TOP CONSIDERATIONS. for 5G New Radio Device Designers

Transcription

1 TOP CONSIDERATIONS for 5G New Radio Device Designers

2 Introduction 5G New Radio (NR) is rapidly approaching. The new physical layer standards define a flexible air interface to support the many use cases expected in 5G, and your designs for devices like smartphones, tablets, laptops, and wearables will need to operate in new spectrum and with new technologies. This all means more complexity and greater design challenges. This ebook outlines the challenges you ll face tackling issues such as new frequency spectrum and wider bandwidths, MIMO (multiple input, multiple output) and beam steering, over-the air (OTA) testing, and 5G NR coexistence with other wireless communications systems. You ll want to stay ahead of this rapidly evolving environment so you can accelerate your device designs as 5G standards evolve.

3 Contents 5 Considerations for 5G Device Designers Understanding 5G NR Specifications Extending into mmwave Spectrum MIMO and Beam Steering mmwave Over-the-Air (OTA) Measurements New standards introduce more test scenarios and challenge traditional design and test methodologies To achieve ultra-fast download rates, your designs will need to include operation in mmwave frequency bands MIMO and beam steering are key enabling technologies you will need to implement to maximize connection quality and throughput Highly integrated mmwave antennas demand that you move beyond cabled connection tests Coexistence Your 5G designs will need to operate flawlessly in spectrum with competing signals and other devices

4 CHAPTER 1 Understanding 5G NR Specifications 5G NR specifications enable much greater flexibility in wireless communication systems, but will require you to change the way you design and test 5G devices. UNDERSTANDING 5G NR Top Considerations for 5G New Radio Device Designers 4

5 CHAPTER 1 Understanding 5G NR Specifications Enhanced Broadband Gigabytes In a Second 3D Video, UHD Screens Smart Home Building Smart City Voice Work and Play in the Cloud Augmented Reality Industry Automation Mission Critical Applications Self Driving Cars Massive Machine Type Communications Figure 1: Source ITU 5G Recommendations 9/2015 Ultra-Reliable and Low Latency Communications The vision for 5G focuses on three primary use cases: enhanced mobile broadband (embb), ultra-reliable and low latency communications (URLLC), and massive machine-type communications (mmtc). These use cases will enable vast improvements in the cellular network to support many new services. Your success depends on designing a quality, cost-effective design in a timely fashion. The initial 5G NR release 15 (December 2017) introduced non-standalone mode (NSA), where the 5G network relies on an existing 4G network for the control plane. In June 2018, support for standalone mode (SA) expanded the standard to allow a 5G base station (or gnb) to act as a master node in the network without relying on an existing 4G network for control. As a 5G designer, you need to ensure that your designs will work with and alongside the 4G network. The 5G NR specifications lay the foundation for the flexible structure needed to support the many different use cases. Your 5G designs will need to support the key features covered in this chapter. UNDERSTANDING 5G NR Top Considerations for 5G New Radio Device Designers 5

6 Scalable Numerology Scalable Numerology offers flexible allocation of resources to support many different services across diverse frequency bands. Scalable sub-carrier spacing has an inverse relationship with symbol time. This enables variable slot duration to support different applications such as high throughput mmwave operation, high latency IoT services, or low-latency no-fail applications. Time-bound resources can now scale and be assigned using smaller mini-slot units where transmission can start immediately without waiting for slot boundaries, enabling quick delivery of low latency payloads. The Challenge: Scalable numerology makes the air interface more complex, increasing the required test permutations and potential for design flaws. 1ms subframe aligned with LTE CP-OFDM symbol Subframe 15 khz khz 500 µs slot Mini- Slot 60 khz 250 µs slot 120 khz 125 µs slot Figure 2: Subframe, slot, and mini-slot structure as a function of subcarrier spacing UNDERSTANDING 5G NR Top Considerations for 5G New Radio Device Designers 6

