爱立信：2023年RedCap白皮书-扩展5G设备生态系统惠及消费者和行业（英文版）（24页）.pdf

1、Ericsson White PaperGFTL-23:000064 UenFebruary 2023RedCap-expanding the 5G device ecosystem for consumers and industries RedCap-expanding the 5G device ecosystem for consumers and industries ContentFebruary 20232ContentIntroduction 3Use cases and market potential 5Reducing device cost and complexity

2、 7Addressing diverse battery life requirements 10Network deployment aspects for RedCap devices 13Further evolution and LTE-to-NR migration for IoT use cases 17Conclusion 19Glossary 20References 21Authors 22RedCap-expanding the 5G device ecosystem for consumers and industries IntroductionFebruary 202

3、33IntroductionSince the number of personal smartphone subscriptions is limited by the size of the human population,the number of Internet of Things(IoT)devices is predicted to have a stronger growth than smartphone subscriptions in the coming years.The IoT segment served by cellular networks can be

4、divided into Massive IoT,Broadband IoT,Critical IoT,and Industrial Automation IoT,where Broadband IoT is forecasted to constitute 60 percent of the cellular IoT connections by the end of 2028 1.Broadband IoT includes both wide-area and local-area use cases that require higher throughput,lower latenc

5、y,and larger data volumes than what Massive IoT technologies can support.These use cases include,for example,smart wearables and industrial sensors.In the past,Broadband IoT use cases were often served by 4G long-term evolution(LTE)device categories 1 and 4.The device complexity,and hence the device

6、 cost,has so far been too high for 5G New Radio(NR)to be suited to Broadband IoT,which motivated the introduction of reduced capability(RedCap)5G NR devices in 3GPP Release 17 2.Figure 1 illustrates different 4G/5G device types.At the low end,there is the NB-IoT device category(Cat-NB1)and the LTE-M

7、 device category(Cat-M1),which both support relatively low data rates suitable for Massive IoT use cases.Since 3GPP Release 15,both NB-IoT and LTE-M fulfill the 5G massive machine-type communications(mMTC)requirements and are therefore components of both 4G and 5G.At the high end,both LTE and NR hav

8、e device types for high peak rates for demanding use cases.In between the low and the high end,LTE offers several device categories(that is,Cat-1/2/3/4),and RedCap provides corresponding NR-based device types for this mid-range segment.RedCap-expanding the 5G device ecosystem for consumers and indus

9、tries IntroductionFebruary 20234The simplest RedCap device,that is,a RedCap device with the lowest possible complexity,is expected to reduce the modem complexity by about 65 percent for low-or mid-band(FR1)devices,and by about 50 percent for high-band(FR2)devices,while high enough peak data rates ar

10、e maintained to still serve more demanding IoT use cases.A RedCap device equipped with more advanced(but not mandatory)capabilities can support much higher peak rates.For example,a RedCap device with two receive antenna branches and downlink multiple-input multiple-output(MIMO)layers can support twi

11、ce as high downlink peak rates as the simplest RedCap device,since this allows dual-stream transmissions over two MIMO layers.The other aspect which is needed to fulfill IoT requirements is low energy consumption,and this has been enabled by the introduction of extended discontinuous reception(eDRX)

12、cycles and relaxations for radio resource management(RRM)monitoring(on top of the Release 16 measurement relaxations which can also be supported by RedCap devices).In combination,the introduced features provide a substantial complexity reduction and an extended battery life for RedCap devices which

13、enable NR to efficiently address Broadband IoT use cases ranging from factory automation and Industry 4.0 to low-end augmented reality(AR)and virtual reality(VR)applications.Higher LTE categoriesLegacy NRRel-17 RedCapRel-18 RedCapLTE-M category M1NB-IoT category NB1LTE Category 1LTE Category 2LTE Ca

14、tegory 3LTE Category 44G5GPeak data rateFigure 1:Illustration of 4G and 5G device types.RedCap-expanding the 5G device ecosystem for consumers and industries Use cases and market potentialFebruary 20235Use cases and market potentialThe introduction of RedCap will enable a single network,i.e.,a 5G st

15、andalone network consisting of both RAN and core network,to address a variety of use cases for industry digitalization and business transformation.Furthermore,RedCap will help expand the 5G ecosystem and connect significantly more devices to 5G networks.This includes upgrading the LTE-based networks

16、 that have been deployed to provide global IoT coverage.With the introduction of RedCap,a smooth migration to NR for supporting such use cases can then be accomplished without the need for network deployments with multiple RATs.Examples of use cases that will be addressed by RedCap devices include w

