743 lines
22 KiB
TeX
743 lines
22 KiB
TeX
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\title[LoRa]{A Brief Introduction to \includegraphics[trim=0 4cm 0 0, scale=0.15]{images/lora.jpg}}
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\author{Simon Pirkelmann}
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\institute{\includegraphics[scale=0.5]{images/iR.pdf}}
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\date{December 2nd, 2019}
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\AfterPreamble{\hypersetup{
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urlcolor=blue,
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}}
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\begin{document}
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\begin{frame}
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\titlepage
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\end{frame}
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% Uncomment these lines for an automatically generated outline.
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\begin{frame}{Outline}
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\tableofcontents
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\end{frame}
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\section{LoRa}
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\subsection{Motivation}
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\begin{frame}{Motivation}
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\begin{itemize}
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\item Example: monitor well-being of honey bees\\[0.5cm]
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\includegraphics[scale=0.10]{images/honeybee.png}
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\hspace{0.5cm}
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\includegraphics[scale=0.055]{images/weight.png}
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\includegraphics[scale=0.045]{images/temperature.jpg}
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\includegraphics[scale=0.60]{images/humidity.jpg}\\[0.3cm]
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\hspace{6cm}
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\includegraphics[scale=0.04]{images/distance.jpg} \hspace{0.5cm}
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\includegraphics[scale=0.15]{images/no-electricity.png} \\
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\pause
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\begin{minipage}{0.40\textwidth}
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\vspace{-2cm}
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\item Requirements:
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\begin{itemize}
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\setlength{\itemsep}{0pt}
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\item Low data rate (a few bytes per day)
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\item Low power consumption
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\item Low cost
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\item Long range
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\end{itemize}
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\end{minipage}
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\pause
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\begin{minipage}{0.45\textwidth}
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\hspace{0.2cm}
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Options:
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\begin{itemize}
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\setlength{\itemsep}{0pt}
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\item Data line (e.g. ethernet)
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\item Wifi, Bluetooth
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\item Cellular
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\end{itemize}
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\end{minipage}
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\vspace{0.1cm}
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\pause
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\item Solution: LPWAN (\textbf{L}ow-\textbf{P}ower \textbf{W}ide-\textbf{A}rea \textbf{N}etwork)
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\begin{itemize}
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\item \textbf{LoRa}, \textbf{LoRaWAN}, \textbf{TheThingsNetwork}
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\item SigFox, NB-IoT, Weightless, ...
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\end{itemize}
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\end{itemize}
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\end{frame}
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\subsection{LoRa facts}
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\begin{frame}{LoRa Facts}
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\begin{reference}{0mm}{70mm}
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https://www.thethingsnetwork.org/docs/lorawan/
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\end{reference}
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\begin{itemize}
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\item Developed by \textbf{Semtech} (originally by Cycleo)\\
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\hspace{0.3 cm}\textbf{Note:} parts of the PHY layer are \textbf{proprietary}!