7 Waveforms Waveforms have not changed a great deal from 4G except for in the uplink (UL). CP-OFDM (Cyclic Prefix-Orthogonal Frequency Division Multiplexing) was used in 4G LTE downlink (DL), but usage has now expanded to support both downlink and uplink. Greater UL modulation density up to 256 QAM versus 64 QAM in LTE-Advanced release 13 means more data can be sent in the waveform. 5G NR adds an optional single carrier modulation technique DFT-s-OFDM (Discrete Fourier Transform spread OFDM) in the UL, which offers better power efficiency than CP-OFDM and is especially useful for low-power IoT use cases. The Challenge: Introducing CP-OFDM in the UL and use of higher order modulation in the device means you need to design and test with much higher performance than ever before. Frequency Ranges Maximum Carrier Bandwidth Sub Carrier Spacing Maximum number of Subcarriers Carrier Aggregation Frequency Range (FR) 1: 450 MHz - 6 GHz Frequency Range (FR) 2: GHz FR1: Up to 100 MHz FR2: Up to 400 MHz FR1: 15 khz, 30 khz, 60 khz FR2: 60 khz, 120 khz, 240 khz 3300 (up to 4096 FFTs, Fast Fourier Transform) Up to 16 carriers Modulation CP-OFDM (UL/DL): QPSK, 16QAM, 64QAM and 256QAM DFT-s-OFDM (UL): π/2-bpsk, 16QAM, 64QAM and 256QAM MIMO 8x8 MIMO Up to 8 layers in downlink, up to 4 layers in the uplink Figure 3: 5G NR waveforms require new levels of performance in devices UNDERSTANDING 5G NR Top Considerations for 5G New Radio Device Designers 7

8 Initial Access Procedures Initial Access Procedures have changed due to the use of mmwave beam steering. Beam steering is considered essential for mmwave communications due to the high channel losses that must be overcome. 5G NR identifies new initial access procedures that use beam sweeping from the base station to find the user equipment (UE). UE devices need to monitor and select the strongest beam from the base station and perform handoffs and fall back procedures as the UE travels through the network. The Challenge: As a device designer, you now need to validate that the UE can find the beams from the base station, establish the communication link, and perform data transfers and beam management functions as the device travels through the network. UNDERSTANDING 5G NR Top Considerations for 5G New Radio Device Designers 8

9 Bandwidth Parts (BWP) Bandwidth Parts (BWP) are new in 5G NR. In LTE, all UEs were required to transmit and receive within the cell s full bandwidth. This is no longer the case in 5G NR. A cell s bandwidth can be sub-divided and spectrum can be allocated for different services in a device. Each bandwidth part (BWP) can have its own numerology, meaning each BWP can be configured differently with its own signal characteristic, enabling more efficient use of the spectrum. This feature is good for integrating signals that may have reduced energy requirements, or different functions or services, or for providing coexistence with other systems. The Challenge: Bandwidth parts enable better use of the spectrum but also introduce more test cases that need to be validated in a device into the full bandwidth. LEARN MORE ABOUT THE 5G NR STANDARDS White Paper: First Steps in 5G: Overcoming New Radio Device Challenges Series Webinar: Understanding 5G NR Physical Layer Webinar: Completing Rel-15 of 5G NR Physical Layer Figure 4: Analyzing a 5G NR signal with different numerologies is essential to validating device performance UNDERSTANDING 5G NR Top Considerations for 5G New Radio Device Designers 9

10 CHAPTER 2 Extending into mmwave Spectrum Spectrum is at the heart of 5G s ultra-fast download rates. For wireless communications, this means extending designs into mmwave frequency bands. MMWAVE SPECTRUM Top Considerations for 5G New Radio Device Designers 10

11 CHAPTER 2 Extending into mmwave Spectrum 5G NR introduces new ways to use spectrum in sub-6 GHz and mmwave frequencies. Sub-6 GHz will be the primary access channel and focus new capabilities on extended coverage and support for many low data rate IoT applications and low latency applications like autonomous driving automobiles. Specific 5G NR features including flexible numerology and mini slots can provide very fast response times needed for these low latency applications. mmwave frequencies offer wider channel bandwidths to support embb use cases, enabling data hungry applications like streaming of ultra-high definition 4K or 8K movies. 5G NR reallocates some of the existing LTE bands and adds new licensed and unlicensed spectrum in several bands. mmwave spectrum will be needed to meet 5G peak data rate goals of 20 Gbps in downlink (DL) and 10 Gbps in uplink (UL). 0.6 GHz I S M ISM ISM 24 GHz 2.5 GHz GHz GHz 24 GHz 28 GHz 39 GHz 64-71GHz 71-76GHz Frequency Range 1: 400 MHz to 6 GHz Frequency Range 2: to 52.6 GHz Adds 1.5 GHz of new spectrum in frequency bands n77: GHz n78: GHz n79: GHz Adds 8.25 GHz of new spectrum in frequency bands n257: GHz n258: GHz n260: GHz Frequencies up to 90 GHz are currently being investigated for future releases. MMWAVE SPECTRUM Top Considerations for 5G New Radio Device Designers 11