17、earables such as smart watches,wearable medical devices,and low-end AR/VR glasses,video surveillance,industrial sensors,smart grids,and so on(see Figure 2).These use cases have a huge market potential,worth tens of billions of dollars.For example,the global end-user spending on wearables alone was e

18、stimated to be USD 81.5 billion in 2021,an increase of 18 percent compared to 2020,and is estimated to increase to USD 94 billion in 2022,according to Gartner 3.For industrial applications,RedCap services can provide robust wireless connectivity and seamless mobility support through 5G networks for

19、industrial Figure 2:Representative RedCap use cases.CameraSmart gridIndustrial sensorSmart glassesWearableHealth monitoringRedCapRedCap-expanding the 5G device ecosystem for consumers and industries Use cases and market potentialFebruary 20236devices enabling cost-efficient Industry 4.0 transformati

20、on.Each addressable RedCap use case has its own set of requirements which,compared to regular 5G NR devices,is less demanding in terms of data rates and latency,yet more stringent when it comes to device cost/complexity and power consumption.However,the battery life requirements for RedCap use cases

21、 are relatively relaxed compared to those of mMTC use cases.In fact,as illustrated in Figure 3,RedCap is designed to efficiently support use cases whose requirements fall between the more extreme requirements defined for mMTC,ultra-reliable low-latency communications(URLLC),and enhanced mobile broad

22、band(eMBB).However,RedCap devices may also be suitable for moderate(less extreme)mMTC/URLLC/eMBB use cases.For example,when comparing RedCap requirements with eMBB,URLLC,and mMTC use cases,the following can be noted 2:Latency:The target for URLLC is about 1 ms,while for RedCap use cases it is less t

23、han 100 ms for industrial sensors and less than 500 ms for video surveillance.However,these are minimum requirements,and it is worth noting that RedCap devices can in fact achieve much better latency than this.Data rates:The target peak rate for eMBB is up to 20 Gbps in downlink and 10 Gbps in uplin

24、k,while for the most demanding RedCap use cases(e.g.,wearables)it is up to 150 Mbps in downlink and 50 Mbps in uplink.Battery life:The target for mMTC is 10 to 15 years battery life,while for RedCap use cases it is a few years for industrial sensors and one to two weeks for wearables.Again,these are

25、 minimum requirements,and RedCap devices may be able to achieve a longer battery life.With RedCap and its evolution,5G can efficiently address mid-tier Broadband IoT use cases in addition to the three key usage scenarios(eMBB,URLLC,mMTC)using any available 5G spectrum,both time-division duplex(TDD)a

26、nd frequency-division duplex(FDD),in all(low/mid/high)frequency bands.Our analysis shows that RedCap can sufficiently meet requirements of various Broadband IoT use cases in terms of data rates,latency,battery life,and small form factors.Compared to LTE device category 4,RedCap offers similar data r

27、ates with improved latency and potential support for various 5G NR features including enhanced positioning(important for personal trackers),millimeter-wave operations with advanced beamforming support,and network slicing.Figure 3:RedCap requirements compared to eMBB,URLLC,and mMTC.RedCapmMTCURLLCeMB

28、BLow cost and long battery lifeLow latencyHigh data rateRedCap-expanding the 5G device ecosystem for consumers and industries Reducing device cost and complexity February 20237Reducing device cost and complexity Today,many of the targeted use cases for RedCap can be served by low-end LTE devices,whi

29、ch have substantially lower device hardware requirements than the simplest NR device.Therefore,as mentioned in the Introduction,the need to introduce a lower-complexity NR device type with reduced capabilities roughly corresponding to the capabilities of a low-end LTE device has been identified.The

30、NR modem cost/complexity reduction is accomplished by using the techniques summarized in Table 1 below 2.In the table,the“Simplest regular 5G device”corresponds to a basic 5G NR device such as a smartphone with only the minimum capabilities that are mandatory to support for such a device,whereas the

31、“Simplest RedCap device”corresponds to a basic RedCap device with only the minimum capabilities that are mandatory to support for a RedCap device,and the“Most advanced RedCap device”corresponds to a RedCap device with the most advanced(but optional)capabilities that can be implemented.Our analysis s

32、hows that,compared to the simplest regular 5G device,the techniques in Table 1 can help to reduce the bill-of-materials cost for the simplest RedCap device by about 65 percent in low/mid(FR1)frequency bands and by about 50 percent in high(FR2)frequency bands.Furthermore,the reduction in the number o

33、f receive antenna branches can also help to reduce the physical size of the device.There can be RedCap devices with capabilities in-between those of the simplest and the most advanced RedCap devices.For example,a RedCap device can support two downlink MIMO layers without supporting 256 quadrature am