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\item Frequency: \textbf{868 MHz} \textbf{SRD} band (in the EU)
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\item \textbf{25 mW} transmission power
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\item Bandwidth: \textbf{125} to \textbf{500 kHz}
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\item Data rate between \textbf{250 Bit/sec} and 21 \textbf{kBit/sec} \\
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\hspace{0.3 cm}\textbf{BUT}: not made for a lot of data
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\item Low cost: \textbf{$\sim $10 EUR} CAPEX (for nodes), almost no OPEX
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\item Low power: devices can last \textbf{years on battery}
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\item Long distance: up to \textbf{10 km} range
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\end{itemize}
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\only<2>{
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\begin{textblock*}{100mm}(-5mm,-65mm)
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\textblockcolour{white}
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\begin{exampleblock}{LoRa distance record}
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\includegraphics[scale=0.3]{images/distance_record.png}
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\end{exampleblock}
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\end{textblock*}
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}
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\end{frame}
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\begin{frame}{LoRa facts}
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\begin{reference}{0mm}{75mm}
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https://www.thethingsnetwork.org/docs/lorawan/
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\end{reference}
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LoRa is \textbf{NOT} for:
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\begin{itemize}
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\item Realtime data - only small packets, every couple of minutes
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\item Phone calls - you can do that with GPRS/3G/LTE
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\item Controlling lights in your house - check out ZigBee or BlueTooth
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\item Sending photos, watching Netflix - check out WiFi
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\end{itemize}
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Important: \includegraphics[trim=0cm 4cm 0 0cm, scale=0.11]{images/lora.jpg} $\leftrightarrow$ \includegraphics[trim=0cm 4cm 0 0cm,scale=0.15]{images/lorawan.jpg} $\leftrightarrow$ \includegraphics[trim=0cm 4cm 0 0cm,scale=0.06]{images/ttn.png}\\[0.3cm]
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\begin{itemize}
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\item \textbf{LoRa}: PHY layer $\Rightarrow$ modulation technique
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\item \textbf{LoRaWAN}: Network protocol
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\item \textbf{TheThingsNetwork (TTN)}: Network server, handles routing of data to the \textit{cloud}
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\end{itemize}
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\end{frame}
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\subsection{PHY layer: modulation and demodulation}
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\begin{frame}{Digital modulation}
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\begin{itemize}
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\item \textbf{A}mplitude \textbf{S}hift \textbf{K}eying (ASK)
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\end{itemize}
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\includegraphics[scale=0.35]{images/unmodulated.png}
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\includegraphics<1>[scale=0.35]{images/amplitude_modulation.png}
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\includegraphics<2>[scale=0.35]{images/amplitude_modulation_2.png}
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\end{frame}
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\begin{frame}{Digital modulation}
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\begin{reference}{0mm}{75mm}
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https://en.wikipedia.org/wiki/Chirp\_spread\_spectrum
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\end{reference}
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\begin{itemize}
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\item \textbf{F}requency \textbf{S}hift \textbf{K}eying (FSK)
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\end{itemize}
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\includegraphics[scale=0.35]{images/unmodulated.png}
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\includegraphics<1>[scale=0.35]{images/frequency_modulation.png}
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\includegraphics<2>[scale=0.35]{images/frequency_modulation_2.png}
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\end{frame}
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\begin{frame}{Digital modulation}
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\begin{itemize}
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\item Used by LoRa: \textbf{C}hirp \textbf{S}pread \textbf{S}pectrum (CSS) modulation
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\begin{center}
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\includegraphics[scale=0.3]{images/chirp.png}
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\includegraphics[scale=0.3]{images/chirp_spectrogram.png}
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\end{center}
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\begin{itemize}
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\item Chirp = frequency change over time\\
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\end{itemize}
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\end{itemize}
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\end{frame}
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\begin{frame}{LoRa modulation}
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\begin{itemize}
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\item LoRa uses \textbf{Up-Chirps} (frequency increases) and \textbf{Down-Chirps} (frequency decreases)
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\end{itemize}
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\includegraphics[scale=0.3]{images/lora_upchirp.png}
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\includegraphics[scale=0.3]{images/lora_downchirp.png}
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%\item Messages always start with 8 Up-Chirps
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\end{frame}
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\begin{frame}{Example LoRa packet}
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\begin{reference}{0mm}{70mm}