12 The Challenges One of the most challenging aspects of 5G will be creating designs optimized for mmwave spectrum. Signal impairments such as IQ impairments, phase noise, linear/non-linear compression, and frequency error increase with higher frequency and bandwidth. These impairments can distort the modulated signal, making it difficult for the receiver to accurately demodulate the signal. Another challenge is the usage of higher order modulations in 5G waveforms. To sustain performance, devices must meet tighter error vector magnitude (EVM) specifications specified by the 5G standard, as shown in the table below. Modulation scheme for PDSCH Required EVM Tips for overcoming mmwave wideband signal quality issues: Evaluate signal modulation properties by viewing the IQ constellation to identify potential waveform distortion errors. Identify signal performance issues by measuring overall EVM, EVM per symbol, and EVM per subcarrier. Verify wideband spectrum performance with transmitted power, occupied bandwidth (OBW), adjacent channel power ratio (ACPR), spectrum emissions masks (SEM), and spurious emissions measurements. Ensure test solutions have better performance than the device being measured and use system level calibration with measurement plane at the device under test (DUT). QPSK 17.5 % 16QAM 12.5 % 64QAM 8 % 256QAM 3.5 % LEARN MORE White Paper: First Steps in 5G: Overcoming New Radio Device Challenges Series Solution Brochure: 5G Waveform Generation and Analysis Testbed, Reference Solution Figure 5: 3GPP TS EVM requirements for different 5G modulation schemes Signal performance will be more critical than ever to meet 5G mmwave component and device design specifications. Key performance indicators such as EVM for 256QAM are much more difficult to achieve, and your test solutions must have higher levels of fidelity to measure, validate, and troubleshoot device performance at mmwave frequencies. MMWAVE SPECTRUM Top Considerations for 5G New Radio Device Designers 12

13 CHAPTER 3 MIMO and Beam Steering MIMO and beam steering are key enabling technologies for 5G operation at sub-6 GHz and into mmwave frequency bands. MIMO & BEAM STEERING Top Considerations for 5G New Radio Device Designers 13

14 CHAPTER 3 MIMO and Beam Steering MIMO and beam steering techniques will enable more capacity on the network and higher data throughput, and will help overcome signal propagation issues that increase with frequency. Beam steering and beamforming utilize multiple antenna elements to create directional high-gain beams, which are used to overcome the additional path loss that is especially prevalent at mmwave frequencies. Beam steering is like pointing a small beam at a specific user verses blanketing the area with a flood light. Both the base station and the mobile device will need positional awareness and will need to direct beams towards each other to maintain a highquality link. gnb Synchronization and broadcast signals (beam sweeping) Figure 6: Beam sweeping is the technique used to broadcast signals from the base station so UEs can find the strongest beam and establish a communication link gnb Beam acquisition for UE UE Downlink Beam Uplink Beam MIMO & BEAM STEERING Top Considerations for 5G New Radio Device Designers 14

15 The Challenges To achieve desired performance levels, device manufactures will need to implement and test multi-element antenna technologies in multiple frequency bands from sub-6 GHz to mmwave frequencies. It is crucial to characterize device antenna patterns to ensure proper antenna gain, side lobes and null depth to maximize the radiated efficiency of the signal. The method for acquiring a signal has changed significantly in 5G, since neither the device nor the base station knows the direction of the other end of the link. 5G NR defines new initial access and attach procedures to establish a link. Beam management tests are a significant new area of test that must be addressed during device design, adding more complexity to your 5G device test plan. Tips for overcoming MIMO and beam steering challenges: Verify an antenna s 3D beam performance early in the development cycle with system level simulation before moving to hardware. Once your design is in hardware, verify a beam s performance and RF characteristics with EVM and ACPR measurements over the antenna scan to determine how much the beam characteristics changes with movement. This should be done using a calibrated OTA test method with 5G NR compliant waveform generation and 3D analysis tools. Use a network emulator to test the protocol early in the development cycle to ensure the device s ability to connect to the network and perform initial access and beam management tasks like handovers and 4G fallback procedures. Add a channel emulator to evaluate end-to-end performance with real-world impairments like excessive path loss or multi-path fading. LEARN MORE Webcast: mmwave 5G Phased Array and Beamforming System Design Application Note: Testing 5G: Data Throughput White Paper: OTA Setup for 5G Beamforming Functional Test Solution Brief: 5G Protocol R&D Toolset MIMO & BEAM STEERING Top Considerations for 5G New Radio Device Designers 15