34、plitude modulation(QAM)in the RedCap-expanding the 5G device ecosystem for consumers and industries Reducing device cost and complexity February 20238downlink.However,a RedCap device cannot support transmit/receive bandwidths larger than 20 MHz for low/mid frequency bands or more than 100 MHz for hi

35、gh frequency bands.Also,it cannot support features and capabilities relating to carrier aggregation,dual connectivity,more than two receive antenna branches,more than two downlink MIMO layers,more than one transmit antenna branch,or more than one uplink MIMO layer.In addition to those techniques lis

36、ted in Table 1,a few optional complexity reduction techniques for the higher layers of the radio protocol stack have also been introduced for RedCap devices.These include a reduction in the maximum number of data radio bearers from 16 to 8,a reduction in sequence number length for packet data conver

37、gence protocols(PDCP)and radio-link control(RLC)layers from 18 bits to 12 bits,and making automatic neighbor relation functionality an optional capability.The higher-layer complexity reduction techniques mentioned in this paragraph are not expected to impact the peak data rate.Low/mid(FR1)frequency

38、bandsHigh(FR2)frequency bandsSimplest regular 5G deviceMost advanced RedCap deviceSimplest RedCap deviceSimplest regular 5G deviceMost advanced RedCap deviceSimplest RedCap deviceMaximum transmit/receive bandwidth100 MHz20 MHz20 MHz200 MHz100 MHz100 MHzSupported number of receive antenna branches an

39、d downlink MIMO layers2 or 4(depending on the frequency band)21222 antenna branches,but only 1 MIMO layerSupported number of transmit antenna branches and uplink MIMO layers Note 1111111 Device power class(PC)PC 3PC 3PC 3PC 3 Note 2 PC 3 Note 2PC 7 Note 3Maximum downlink modulation order256 QAM256 Q

40、AM64 QAM64 QAM256 QAM64 QAMMaximum uplink modulation order Note 164 QAM256 QAM64 QAM64 QAM256 QAM64 QAMDuplex operationTDD or full-duplex FDDTDD or full-duplex FDDTDD or half-duplex FDDTDDTDDTDDTable 1:Comparison of the simplest regular 5G device with the simplest and the most advanced RedCap device

41、.Note 1:This capability has not been relaxed for RedCap UEs.It has been included in the table for the sake of completeness.Note 2:PC 3 in FR2 is associated with handheld devices.Note 3:PC 7 is a lower power class than PC 3,and therefore,it has lower radiated power and lower reference sensitivity req

42、uirements than PC 3.Consequently,RedCap devices supporting PC 7 can be equipped with fewer antenna elements and/or panels than that of devices supporting PC 3.RedCap-expanding the 5G device ecosystem for consumers and industries Reducing device cost and complexity February 20239The complexity reduct

43、ions in Table 1 would impact the achievable peak data rate,and for the simplest RedCap device,the resulting peak data rates in downlink/uplink are approximately:85/90 Mbps in low(FR1 FDD)bands,assuming 15 kHz subcarrier spacing,and that the device supports full-duplex FDD.The peak rates will be lowe

44、r for half-duplex FDD devices as they cannot transmit and receive at the same time.50/35 Mbps in mid(FR1 TDD)bands,assuming 30 kHz subcarrier spacing and a downlink/uplink split of 60/40 percent.240/175 Mbps in high(FR2 TDD)bands,assuming 120 kHz subcarrier spacing and a downlink/uplink split of 60/

45、40 percent.These peak rates are sufficient to fulfill the requirements of most of the intended use cases for RedCap.A more advanced RedCap device can support a higher peak rate,which could be useful for low-end AR/VR use cases.Figure 4 shows a comparison of the maximum achievable peak data rates in

46、different bands for the simplest regular 5G device,the most advanced RedCap device,and the simplest RedCap device.In principle,the devices can support an even lower peak data rate than those shown in Figure 4 by reporting a down-scaled peak rate using so-called peak rate scaling factor.For example,t

47、he RedCap devices are only required to support peak rates in downlink/uplink of approximately 55/60 Mbps(rather than 85/90 Mbps)in FDD bands.Figure 4:Comparison of achievable peak data rates in different bands for the simplest regular 5G device,the most advanced RedCap device,and the simplest RedCap

48、 device.Simplestregular 5Gdevice Most advancedRedCapdeviceFR1 FDD58023022512085901,400190130455035970355645235240175FR1 TDD(with DL/UL split 60%/40%)FR2 TDD(with DL/UL split 60%/40%)SimplestRedCapdeviceSimplestregular 5Gdevice Most advancedRedCapdeviceSimplestRedCapdeviceSimplestregular 5Gdevice Mos

