, a DSP, an ASIC, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described in the present disclosure.

In some examples, the communications manager <NUM>, or its sub-components, may be combined with one or more other hardware components, including but not limited to an I/O component, a transceiver, a network server, another computing device, one or more other components described in the present disclosure, or a combination thereof in accordance with various aspects of the present disclosure.

The communications manager <NUM> as described herein may be implemented to realize one or more potential advantages. One implementation may enable the communications manager <NUM> to support improved power conservation at a UE, such as a UE <NUM>, without employing additional signaling from the device <NUM>. For example, based on enabling a UE to perform quality measurements on a CRS and/or an NRS the device <NUM> may refrain from transmitting additional pilot signals, which may result in lower system overhead and improved network efficiency compared to devices employing additional pilot signals for quality measurements. In some implementations, the device <NUM> may contribute to improved network efficiency based on causing lower interference levels than devices employing additional pilot signal transmissions.

<FIG> shows a diagram <NUM> of a device <NUM> that supports measurements for NB IoT devices in accordance with aspects of the present disclosure. The device <NUM> may be an example of aspects of a device <NUM>, or a base station <NUM> as described herein. The device <NUM> may include a receiver <NUM>, a communications manager <NUM>, and a transmitter <NUM>. The device <NUM> may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

The communications manager <NUM> may be an example of aspects of the communications manager <NUM> as described herein. The communications manager <NUM> may include an anchor carrier identification component <NUM>, a system information transmission component <NUM>, and a CRS transmission component <NUM>. The communications manager <NUM> may be an example of aspects of the communications manager <NUM> described herein.

The anchor carrier identification component <NUM> may identify an anchor carrier for communicating with a UE and a second carrier for communicating with the UE, the second carrier being different from the anchor carrier.

The system information transmission component <NUM> may transmit, via system information on the anchor carrier, an indication that a CRS is to be transmitted via the second carrier during a paging occasion for the UE.

The CRS transmission component <NUM> may transmit the CRS via the second carrier during the paging occasion.

<FIG> shows a diagram <NUM> of a communications manager <NUM> that supports measurements for NB IoT devices in accordance with aspects of the present disclosure. The communications manager <NUM> may be an example of aspects of a communications manager <NUM>, a communications manager <NUM>, or a communications manager <NUM> described herein. The communications manager <NUM> may include an anchor carrier identification component <NUM>, a system information transmission component <NUM>, a CRS transmission component <NUM>, and a physical cell identity indication transmission component <NUM>. Each of these modules may communicate, directly or indirectly, with one another (e.g., via one or more buses).

The physical cell identity indication transmission component <NUM> may transmit, with the system information, a second indication of a physical cell identity for the base station.

<FIG> shows a diagram of a diagram <NUM> including a device <NUM> that supports measurements for NB IoT devices in accordance with aspects of the present disclosure. The device <NUM> may be an example of or include the components of device <NUM>, device <NUM>, or a base station <NUM> as described herein. The device <NUM> may include components for bi-directional voice and data communications including components for transmitting and receiving communications, including a communications manager <NUM>, a network communications manager <NUM>, a transceiver <NUM>, an antenna <NUM>, memory <NUM>, a processor <NUM>, and an inter-station communications manager <NUM>. These components may be in electronic communication via one or more buses (e.g., bus <NUM>).

The communications manager <NUM> may identify an anchor carrier for communicating with a UE and a second carrier for communicating with the UE, the second carrier being different from the anchor carrier, transmit, via system information on the anchor carrier, an indication that a CRS is to be transmitted via the second carrier during a paging occasion for the UE, and transmit the CRS via the second carrier during the paging occasion.

The processor <NUM> may include an intelligent hardware device, (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof). In some cases, the processor <NUM> may be configured to operate a memory array using a memory controller. In some cases, a memory controller may be integrated into processor <NUM>. The processor <NUM> may be configured to execute computer-readable instructions stored in a memory (e.g., the memory <NUM>) to cause the device <NUM> to perform various functions (e.g., functions or tasks supporting measurements for NB IoT devices).

<FIG> shows a flowchart illustrating a method <NUM> that supports measurements for NB IoT devices in accordance with aspects of the present disclosure. The operations of method <NUM> are implemented by a UE <NUM> or its components as described herein. For example, the operations of method <NUM> may be performed by a communications manager as described with reference to <FIG>. In some examples, a UE may execute a set of instructions to control the functional elements of the UE to perform the functions described herein. Additionally or alternatively, a UE may perform aspects of the functions described herein using special-purpose hardware.