16 CHAPTER 4 mmwave Over-the-Air (OTA) Tests As mmwave adoption increases, new test techniques are required. Antenna arrays are increasingly being integrated into RFICs, making it difficult, if not impossible, to test with a cabled connection. MMWAVE OTA Top Considerations for 5G New Radio Device Designers 16

17 CHAPTER 4 mmwave Over-the-Air (OTA) Tests Beam Antenna Beam Current sub-6 GHz RF performance tests are mostly done using cabled connections. mmwave requires more over the air (OTA) testing for several reasons. 5G smartphones will have GPS, Wi-Fi, Bluetooth, and multiple antennas to support cellular, and co-existence becomes exponentially more difficult with multiple antennas in close proximity. Designs with antennas bonded onto the RFICs will be common in 5G UE devices, but difficult to probe. Cabled tests are also insufficient for testing parameters such as 3D radiated beam size and direction. As a result, OTA tests are needed to characterize and validate radiated beam performance from your device. Antenna Beam Antenna Figure 7: Prototype 5G smartphone with antenna arrays located around the perimeter of the enclosure MMWAVE OTA Top Considerations for 5G New Radio Device Designers 17

18 The Challenges OTA testing is typically performed in the near-field or far-field region from the device. Shown in the table, as the frequency goes higher, the far-field distance and path loss increase as well. A device with a 15-cm radiating diameter, operating at 28 GHz, results in a far-field distance of 4.2 meters and a path loss of 73 db. Due to the higher operating frequency, a traditional far-field test method would result in an excessively large far-field test chamber with path loss that is too great to make accurate and repeatable OTA measurements. Direct far-field, indirect far-field, and near-field scanning test methods are being studied by test vendors and 3GPP to specify suitable OTA test methods. You can leverage Keysight s early involvement in these studies to reduce the time and rework as you scope out your first 5G OTA testbeds. Size D (cm) GHz Distance (m) Path Loss (db) 0.13 m 21 db 0.30m 28 db 0.53 m 33 db 28 GHz Distance (m) Path Loss (db) 1.87 m 66 db 4.2 m 73 db 7.4 m 78 db 43 GHz Distance (m) Path Loss (db) 2.87 m 74 db 6.4 m 81 db 11.4 m 86 db Figure 8: Far-field test distance and resulting path loss for making OTA measurements Tips for overcoming OTA testing challenges: At higher mmwave frequencies, consider an indirect far-field (IFF) test method based on a compact antenna test range (CATR) that is now permitted for RF performance tests by 3GPP. This OTA test method can perform measurements such as transmitted power, transmit signal quality, and spurious emissions for a radiated transmitter with much less path loss than a traditional far-field test chamber. Include a network emulator combined with a channel emulator to characterize the end-to-end full stack data throughput with real-world channel conditions. Partner with Keysight to gain insights into the progress of the specifications and test methods being recommended and approved by 3GPP. MMWAVE OTA Top Considerations for 5G New Radio Device Designers 18

19 Figure 9: Position control and and plotting software enables path loss calibration and 2D/3D plotting Keysight over-the-air test solutions include chambers, probing, and the test equipment used to address a wide range of RF, demodulation, and functional performance tests requirements from RF to mmwave. LEARN MORE White Paper: First Steps in 5G: Overcoming New Radio Device Challenges Series White Paper: OTA Test for Millimeter-Wave 5G NR Devices and Systems MMWAVE OTA Top Considerations for 5G New Radio Device Designers 19