49、t advancedRedCapdeviceSimplestRedCapdeviceDownlinkUplinkMbpsRedCap-expanding the 5G device ecosystem for consumers and industries Addressing diverse battery life requirements February 202310Addressing diverse battery life requirements Some of the targeted RedCap use cases have more stringent require

50、ments on device battery life compared to 5G use cases in general.Also,as described earlier,the different RedCap use cases have different device battery life requirements.Therefore,the solutions for device battery life improvement need to account for such diverse requirements.To meet the requirements

51、,RedCap supports reduced device activities in terms of downlink monitoring and mobility measurements,as outlined below.Extended discontinuous reception mechanism The key to extend battery life is the discontinuous reception(DRX)mechanism.This is a mechanism where a device turns off its receiver circ

52、uitry over periods of time to save power.In 5G,the network can configure a device with DRX cycles that can vary from a few hundred milliseconds to a few seconds(up to 2.56 seconds),depending on the downlink latency requirements.This value range has been extended in Release 17 by introducing eDRX for

53、 RedCap devices.The value range for eDRX cycles is up to about 3 hours for devices in Radio resource control(RRC)Idle mode and 10.24 seconds for devices in RRC Inactive mode.This range is the same as for the existing Massive IoT technology NB-IoT and,therefore,the relative power savings could in pri

54、nciple be as large for RedCap as for NB-IoT.The potential drawback with eDRX is the increased downlink latency since the device cannot respond until the end of the sleep cycle.The device wakes up less frequently when configured with eDRX cycles and is not mandated to monitor paging messages and noti

55、fications during the sleep cycles.However,since RedCap use cases do not have as RedCap-expanding the 5G device ecosystem for consumers and industries Addressing diverse battery life requirements February 202311stringent latency requirements as eMBB or URLLC use cases,latency can potentially be trade

56、d-off for battery life improvement.Furthermore,the device cannot stay in a sleep state when there is data activity in the uplink.Therefore,the more frequent the data transmissions are in the uplink,the smaller the improvements are in battery life.In consequence,the magnitude of improvement in batter

57、y life depends on how often the device has something to transmit in the uplink and how much time the device can spend in a sleep state during the sleep cycles.This is demonstrated in Figure 5 where different average uplink data interarrival times(IATs)are illustrated by different curves and one can

58、observe that improvement in battery life increases with the length of the eDRX sleep cycle for RRC Idle mode.The gain is therefore the biggest for a device with very relaxed downlink latency requirements,such that an eDRX cycle of close to three hours can be configured,and with very infrequent data

59、transmission in the uplink.With the value range considered in these evaluations,the gain is,for example,the largest for a two-hour eDRX cycle with data transmission activity in the uplink on average every three hours,in which case the battery life can be extended by 80 times compared to a non-eDRX c

60、ase.In Release 18,the maximal eDRX cycle length in RRC Inactive will also be extended to about three hours 4 to give a similar gain to that of eDRX in RRC Idle.Figure 5.Device battery life improvement as a function of eDRX sleep cycle length for different data interarrival times(IATs).0.010.11101000

61、10203040506070805 min IAT1 min IAT15 min IAT60 min IAT180 min IATeDRX sleep cycle(minutes)Battery life improvement(by factor of X)RedCap-expanding the 5G device ecosystem for consumers and industries Addressing diverse battery life requirements February 202312RRM measurement relaxation for RedCap de

62、vices To achieve the best performance,both for the device itself and for the network as a whole,it must be ensured that the device connects to the base station with the strongest signal strength.For this reason,devices perform RRM mobility measurements on downlink signals broadcasted by the base sta

63、tion.This consumes energy in the device since the receiver,and sometimes also the transmitter needs to be kept active.One way to extend device battery life is to relax the requirements to allow RedCap devices to perform the measurements less frequently.For this purpose,it is recommended to apply rel

64、axed cell monitoring(also known as relaxed measurements)which allows the device to measure less often based on the operating scenarios.The operating scenarios are characterized by the mobility and the location of the device in the cell.In general,all 5G devices can be operated in different activity

65、states,such as the two low activity states(RRC Idle and RRC Inactive)and the high activity state(RRC Connected).In RRC Idle and RRC Inactive states,the relaxed measurements introduced in Release 16 NR for regular 5G devices allow the device to measure less often or in some cases not to measure at al

66、l on the neighbor cells when the device is operating under limited mobility or when it is not located at the cell border.The relaxed measurements introduced for RedCap in Release 17 allow even further relaxation and supports new relaxation scenarios compared to the Release 16 relaxation.For example,

