Spectrum management Anders P. Mynster, Wireless specialist, apm@delta.dk
What is the spectrum used for? Cell phones
What is the spectrum used for? GPS Location
What is the spectrum used for? Radar
What is the spectrum used for? TV, Internet, Satellites, Garage door, Thermometer WWW
What is the spectrum used for? Heating a chicken in our microwave
Wireless communication system Technologies Short range Long range Standards Regulatory approvals EU approvals US approvals System Interface Encoding Security System integration Application Data management Communication channel Antennas Site propagation Interference Link budget Datarate
Wireless Technologies Bluetooth DSRC 915 MHz Millenial Net Bluetooth ULP DSRC 5.7GHz Weightless RF4CE EnOcean WirelessHD(HR PHY) ZigBee, 2.4 GHz MiWi, 2.4 GHz WirelessHD(LR PHY) ZigBee, 915 MHz (USA) MiWi, 915 MHz (USA) WirelessHART ZigBee, 868 MHz (EU) MiWi, 868 MHz (EU) ISA-SP100.11a ZigBee PRO, 2.4 GHz WAP DECT 6.0 802.11 FHSS 6LowPAN/IPv6 Cat-iq Wi-Fi classic SimpliciTI GSM (2G) Wi-Fi 11a Sensinode GPRS/EDGE (2.5G) Wi-Fi 11b Wireless Desktop Protocol UMTS/CDMA (3G) Wi-Fi 11g Synapse wireless HSPA (3.5G) Wi-Fi 11n Scatterweb LTE Advanced (4G) Z-Wave(EU) KNX UWB-WiMedia Z-Wave(US) DECT NFC (passive +active) Z-Wave(Far East) WirelessUSB(cypress) NFC active only Ant RuBee WiMax(WiBro in Japan) Wavenis Cwave(pulse link) RLAN Wireless USB TransferJet Ensation Wireless M-bus MediaFLO TinyMesh UWB-WiMedia TETRA Proprietary 6LowPAN KNX-RF Analog
Multiple users Cell phones, WiFi, bluetooth, FM radio and TV all communicate simulataneously How? GPS = -160 dbm = 10-19 W FM transmitter = 1000 W = 10 3 W The difference is a factor of 10 22 There are approximately 10 22 stars in the universe 3 ways to share FDMA TDMA CDMA
Spectrum
Wavelength λ= c/f
Link budgets Pr P t = λ 4 π 2 GtG R r N Frequency[MHz] 868 Pt[dBm] 5 Gt[dBi] 2 Transmitter matching loss[db] 3 Casing loses[db] 2 EIRP 2 Effective Receiver sensitivity[dbm] -105,0 Gr[dBi] 2 Receiver matching loses[db] 3 Casing loses[db] 2 Fast fading margin[db] 7,5 Total input gain[db] -10,5 N 4,0 d 12,1
Antennas Size matters The gain of an antenna is related to the electrical size G = 54dBi Bluetooth Pt = 20dBm Pr = -80dBm Distance to the moon = 363104-405696 km R = λ 4π 2 G G P t r t = km P 249862 r
Fading and antenna diversity
MIMO Multiple input multiple output
Spectrum
Electromagnetic compatibility Radiated emission on all electronics is measured to protect the radio frequency bands Level [dbµv/m] 100 80 60 40 20 0 30M 50M 70M 100M 200M 300M 500M 700M 1G Frequency [Hz] MES RE 30-1000 bag MaxPk LIM RE, EN 55011 30m, QP Radiated Emission
1890s - First electromagnetic noise problems Telegraph lines with twists Graham Bell Law of Telegraph in the German Empire - 1892
RED and EMC directives
Licensed vs. unlicensed Buy a national license for a frequency band Danish has won 2x20 MHz (801-821 MHz and 842-862 MHz) in Denmark. Combined licensing price 627,804,000.- dkk = $100 million USD Buy a regional license Down to approximately 5,000 DKK = 900 USD per location Use an unlicensed band ( see ERC/REC 70-03 for additional bands) All free of charge 433 MHz 868 /915 MHz 2400 MHz 5700 MHz
Duty cycle and TDMA When multiple users share the same frequency band For many unlicensed bands there are limitations on how large a percentage of time transmission is allowed to share it with other users
Co-existence 433 MHz proprietary 2,4GHz WiFi Mounting device for windmill wings 3 wireless connections 433 MHz proprietary
Co-existence Wireless Camera WiFi
Internet of things
5G Source: IEEE communication society: Realizing 5G - ofcom
5G 5G PPP important vertical sectors: Factories of The Future Automotive Health Energy Media & Entertainment Requires different data rate, mobility, latency, density, reliability, positioning accuracy and coverage
Spectrum management Politics can be seen as a distribution of power and resources within a given community Spectrum management is about distributing the ressource of electromagnetic spectrum by: Identification of needs for spectrum coordination Initiating harmonisation of spectrum usage Establishment of policy priorities Setting the regulatory environment
WiFi or food?
Spectrum management Questions?