20 CHAPTER 5 Coexistence Adding 5G to an already crowded and congested spectrum increases the potential for coexistence interference. COEXISTENCE Top Considerations for 5G New Radio Device Designers 20

21 EXPLORATION LAND LAND METEOROLOGICAL METEOROLOGICAL This chart is a graphic single-point-in-time portrayal of the Table of Frequency Allocations used by the FCC and NTIA. As such, it may not completely reflect all aspects, i.e. footnotes and recent changes made to the Table of Frequency Allocations. Therefore, for complete information, users should consult the Table to determine the current status of U.S. allocations. For sale by the Superintendent of Documents, U.S. Government Printing Office Internet: bookstore.gpo.gov Phone toll free (866) ; Washington, DC area (202) Facsimile: (202) Mail: Stop SSOP, Washington, DC DETERMINATION OPERATION STANDARD FREQUENCY AND TIME SIGNAL STANDARD FREQUENCY AND TIME SIGNAL Aeronautical Radionavigation (radiobeacons) (radiobeacons) explorationsatellite Standard Frequency and Time Signal Satellite (space-to-) except aeronautical 31.8 mobile THIS CHART WAS CREATED BY DELMON C. MORRISON JUNE 1, 2011 * EXCEPT (R) ** EXCEPT (S-E) (S-E) (S-E) (E-S) (E-S) EXPL 3.65 (E-S) (S-E) (E-S) (E-S) (E-S) 34.2 (radiobeacons) (space-to-) 35.5 Radio location Space research Aeronautical Radionavigation 4.65 ISM ±.02 MHz Meteorological Satellite (space-to-) satellite (-to-space) (space-to-) (space-to-) 4.5 (TELEVISION) 4.7 LAND - (space-to-) Fixed - (space-to-) - (space-to-) (TELEVISION) except aeronautical mobile explorationsatellite explorationsatellite (TELEVISION) explorationsatellite explorationsatellite 58.2 (TELEVISION ) explorationsatellite ISM 5.8 ±.075 GHz except aeronautical mobile (R) (AM ) (TELEVISION) except aeronautical mobile (R) (FM ) ISM ±.015 MHz ISM ±.007 MHz ISM ±.163 MHz AIDS 65.0 ISM ± 0.25 GHz NAVIGATION- - (space-to- ) (space-to- ) Space research (space-to- ) ISM ±.13 MHz (space-to-) Amateur (space-to-) Amateur Amateur-satellite (space-to-) Amateur-satellite Amateur- (space-to-) Amateur satellite 7.45 (-to-space) - - (-to-space) Space research (space-to-) (-to-space) exploration - satellite METEOROLOGICAL- Space research - - Amateur explorationsatellite explorationsatellite - - NAVIGATION NAVIGATION - NAVIGATION- exploration - satellite Space research EXPLORATION Fixed exploration - satellite Space research EXPLORATION EXPLORATION - exploration - satellite Space research ISM ± GHz - Space research (-to-space) Space research Radio - location Standard frequency and time signal satellite (-to-space) Amateur Space (space-to-) - - NAVIGATION Radio astronomy (space-to-) explorationsatellite Space research (-to-space) (space-to-space) (-to-space) (space-to-space) (line of sight only) (ling of sight only including aeronautical 2107 telemetry, but excluding flight testing of manned aircraft) OPERATION (space-to-) (space-to-space) (space-to-) (space-to-space) (space-to-) (space-to-space) 20.2 Standard frequency and time signal satellite (space-to- ) ** 2194 (TELEVISION) Fixed except aeronautical mobile mobile exploration - satellite ISM ±.50 MHz (Passive) (Passive) PLEASE NOTE: THE SPACING ALLOTTED THE SERVICES IN THE SPECTRUM SEGMENTS SHOWN IS NOT PROPORTIONAL TO THE ACTUAL AMOUNT OF SPECTRUM OCCUPIED. explorationsatellite 2505 ** Radio astronomy except aeronautical mobile EXPLORATION - (space-to-) (space-to-) 28.0 Inter-satellite Standard frequency and time signal satellite (-to-space) ISM ± (space-to-) - NAVIGATION- - ISM ± 1 GHz AIDS NAVIGATION CHAPTER 5 Coexistence United States Frequency Allocation - The Radio Spectrum Fixed NOT ALLOCATED STANDARD FREQUENCY AND TIME SIGNAL (20 khz) STANDARD FREQUENCY AND TIME SIGNAL (60 khz) Aeronautical Aeronautical Maritime Radionavigation (radiobeacons) Aeronautical Radionavigation (radiobeacons) (radiobeacons) 0 khz 300 khz To fulfill the promises of 5G, devices need to operate in many different frequency bands and with many different operating models. The combination of 4G and 5G networks will be crucial for devices to maintain coverage while roaming. Devices will require multiple radios that need to operate adjacent to existing cellular bands, and in some cases, in the same spectrum as other wireless communications systems. (radiobeacons) Aeronautical Maritime Radionavigation (radiobeacons) Aeronautical Aeronautical Maritime (distress and calling) (radiobeacons) (ships only) (radiobeacons) Non-Federal Travelers Information Stations (TIS), a mobile service, are authorized in the khz band. Federal TIS operates at 1610 khz. 300 khz 3 MHz (R) (OR) 3MHz LAND except aeronautical mobile (R) LAND (R) LAND LAND Radio astronomy LAND LAND LAND except aeronautical mobile (R) (R) LAND (OR) except aeronautical mobile (R) LAND STANDARD FREQUENCY AND TIME SIGNAL (5 MHz) (R) (OR) except aeronautical mobile (R) (R) (OR) except aeronautical mobile (R) (R) (OR) STANDARD FREQUENCY AND TIME SIGNAL (10 MHz) (R) (OR) (R) (OR) (R) (R) except aeronautical mobile (R) (R) except aeronautical mobile (R) except aeronautical mobile (R) STANDARD FREQUENCY AND TIME SIGNAL (15 MHz) (OR) MET. (space-to-) MET. (space-to-) MET. (space-to-) MET. (space-to-) (R) (R) (R) - OPERATION (space-to-) (space-to-) (space-to-) -satellite OPERATION (space-to-) (space-to-) (space-to-) - OPERATION (space-to-) (space-to-) (space-to-) -satellite OPERATION (space-to-) (space-to-) (space-to-) (-to-space) - (-to-space) LAND LAND (R) (OR) STANDARD FREQUENCY AND TIME SIGNAL (20 MHz) LAND (distress, urgency, safety and calling) except aeronautical mobile LAND LAND except aeronautical mobile (AIS) except aeronautical mobile except aeronautical mobile (R) (AIS) (telephony) (distress and calling) except aeronautical mobile (R) (OR) except aeronautical mobile Land mobile (telephony) STANDARD FREQ. AND TIME SIGNAL (25 MHz) LAND LAND except aeronautical mobile LAND except aeronautical mobile Fixed Land mobile except aeronautical Amateur except aeronautical mobile Land mobile except aeronautical mobile Fixed STANDARD FREQ. AND TIME SIGNAL (2500kHz) LAND except aeronautical mobile except aeronautical mobile LAND LAND (R) 30 MHz Shared spectrum is a proven and viable way to extend the performance and throughput of a device, in particular, harnessing unlicensed spectrum to boost performance using channel aggregation. 5G will utilize shared spectrum in sub-6 GHz and in mmwave frequencies where a device must coexist with other wireless communications systems such as satellite and radar. 30 MHz 300 MHz MHz 3GHz - (-to-space) - (-to-space) 3 GHz 30GHz (-to-space) STANDARD FREQUECY AND TIME SIGNAL - (400.1 MHz) Amateur EXPLORATION - SATTELLITE (deep space) (space-to-) (ground based) MET. SAT. Space Opn. RES. MET. AIDS (Radiosonde) SAT (S-E) - (space-to-) (ground based) Expl Sat Met-Satellite MET-SAT. OPN. MET. AIDS (Radiosonde) SAT. (E-S) - (space-to-) ** Expl Sat Met-Satellite EXPL SAT. (E-S) MET-SAT. MET. AIDS (Radiosonde) METEOROLOGICAL AIDS (SONDE) (-to-space) (space-to-space) (deep space) (-to-space) (deep space) (-to-space) EXPLORATION - exploration - SATTELLITE sattellite EXPLORATION - Amateur (space-to-) (space-to-) LAND LAND LAND LAND LAND LAND LAND LAND LAND (space-to-) - (space-to-) - (space-to-) MOBIL-E - (space-to-) (space-to-) EXPLORATION exploration (-to-space) (space-to-) (space-to-) - ** (-to-space) ** Space Research - (-to-space) - (space-to-)(space-to-space) - (-to-space) LAND (medical telemetry and medical telecommand) (-to-space) - (-to-space) - - (-to-space) - NAVIGATION- - (-to-space) - - (-to-space) - (-to-space) - (-to-space) - (-to-space) (TELEVISION) LAND LAND LAND LAND LAND METEOROLOGICAL Amateur Amateur-satellite Amateur (space-to-) - Amateur (-to-space) (-to-space) - (-to-space) - (-to-space) - (-to-space)(space-to-) - (-to-space)(space-to-) - (-to-space) (deep space)(-to-space) (-to-space) - (space-to-) - (space-to-) Fixed ** ** - NAVIGATION - (space-to- ) LAND LAND LAND -satellite (space-to-) - (space-to-) -satellite (space-to-) METEOROLOGICAL - (space-to-) (space-to-) -satellite (space-to-) - (space-to-) METEOROLOGICAL- (space-to-) - (-to-space) - (-to-space) Fixed satellite (-to-space) (no airborne) (-to-space) satellite (space-to-) (-to-space) - (-to-space) (space-to-) (no airborne) (space-to-) -satellite (-to-space) (no airborne) - (-to-space) (space-to-) (deep space)(space-to-) (deep space)(space-to-) (space-to-) (space-to-)(space-to-space) (space-to-) (space-to-space) Meteorological Aids ** Fixed-satellite (-to-space) ** LAND (medical telemetry and medical telecommand) EXPLORATION - Amateur Amateur Amateur-satellite LAND LAND (medical telemetry and medical telecommand (telemetry and telecommand) (telemetry) (telemetry and LAND (telemetry & telecommand) telecommand) (telemetry and LAND Fixed-satellite telecommand) (telemetry & telecommand) (space-to-) ** (aeronautical telemetry) (space-to-) - (space-to-) (space-to-) (-to-space) Aeronatuical Radionavigation (space-to-)(space-to-space) (-to-space) (-to-space) (-to-space) DETERMINATION- (-to-space) DETERMINATION- (-to-space) DETERMINATION- (-to-space) -satellite (space-to-) - (-to-space) satellite (-to-space) research (-to-space) -satellite (space-to-) - (-to-space) (-to-space) METEOROLOGICAL AIDS (radiosonde) ** METEOROLOGICAL METEOROLOGICAL AIDS (space-to-) (radiosonde) Fixed METEOROLOGICAL (space-to-) OPERATION (-to-space) -satellite - Fixed (-to-space) (-to-space) Fixed Fixed EXPLORATION - - (-to-space) Radio astronomy ** Amateur Amateur - satellite (deep space)(-to-space) - (space-to-) - (space-to-) OPERATION (-to-space) (-to-space) (-to-space) OPERATION (-to-space) (space-to-space) (-to-space) - (space-to-) - (space-to-) - EXPLORATION - (space-to-) - (space-to-) - (space-to-) (space-to-) (space-to-) - (space-to-) - (space-to-) (space-to-) (space-to-) ** (deep space) Amateur Amateur ** Fixed Fixed EXPLORATION - ** - NAVIGATION- - (space-to-) Fixed LOC ATION Amateur EXPLORATION (-to-space) (space-to-) Amateur DETERMINATION- (space-to-) DETERMINATION- (space-to-) ** (space-to-) ** (-to-space) - (-to-space) - (-to-space) (space-to-) (space-to-) (-to-space) - - NAVIGATION METEOROLOGICAL Inter-satellite (-to-space) - (-to-space) - (-to-space) GHz Amateur-satellite Amateur Radioastronomy - 3 GHz (-to-space) NAVIGATION - (-to-space) NOT ALLOCATED 300 GHz Figure 10: US Department of Commerce shows the density of today s spectrum Source: The dictionary definition of coexist includes two ideas: to exist together at the same time and to live in peace with each other especially as a matter of policy. Both are fitting and relevant with 5G. Achieving the expected level of performance for any given communication system will depend on a peaceful coexistence. COEXISTENCE Top Considerations for 5G New Radio Device Designers 21