67、the relaxation factors and period of time to not perform any measurements on neighbor cells are extended,and moreover,relaxation in stationary scenario is introduced for RedCap.This improves the battery life of the RedCap device.Furthermore,eDRX can be configured for a RedCap device in RRC Idle or R

68、RC Inactive states together with relaxed measurements.This enables the device to improve its battery life more than what can be achieved with only RRM measurement relaxation.In RRC Connected state,there is no solution to support relaxed RRM monitoring for regular 5G devices.Solutions are introduced

69、for RedCap to identify low mobility scenarios and report the result to the network.This information serves as a basis for the network to find suitable measurement configurations in the device to achieve further battery life improvements.It is expected that these relaxed measurement methods will enab

70、le the longer device battery life required to serve some of the RedCap use cases.RedCap-expanding the 5G device ecosystem for consumers and industries Network deployment aspects for RedCap devices February 202313Network deployment aspects for RedCap devices It is important that different device type

71、s can co-exist efficiently within the same cells in the same network.There is a potential risk that reducing the bandwidth or number of antennas of the RedCap devices will have undesired impacts both on the performance of the RedCap devices themselves as well as on other(non-RedCap)devices.If desire

72、d,the network can bar access to a cell for all RedCap devices or for a subset of them(specifically,RedCap devices with a single receive antenna branch and/or RedCap devices not supporting full-duplex operations).However,as described in the following subsections,it is generally possible to support ef

73、ficient coexistence between different device types without significant negative impact on the overall network performance.Ensuring good coverage for RedCap devices in an efficient way In a cellular network,it is important to ensure good coverage for all devices.For a device to have good coverage,it

74、needs to be able to receive and transmit multiple data channels and control channels in downlink and uplink.For low-to-mid frequency bands(FR1),since a RedCap device has reduced bandwidth and a reduced number of receive antenna branches,the performance of downlink channels may RedCap-expanding the 5

75、G device ecosystem for consumers and industries Network deployment aspects for RedCap devices February 202314be impacted.However,we expect that the RedCap device will achieve similar coverage as a regular 5G device.The reason is that,even with the reduced capabilities,the performance of downlink cha

76、nnels of a RedCap device is better than the bottleneck(weakest)channel of the regular 5G device.The bottleneck channel determines the coverage of the cell.For a regular 5G device,the bottleneck channel is typically the uplink data channel(PUSCH).Therefore,there may not be a need for redimensioning e

77、xisting 5G networks prior to RedCap deployment.For high frequency bands(FR2),the number of receive antenna branches has not been reduced for the RedCap device.Also,the RedCap device supports a relatively large bandwidth of 100 MHz in FR2.Based on these considerations,the RedCap device is expected to

78、 achieve similar coverage as the regular 5G device.However,as shown in Table 1,the RedCap device can support a lower power class in FR2.This reduces the radiated power requirements in the uplink and the reference sensitivity requirements in the downlink.Therefore,the coverage of some of the uplink a

79、nd downlink channels may be impacted for devices using the lower power class.However,it is expected that the coverage can be recovered using traditional techniques,such as retransmissions for data channels.It is also desired to ensure coverage for RedCap devices without increasing the required radio

80、 resources for downlink transmissions unnecessarily.For the network to efficiently schedule devices with different capabilities,and thus to avoid unnecessarily using many radio resources,there may be a need to identify RedCap devices early on,possibly already in the beginning of the initial-access p

81、rocedure.Therefore,a RedCap device identifies itself as a RedCap device in Message 3 of the random-access procedure(which is part of the initial-access procedure).In addition,there is a possibility for the network to configure a RedCap device to identify itself already in Message 1 of the random-acc

82、ess procedure.Avoiding resource fragmentation and signaling overhead The frequency spectrum is a fundamental resource shared between the users in a cellular network.In every time slot,the base station tries to schedule data transmissions for different users efficiently in the frequency domain to ach

83、ieve both high user throughput and high system capacity.This is true for both downlink and uplink,but uplink scheduling presents an additional challenge since each device may only be able to utilize uplink resource allocations that are contiguous in the frequency domain.Since RedCap devices have a m

84、aximum bandwidth which may be much smaller than the total cell bandwidth,one potential coexistence issue when deploying RedCap devices and regular(non-RedCap)devices in a cell is uplink resource fragmentation.If such resource fragmentation prevents regular devices from utilizing the entire available

85、 bandwidth,they may not be able to transmit the data quickly over a wide contiguous frequency allocation in uplink and are instead forced to transmit in a narrower bandwidth allocation over a more extended period.This may result in a significant uplink peak data rate reduction for those regular devi