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Thanks Valentin and Stefan (DM4SG) for providing this data
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\end{reference}
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\begin{center}
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\includegraphics<1>[scale=0.2]{images/lora_signal.png}
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\includegraphics<2>[scale=0.2]{images/lora_signal_2.png}
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\includegraphics<3>[scale=0.2]{images/lora_signal_3.png}
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\end{center}
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\end{frame}
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\begin{frame}{Chirps and Symbols}
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\begin{overlayarea}{\textwidth}{\textheight}
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\begin{center}
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\includegraphics<1>[scale=0.38]{images/lora_symbols_0.png}
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\includegraphics<2>[scale=0.38]{images/lora_symbols_1.png}
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\includegraphics<3>[scale=0.38]{images/lora_symbols_2.png}
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\includegraphics<4>[scale=0.38]{images/lora_symbols_3.png}
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\includegraphics<5>[scale=0.38]{images/lora_symbols_4.png}
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\includegraphics<6>[scale=0.38]{images/lora_symbols_5.png}
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\includegraphics<7>[scale=0.35]{images/lora_demodulation_0.png}
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\includegraphics<7>[scale=0.35]{images/lora_demodulation_1.png}
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\includegraphics<8>[scale=0.38]{images/lora_demodulation_2.png}
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\end{center}
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\only<2->{
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Time of frequency jump determines which data is encoded\\
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}
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\begin{center}
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\only<3>{Example: \texttt{data = }\texttt{00000}}
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\only<4>{Example: \texttt{data = }\texttt{00010}}
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\only<5>{Example: \texttt{data = }\texttt{00011}}
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\only<6>{Example: \texttt{data = }\texttt{10110}}
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\end{center}
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\only<7->{
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\vspace{-0.75cm}
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\textbf{Demodulation:}
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\begin{itemize}
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\item De-chirp signal by multiplying (mixing) with conjugate chirp
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\item Fourier Transform
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\item Alignment using detect sequence at start of transmission
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\end{itemize}
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}
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\end{overlayarea}
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\end{frame}
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\begin{frame}{Spreading factor}
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\begin{itemize}
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\item Number of bits per symbol is determined by \textbf{spreading factor} (SF)
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\begin{center}
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\includegraphics<1>[scale=0.5]{images/lora_spreading_factors.png}
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\end{center}
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\item Possible values: SF7 - SF12\\
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\hspace{0.5cm} SF7: 7 bits per symbol \\
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\hspace{0.5cm} SF12: 12 bits per symbol
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\item Spreading factor influences max. range
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\end{itemize}
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\end{frame}
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\begin{frame}{Demodulation}
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\begin{itemize}
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\item De-chirp signal by multiplying (mixing) with conjugate chirp
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\item Fourier Transform
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\end{itemize}
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\end{frame}
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\begin{frame}{Forward error coding}
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\begin{itemize}
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\item For each symbol several \textbf{parity bits} are added (= redundant information) \\
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Reason: allows to detect and fix errors that occur during transmission (due to interference, etc.)
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\item \textbf{Coding rate} determines number of parity bits:\\
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\hspace{0.25cm} CR 4/5 : of 5 bits transmitted, 4 bits are actual data\\
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\hspace{1.5cm}$\vdots$\\
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\hspace{0.25cm} CR 4/8 : of 8 bits transmitted, 4 bits are actual data
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\item Additionally: \textbf{C}yclical \textbf{R}edundancy \textbf{C}heck (CRC)
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\end{itemize}
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\end{frame}
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\subsection{Packet format}
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\begin{frame}{LoRa package format}
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\begin{reference}{0mm}{70mm}
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Source: SX1276/77/78/79 datasheet
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\end{reference}
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\includegraphics[scale=.3]{images/lora_packet_structure.png}
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\begin{itemize}
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\item Header: contains information about
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\begin{itemize}
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\item payload length
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\item coding rate
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\item CRC present?