22 Two Key Coexistence Scenarios: 1) 5G coexistence with 4G and unlicensed spectrum Relatively new to 4G are LTE Unlicensed (LTE-U), licensed-assisted access (LAA), and MulteFire, all of which allow LTE operation in unlicensed spectrum. LAA uses the 4G network as an anchor and implements listen-before-talk to ensure no other operation is taking place in the unlicensed spectrum. LAA requires careful coexistence design and test with many different permutations due to the many different protocols being used in the same frequency bands. In addition to existing 4G operating bands, new 5G mid-band frequencies ( GHz, GHz, GHz) need to operate without causing interference with adjacent IEEE ac and ax Wi-Fi networks at 2.4 GHz and 5 GHz. Without proper filtering for each band, emissions from intermodulation can cause spurs that interfere with these and other adjacent bands: Frequency Band MHz MHz MHz , MHz GHz United States Spectrum Sharing Advanced Wireless Services 3 (AWS- 3) uses spectrum sharing amongst commercial networks and select government systems. Advanced Wireless Services 4 (AWS- 4) includes previous mobile satellite services. CBRS, or citizens broadband radio service, is a small-cell band with spectrum sharing and unlicensed use. 2) 5G coexistence with satellite and radar systems 5G not only needs to coexist with the existing commercial wireless infrastructure, but also with non-military radar and satellite signals, and with military usage in agencies such as the US Department of Defense. There is a proposal to use the unlicensed ISM (Industrial, Scientific and Medical) bands as a secondary channel, which creates shared spectrum scenarios that need to be tested. New 5G mmwave operating bands in frequency range 2 (FR2) also overlap with Fixed- Satellite Services (FSS) earth station uplinks at GHz and FSS downlinks at GHz. The Challenges The performance of a device transmitter at the edge of the band, and outside the band, can cause interference with other wireless communications. Emissions from harmonics, inter-modulation spurs, and spectral regrowth need to be evaluated so you can understand how the 5G NR signal will interact with other radio signals in the device or in other frequency bands. When it comes to shared spectrum, your device design needs to be able to sense its environment and modify behavior based on policy for the given location. While policy is still being defined, the most likely scenario is for commercial operators to only use the band when it is not in use by incumbents. This introduces the need for complex algorithms that can monitor and detect coexistence traffic and allocate or reallocate spectrum dynamically according to rules and policy without impacting QoS. This will require special tests not previously done on cellular devices. COEXISTENCE Top Considerations for 5G New Radio Device Designers 22