86、ces.Therefore,we want to highlight two mechanisms that have been standardized to minimize fragmentation of uplink resources for regular 5G NR devices due to transmission from RedCap devices.These mechanisms are described below and illustrated in Figure 6.First,the network can configure a RedCap-spec

87、ific initial bandwidth part(BWP)separate from the initial BWP used by regular devices.This RedCap-specific initial BWP can be RedCap-expanding the 5G device ecosystem for consumers and industries Network deployment aspects for RedCap devices February 202315placed near the edge of the uplink frequenc

88、y resource to free up contiguous resources in the center for regular devices.Since the RedCap-specific initial BWP is primarily intended to be used only briefly during initial access,it can be configured without the ordinary periodic downlink transmissions of synchronization signals and system infor

89、mation,thus avoiding additional signaling overhead.Second,the network can disable frequency hopping for all transmissions from RedCap devices to further reduce the uplink resource fragmentation.In regular 5G NR,many transmissions can be carried out using frequency hopping to improve the probability

90、of successful reception in case of imperfect propagation conditions.However,when a transmission hops between different frequencies,it may contribute to undesired resource fragmentation,so it may be a good idea to deactivate the frequency hopping when it is not needed.In regular 5G NR,the frequency h

91、opping can be deactivated for all transmissions except for one,but for RedCap devices the frequency hopping can also be deactivated for this transmission(to be specific,a transmission of a 1-bit acknowledgment on the so-called physical uplink control channel(PUCCH)during the initial access procedure

92、)to minimize uplink resource fragmentation.Ensuring high network capacity and cell spectral efficiency Because of the device complexity reductions,RedCap link performance will inevitably be reduced.With many RedCap users in the network,there may be a concern that this could indirectly lead to worse

93、performance for non-RedCap and negatively impact,for example,eMBB performance.Therefore,we have run system level simulations to study the impact based on the evaluation assumptions agreed by 3GPP(see details and further results in 5).In the uplink,we found that the presence of RedCap users does not

94、have any noticeable impact on the eMBB user throughput and performance.For the downlink,RedCap devices with 1 receive antenna branch would have the largest impact,and in Figure 7 the median eMBB user throughput is shown for an increasing fraction of such RedCap users(note that unlike the user throug

95、hput,the cell throughput is averaged over time also when there is nothing to transmit).e.g.,20 MHzRegular initial BWPincluding synchronization signals and system informationRedCap-specificinitial BWPPUCCHPUCCHPUCCHe.g.,100 MHzFull carrier bandwidth,e.g.,100 MHzFigure 6:Illustration of mechanisms for

96、 avoiding resource fragmentation and signaling overhead.Separate initial bandwidth parts (BWPs)can be configured for regular devices and RedCap devices.The RedCap-specific initial BWP can be configured near the carrier edge to avoid resource fragmentation.The RedCap-specific initial BWP does not nee

97、d to include synchronization signals and system information.Frequency hopping can be disabled for all uplink transmissions (including PUCCH)to further avoid resource fragmentation.RedCap-expanding the 5G device ecosystem for consumers and industries Network deployment aspects for RedCap devices Febr

98、uary 202316Figure 7:Impact on eMBB user throughput from an increasing fraction of RedCap users.As can be seen from the results in Figure 7,at low average cell load no impact on the eMBB user throughput can be seen.At higher load,a slight degeneration of the eMBB performance can be noted but only for

99、 a fraction of 50 percent or more of RedCap users with 1 receive antenna branch.For eMBB users in bad coverage(fifth percentile)the tendency is the same,and for eMBB users in good coverage(95th percentile),no impact at all from an increasing RedCap user fraction can be noticed.The conclusion from th

100、ese simulations is therefore that in realistic cases where most users are not of RedCap type with 1 receive antenna branch and the load is not high,there will in practice be no noticeable impact on eMBB performance.0%RedCap10%RedCap25%RedCap50%RedCap75%RedCap450500550600650700750800850Median eMBB us

101、er throughput MbpsAverage traffic per cell MbpsDL throughput for 1 Rx RedCap050100150200250RedCap-expanding the 5G device ecosystem for consumers and industries Further evolution and LTE-to-NR migration for IoT use cases February 202317Further evolution and LTE-to-NR migration for IoT use cases As m

102、entioned above,the RedCap devices introduced in Release 17 have similar peak rates and complexity as existing low-end LTE device categories(for example,Cat-2,Cat-3,or Cat-4).This makes RedCap devices ideal for replacing low-end LTE devices when use cases today served by low-end LTE devices eventuall