At <NUM>, the UE receives system information via an anchor carrier including an indication that a CRS will be transmitted in a second carrier different from the anchor carrier during a paging occasion. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a system information receiving component as described with reference to <FIG>.

At <NUM>, the UE monitors, based on the indication, the second carrier for the CRS during the paging occasion. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a monitoring component as described with reference to <FIG>.

At <NUM>, the UE processes the CRS received on the second carrier during the paging occasion. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a processing component as described with reference to <FIG>.

At <NUM>, the UE processes an additional reference signal received on the second carrier during the paging occasion. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a processing component as described with reference to <FIG>.

<FIG> shows a flowchart illustrating a method <NUM> that supports measurements for NB IoT devices in accordance with aspects of the present disclosure. The operations of method <NUM> may be implemented by a UE <NUM> or its components as described herein. For example, the operations of method <NUM> may be performed by a communications manager as described with reference to <FIG>. In some examples, a UE may execute a set of instructions to control the functional elements of the UE to perform the functions described herein. Additionally or alternatively, a UE may perform aspects of the functions described herein using special-purpose hardware.

At <NUM>, the UE may receive system information via an anchor carrier including an indication that a CRS will be transmitted in a second carrier different from the anchor carrier during a paging occasion. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a system information receiving component as described with reference to <FIG>.

At <NUM>, the UE may monitor, based on the indication, the second carrier for the CRS during the paging occasion. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a monitoring component as described with reference to <FIG>.

At <NUM>, the UE may process the CRS received on the second carrier during the paging occasion. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a processing component as described with reference to <FIG>.

At <NUM>, the UE may determine a quality of the second carrier based on measurements made of the CRS. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a quality determination component as described with reference to <FIG>.

<FIG> shows a flowchart illustrating a method <NUM> that supports measurements for NB IoT devices in accordance with aspects of the present disclosure. The operations of method <NUM> may be implemented by a base station <NUM> or its components as described herein. For example, the operations of method <NUM> may be performed by a communications manager as described with reference to <FIG>. In some examples, a base station may execute a set of instructions to control the functional elements of the base station to perform the functions described herein. Additionally or alternatively, a base station may perform aspects of the functions described herein using special-purpose hardware.

At <NUM>, the base station may identify an anchor carrier for communicating with a UE and a second carrier for communicating with the UE, the second carrier being different from the anchor carrier. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by an anchor carrier identification component as described with reference to <FIG>.

At <NUM>, the base station may transmit, via system information on the anchor carrier, an indication that a CRS is to be transmitted via the second carrier during a paging occasion for the UE. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a system information transmission component as described with reference to <FIG>.

At <NUM>, the base station may transmit the CRS via the second carrier during the paging occasion. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a CRS transmission component as described with reference to <FIG>.

At <NUM>, the base station may transmit, with the system information, a second indication of a physical cell identity for the base station. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a physical cell identity indication transmission component as described with reference to <FIG>.

Techniques described herein may be used for various wireless communications systems such as CDMA, TDMA, FDMA, OFDMA, single carrier frequency division multiple access (SC-FDMA), and other systems.

Also, as used herein, including in the claims, "or" as used in a list of items (for example, a list of items prefaced by a phrase such as "at least one of" or "one or more of") indicates a disjunctive list such that, for example, a list of "at least one of A, B, or C" means A or B or C or AB or AC or BC or ABC (i.e., A and B and C).

By way of example, and not limitation, non-transitory computer-readable media may include RAM, ROM, electrically erasable programmable ROM (EEPROM), flash memory, compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that can be used to carry or store desired program code means in the form of instructions or data structures and that can be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor.

In some instances, well-known structures and devices are shown in diagram form in order to avoid obscuring the concepts of the described examples.

Claim 1:
A method (<NUM>) for wireless communications performed by a user equipment, UE (<NUM>), comprising:
receiving (<NUM>) system information via an anchor carrier (<NUM>) including an indication that a cell-specific reference signal will be transmitted in a second carrier different from the anchor carrier during a paging occasion;
determining whether a paging message is available to be received;
monitoring (<NUM>), based at least in part on the indication, the second carrier for the cell-specific reference signal during the paging occasion; and
processing (<NUM>) the cell-specific reference signal received on the second carrier during the paging occasion;
wherein when it is determined that no paging message is available to be received:
determining a quality of the second carrier based on measurements made of the cell-specific reference signal; and
wherein when it is determined that a paging message is available to be received
processing an additional reference signal received on the second carrier during the paging occasion, wherein the additional reference signal is a narrow-band signal; and
determining a quality of the second carrier based on measurements made of the cell-specific reference signal and the additional reference signal.