23 Tips for Overcoming Coexistence Challenges: View the constellation diagram and EVM of the demodulated signal as an indicator of good or poor coexistence. EVM per subcarrier can show effects of interference. Make wideband spectrum measurements such as Adjacent Channel Leakage Ratio (ACLR) and Spectrum Emissions Mask (SEM) to gain insight into the signal s interference possibilities. Integrate real-world behavior with a network emulator to validate spectrum sharing scenarios and identify excessive time allocating and reallocating spectrum. LEARN MORE Figure 11: Wideband signal generators and signal analyzers with demodulation software are used to create 5G/4G LTE coexistence scenarios for device validation White Paper: First Steps in 5G: Overcoming New Radio Device Challenges Series White Paper: Exploring 5G Coexistence Scenarios COEXISTENCE Top Considerations for 5G New Radio Device Designers 23

24 5G New Radio is Coming Faster Than You May Think New spectrum and technologies introduced with 5G NR will require you to think differently about how you design and test devices. These new technologies bring new test challenges in processing and validating wider bandwidths, testing and validating MIMO and beam steering performance, over-the air (OTA) testing methodologies, and 5G NR coexistence with other wireless communications systems. Keysight s portfolio of 5G NR solutions offer the tools to address these challenges with solutions to emulate, measure, and validate 5G RF and protocol signals so you develop more efficiently and accelerate your 5G NR device designs. COEXISTENCE Top Considerations for 5G New Radio Device Designers 24

25 Information is subject to change without notice EN Keysight Technologies, 2018 Published in USA, July 31, 2018 keysight.com Bluetooth and the Bluetooth logos are registered trademarks owned by Bluetooth SIG, Inc., and any use of such marks by Keysight Technologies is under license.