103、y need to be migrated to NR.The device hardware requirements(in terms of bandwidth,number of antennas,supported modulation,and so on)are similar to low-end LTE devices,which facilitates implementation of dual-mode devices supporting both a low-end LTE device category and a RedCap device type if need

104、ed.Furthermore,for IoT use cases with even lower peak rate requirements,a new RedCap device type will be introduced in Release 18 with a peak rate target of about 10 Mbps 4,which is comparable to the peak rate for the lowest ordinary LTE device categories(that is,Cat-1 and its single-antenna variant

105、 Cat-1bis).However,it is expected that the additional complexity reduction compared to the simplest Release 17 RedCap device will be relatively small(less than 10 percent).For a comparison between 4G and 5G device types,see Figure 1.Moreover,accurate positioning for location services is crucial for

106、many IoT use cases.Basic positioning is supported for RedCap devices already in Release 17,but Release 18 RedCap-expanding the 5G device ecosystem for consumers and industries Further evolution and LTE-to-NR migration for IoT use cases February 202318introduces improved positioning support for RedCa

107、p devices,adjusting for their reduced capabilities.Since 5G NR supports a wider range of frequency bands and deployment options compared to LTE/LTE-M/NB-IoT,it can be expected that RedCap devices can enable IoT use cases in new scenarios.For example,it may be desired to support Massive IoT use cases

108、 in frequency bands where LTE-M/NB-IoT either has no standard support or no product ecosystem(for example,in mid/high TDD bands),and in such cases we envision RedCap to be able to serve as a substitute for LTE-M/NB-IoT.From a network point of view,support for RedCap devices can be expected to be int

109、roduced as a software upgrade of the network,that is,without the need for any new hardware deployments.It should be noted that RedCap supports the same spectrum sharing techniques 6 as normal NR,meaning that different device types(LTE,LTE-M,NB-IoT,NR,RedCap)can be supported on the same cell carrier

110、if desired.RedCap-expanding the 5G device ecosystem for consumers and industries ConclusionFebruary 202319ConclusionThe introduction of RedCap devices in Release 17 is expected to expand the 5G device ecosystem by introducing new devices with lower cost/complexity,smaller size,and longer battery lif

111、e than regular 5G NR devices.For many IoT use cases,which are not high-end,NR devices are overly capable,and they may not be cost-efficient for such use cases.RedCap,which belongs to the Broadband IoT category,is introduced to match this market segment.Important use cases envisioned for RedCap inclu

112、de wearables,industrial wireless sensors,video surveillance cameras,and low-end AR/VR applications.Moreover,RedCap devices are ideal for replacing low-end LTE devices when use cases today served by low-end LTE devices eventually need to be migrated to NR.RedCap can also serve as a substitute for LTE

113、-M/NB-IoT in frequency bands where they have no standard support or no product ecosystem(for example,in mid/high TDD bands).Further device simplifications for RedCap are expected in Release 18 to provide improved support for Release 17 use cases,and support expansion into new segments of use cases.H

114、owever,the further cost/complexity reduction in Release 18 is expected to be small compared to Release 17.As described in this white paper,it is possible for a RedCap device to efficiently co-exist with other NR device types without significant negative impact on the overall network performance.Furt

115、hermore,RedCap inherits many of the key benefits of 5G NR such as support for a wide range of frequency bands(including millimeter-wave bands)and deployment options,native 5G core network,high network energy efficiency due to lean NR design,low latency,beam-based air interface,and so on.To summarize

116、,RedCap expands the 5G device ecosystem for consumers and industries in ways that are attractive both from device and network points of view.RedCap-expanding the 5G device ecosystem for consumers and industries GlossaryFebruary 202320Glossary3GPP 3rd Generation Partnership Project BWP Bandwidth part

117、DL DownlinkDRX Discontinuous receptioneDRX Extended discontinuous receptioneMBB Enhanced mobile broadbandFDD Frequency-division duplexingFR1 Frequency range 1(410 7,125 MHz)FR2 Frequency range 2(24,250 52,600 MHz)IoT Internet of thingsLTE Long-term evolutionMIMO Multiple-input multiple-outputmMTC Ma

118、ssive machine-type communicationsNR New radioPC Power classPUCCH Physical uplink control channelQAM Quadrature amplitude modulationRedCap Reduced capabilityRRC Radio resource control RRM Radio resource managementTDD Time-division duplexingUL UplinkURLLC Ultra-reliable low-latency communicationsRedCa