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\end{itemize}
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\item Implicit header mode: no header sent
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\end{itemize}
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\end{frame}
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\subsection{Data rate and air time}
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\begin{frame}{Data rate and air time}
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\begin{itemize}
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\item Data rate depends on bandwidth (BW), spreading factor (SF) and coding rate (CR)\\[0.3cm]
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\begin{minipage}{0.4\textwidth}
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\textbf{Symbol duration}:
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\begin{equation*}
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T_{sym} = \frac{2^{SF}}{BW}
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\end{equation*}
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\end{minipage}
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\begin{minipage}{0.5\textwidth}
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\textbf{Symbol rate}:
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\begin{equation*}
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R_{sym} = \frac{1}{T_{sym}}
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\end{equation*}
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\end{minipage}
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\item \textbf{Data rate}:
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\begin{equation*}
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R_{data} = \underbrace{SF}_{\# \text{bits per symbol}} \cdot \underbrace{R_{symb}}_{\text{symbol rate}} \cdot \underbrace{\frac{4}{4 + CR}}_{\text{coding rate}}
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\end{equation*}
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\item Example data rates:\\
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\begin{tabular}{lll|lr}
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SF7 &BW250 &CR4/5 & $\approx 10.9$ &$\tfrac{kbit}{s}$ \\ \hline
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SF7 &BW125 &CR4/5 & $\approx 5.5$ &$\tfrac{kbit}{s}$ \\ \hline
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SF12 &BW125 &CR4/5 & $\approx 0.29$ & $\tfrac{kbit}{s}$
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\end{tabular}
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%\item Sync word: \url{https://forum.chirpstack.io/t/relation-between-sync-word-private-network-and-end-nodes/191/17}
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\end{itemize}
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\end{frame}
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\begin{frame}{Time-On-Air}
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\begin{reference}{0mm}{65mm}
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According to \textit{Allgemeinzuteilung von Frequenzen zur Nutzung durch Funkanwendungen mit geringer Reichweite für nicht näher spezifizierte Anwendungen; Non-specific
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Short Range Devices (SRD)}, Bundesnetzagentur, 2018
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\end{reference}
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\begin{itemize}
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\item Comply with \textbf{duty cycles} of the SRD band:
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\begin{tabular}{l|r|r}
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Frequency & Duty Cycle & ERP \\
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\hline
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868,0 - 868,6 MHz & 1 \% & 25 mW
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\end{tabular}
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\item This amounts to $\approx 30$ seconds of transmission time per hour (maximum!). Try to keep it way below.
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\item Airtime calculator: \url{https://www.loratools.nl/\#/airtime}
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\item Example: \texttt{20 bytes} payload \\
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$\rightarrow$ max. 25 messages per hour on SF12 \\
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$\rightarrow$ max. 600 messages per hour on SF7 \\
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|
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\end{itemize}
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\end{frame}
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\section{Playground Part I}
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\begin{frame}[fragile]{Playground Part I}
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\begin{small}
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\begin{itemize}
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\item Module used: \textbf{Wemos® TTGO LORA32 868Mhz ESP32}
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\begin{minipage}{0.6\textwidth}
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\begin{small}
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\begin{itemize}
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\item ESP32
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\item LoRa Chip SX1276
|
|
\item OLED display
|
|
\item Antenna (needs to be connected!)
|
|
\end{itemize}
|
|
\end{small}
|
|
\end{minipage}%
|
|
\begin{minipage}{0.4\textwidth}
|
|
\includegraphics[scale=0.075]{images/ttgo_module.JPG}
|
|
\end{minipage}
|
|
\item Programmable in MicroPython thanks to \texttt{uPyLora} library by lemariva (\url{https://github.com/lemariva/uPyLora})
|
|
|
|
\begin{spacing}{0.84}
|
|
\begin{python}
|
|
from lora_transceiver import LoRaTransceiver
|
|
from uPySensors.ssd1306_i2c import Display
|
|
|
|
disp = Display()
|
|
|
|
# create transceiver
|
|
lora = LoRaTransceiver(display=disp)
|
|
|
|
# send a string
|
|
lora.send_string("Hello World!")
