An Overview of Lo Ra Modulation Tallal Elshabrawy
An Overview of Lo. Ra Modulation Tallal Elshabrawy Faculty of Information Engineering & Technology (IET) The German University in Cairo (GUC)
Traditional Scope of Telecommunications
The New Era of Telecommunications
Lo. Ra Security Generic Telecommunication Framework for Io. T Applications
Data Collection Plane Technologies Battery Lifetime Years RFID LPWAN filling a Gap Months BLE IEEE 802. 15. 4 IEEE 802. 11 Days Few Meters Tens-Hundreds of Meters Kiliometers Communication Range
Io. T: Innovations of Telecommunications LPWAN Trends “NB-Io. T and Lo. Ra are forecasted to be the dominant technologies over the forecasted period in network and private network deployments respectively. ” public
Low Power Wide Area Networks Fundamentals Star/Star-of. Stars Simple Devices Centralized Control + Minimal Signaling Energy Efficient Communication + Push any Complexity away from Devices Reachability Low Data Rate + Low Receiver Sensitivity Reliability Simple Error Correction Techniques + Optional Retransmissions
The Growth of Lo. Ra Source: Lo. Ra Alliance™: https: //lora-alliance. org/
Lo. Ra Fundamentals: Patented Lo. Ra Modulation SF Rate* 7 5. 47 Kb/s 8 3. 12 Kb/s 9 1. 76 Kb/s 10 0. 98 Kb/s 11 0. 54 Kb/s 12 0. 29 Kb/s Ø Chirp Modulation Spread Spectrum Ø Multiple Parallel Networks based on Different SF Ø Control Data Rates/Coverage Ranges based on applied SF Ø A Lo. Ra Receiver can hear up to the Scale of 10000 times better than a Cellular Receiver SF 12 SF 11 SF 10 SF 9 SF 8 SF 7 -124 d. Bm -127 d. Bm -130 d. Bm -133 d. Bm -135 d. Bm -137 d. Bm
Lo. Ra Fundamentals: Lo. Ra. WAN Specification
Establish a Lo. Ra Network at Minimal Cost Lo. Ra Modules Lo. Ra Gateway The Things Network An Economic Path to Establish a LIVE Lo. Ra-Based Application
time (sec. ) amplitute frequency (Hz) Patented Chirp Spread Spectrum Lo. Ra Modulation time (sec. )
Dicrete Lo. Ra Chirp Signals
Lo. Ra Modulation Example frequency (Hz) DSP Realization time (sec. )
Lo. Ra De. Modulation Example Lo. Ra Demoulation = Dechirping + FFT
Lo. Ra Modulation/De. Modulation Summary Dechirping FFT SNR = -7 d. B In AWGN Rayleigh Rician
Lo. Ra Physical Layer Packet Ø Draguino Shield Ø Hope RFM 96 (SX 1276 Lo. Ra®) Ø “Hello World!“ Message d frequency (Hz) Ø Tx Frequency 868. 13 MHz time (sec. )
Preamble Detection Ø Correlate Symbol-by-Symbol Rx Signal with Basis Chirp Ø Consecutive Locations of Peak FFT Index indicates a Preamble Ø How Many Consecutive Symbols? Ø Some literature suggest four consective symbols Ø Do they have to be four and consecutive? Rx Power = -93. 84 d. Bm Rx Power = -124. 13 d. Bm
Patented Lo. Ra Generation v Accurate generation of the Lo. Ra chirps. v Digitally-synthesized Lo. Ra chirps. Lookup Table Symbol s Lack of Comprehensive mathematical representation Lo. Ra Chirp S 0 1 … 19
Cyclic-Time Shift Lo. Ra Formulation Lo. Ra Chirp Signals: v 20
Phase Continuous Lo. Ra Formulation Lo. Ra Chirp Signals: v 21
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