119、p-expanding the 5G device ecosystem for consumers and industries ReferencesFebruary 202321References1.Ericsson Mobility Report November 2022,Broadband IoT(4G/5G)connections to dominate by end of 2028,page 11.2.RP-220966,“Revised WID on support of reduced capability NR devices”,Ericsson,3GPP TSG RAN

120、Meeting#95e,March 2022.3.Gartner Forecasts Global Spending on Wearable Devices to Total$81.5 Billion in 2021,January 2021.4.RP-223544,“Revised WID on Enhanced support of reduced capability NR devices”,Ericsson,3GPP TSG RAN#98-e,December 2022.5.TR 38.875,“Study on Support of Reduced Capability NR Dev

121、ices(Release 17),”March 2021.6.Sharing for the best performance,stay ahead of the game with Ericsson Spectrum Sharing.RedCap-expanding the 5G device ecosystem for consumers and industries AuthorsFebruary 202322AuthorsSandeep Narayanan Kadan Veedu is a Senior Researcher with Ericsson Research,Stockho

122、lm,Sweden,where he is involved in the research and standardization of cellular IoT.He is also a standardization delegate for Ericsson in 3GPP.Prior to joining Ericsson in 2018,he was a research associate at Kings College London,UK.He has also held various research positions with University College D

123、ublin,Ireland,Northwestern University,US,and the University of Edinburgh,UK.He has a Ph.D.degree in electrical and information engineering from the University of LAquila,Italy.Mohammad Mozaffari is a Senior Researcher at Ericsson Research,Silicon Valley,US.He received his Ph.D.degree in electrical a

124、nd computer engineering from Virginia Tech in 2018.His research interests span diverse areas,including 5G and 6G wireless networks,UAV and drone communications,IoT,and machine learning.He has been actively contributing to 3GPP standardization for NB-IoT,LTE-MTC,RedCap,and wake-up radio.He is the rec

125、ipient of the IEEE ComSoc Young Author Best Paper Award and Outstanding Ph.D.Dissertation Award.He is currently an associate editor of the IEEE Vehicular Technology Magazine and the IEEE Transactions on Machine Learning in Communications and Networking.RedCap-expanding the 5G device ecosystem for co

126、nsumers and industries AuthorsFebruary 202323Andreas Hglund has a Master of Science in engineering physics(2002)and a Ph.D.in condensed matter physics from Uppsala University(2007).He is a master researcher at Ericsson Research and since joining in 2008,he has worked on HSPA,LTE,system simulations,5

127、G research in the METIS project,3GPP standardization of LTE MTC(Cat-M1)and NB-IoT.He is currently working with 3GPP Rel-17 RedCap and small data transmission(SDT),Rel-18 Wake-up Receiver,eRedCap,MT-SDT,as well as IoT research for 6G.Santhan Thangarasa is a Senior Specialist at Ericsson Research.His

128、prime area of expertise is radio resource management requirements for IoT technologies.He received his Master of Science in information and communication engineering from the Royal Institute of Technology(KTH)in Sweden.He has more than 10 years of research experience and has served as RRM rapporteur

129、,moderator,and editor of the 3GPP TSG RAN Work Items on LTE-MTC work in Releases 13 to 17 and in NR RedCap in Release 17 in 3GPP TSG RAN WG4.He is also the rapporteur for the 3GPP Technical Specification for UE requirements for RRM(TS 36.133).RedCap-expanding the 5G device ecosystem for consumers an

130、d industries AuthorsFebruary 202324Emre A.Yavuz received his B.Sc.and M.Sc.degrees in Electrical&Electronics Engineering at METU in Turkey.He received his Ph.D.degree in Electrical&Computer Engineering at UBC in Canada.He worked as a consultant in Vancouver prior to joining the School of Electrical

131、Engineering at KTH in Stockholm,as a post-doctoral fellow.He is a Master Researcher at Ericsson Business Unit Networks,working with 4G/5G Layer 2/3 standardization in 3GPP TSG RAN WG2 leading the technical work to standardize LTE MTC and NB-IoT in Releases 13 to 17,NR RedCap,and NR and IoT NTN(Non-T

132、errestrial Networks)in Release 17.Johan Bergman is a Master Researcher at Ericsson Business Unit Networks.He received his masters degree in engineering physics from Chalmers University of Technology in Sweden.He joined Ericsson in 1997,and since 2005 he has been working with 3G/4G/5G physical layer

133、standardization in 3GPP TSG RAN Working Group 1.As rapporteur of the 3GPP TSG RAN Work Items on LTE-MTC in Releases 13 to 16 and NR RedCap in Releases 17 and 18,he has led the technical work to standardize new features dedicated to IoT.He was a corecipient of Ericssons Inventor of the Year award for 2017.