|
|
|
|
# send some raw binary data
|
|
lora.send([0x01, 0x02, 0x03])
|
|
\end{python}
|
|
\end{spacing}
|
|
\vspace{-0.1cm}
|
|
\item Alternative: HopeRF \textbf{RFM95W} chip
|
|
\item For "documentation" see: \url{https://imaginaerraum.de/git/Telos4/LoRa-Workshop}
|
|
\end{itemize}
|
|
\end{small}
|
|
\end{frame}
|
|
|
|
\begin{frame}[fragile]{Playground Part I}
|
|
\begin{itemize}
|
|
\item Receiving data:
|
|
\begin{spacing}{0.84}
|
|
\begin{python}
|
|
from lora_transceiver import LoRaTransceiver
|
|
from uPySensors.ssd1306_i2c import Display
|
|
|
|
disp = Display()
|
|
|
|
# create transceiver
|
|
lora = LoRaTransceiver(display=disp)
|
|
|
|
# start receiving data (and output on the screen)
|
|
lora.recv()
|
|
\end{python}
|
|
\end{spacing}
|
|
\item Change LoRa parameters
|
|
\begin{spacing}{0.85}
|
|
\begin{python}
|
|
# change the spreading factor
|
|
lora.setSpreadingFactor(10)
|
|
|
|
# change the frequency
|
|
lora.setFrequency(868.1e6)
|
|
|
|
# change signal bandwidth
|
|
lora.setSignalBandwidth(250e3)
|
|
|
|
# change sync word
|
|
lora.setSyncWord(0x34)
|
|
\end{python}
|
|
\end{spacing}
|
|
\item Task: \textit{Turn off your neighbors LED!}
|
|
\end{itemize}
|
|
\end{frame}
|
|
|
|
\section{LoRaWAN}
|
|
\subsection{Network topology}
|
|
\begin{frame}{LoRaWAN}
|
|
\begin{reference}{2mm}{80mm}
|
|
https://www.thethingsnetwork.org/docs/lorawan/
|
|
\end{reference}
|
|
\begin{itemize}
|
|
\item LoRaWAN is for getting your sensor data online
|
|
\item Media access control (MAC) protocol
|
|
\item Network topology:\\
|
|
\begin{center}
|
|
\includegraphics[scale=0.085]{images/lorawan_topology.png}
|
|
\end{center}
|
|
\item \textbf{Gateways} forward data from nodes to the \textit{cloud}
|
|
\item Transmission is secured by AES-128 encryption
|
|
\end{itemize}
|
|
\end{frame}
|
|
|
|
\subsection{TheThingsNetwork}
|
|
\begin{frame}{Device registration}
|
|
\begin{itemize}
|
|
\item \textbf{TheThingsNetwork} aims to build a global LoRaWAN network
|
|
\item Devices need to be registered and assigned to an application before they can communicate with the network
|
|
\begin{enumerate}
|
|
\item Create an account on \url{https://www.thethingsnetwork.org/}
|
|
\item Log in and open the \textit{Console}
|
|
\item
|
|
\begin{minipage}{0.35\textwidth}
|
|
\vspace{-1.85cm}Create an application
|
|
\end{minipage}%
|
|
\begin{minipage}{0.6\textwidth}
|
|
\vspace{-0.2cm}
|
|
\includegraphics[scale=0.08]{images/lorawan_application.png}
|
|
\end{minipage}
|
|
\item Create a device and register it. Go to \textit{Settings} and change activation method to Activation by Personalisation (ABP)\\
|
|
\includegraphics[scale=0.08]{images/lorawan_abp.png}
|
|
\end{enumerate}
|
|
\end{itemize}
|
|
\end{frame}
|
|
|
|
\begin{frame}{Keys}
|
|
\begin{reference}{2mm}{80mm}
|
|
https://nootropicdesign.com/projectlab/2018/10/28/lorawan-end-devices/
|
|
\end{reference}
|
|
\begin{itemize}
|
|
\item Three important keys (when using ABP):\\
|
|
\begin{scriptsize}
|
|
\begin{center}
|
|
\hspace*{-8pt}\makebox[\linewidth][c]{%
|
|
\begin{tabular}{l|l}
|
|
Device Address (\textbf{DevAddr}) & identification of the device in TTN \\
|
|
\hline
|
|
Network Session Key (\textbf{NwkSKey}) & secure communication between device and TTN \\
|
|
\hline
|
|
Application Session Key (\textbf{AppSKey}) & secure communication between device and application
|
|
\end{tabular}
|
|
}
|
|
\end{center}
|
|
\end{scriptsize}
|
|
\begin{itemize}
|
|
\item DevAddr tells TTN where to route the data
|
|
\item NwkSKey used for message validity check (MIC)\\ (prevents tampering with messages)
|
|
\item AppSKey are used for payload encryption/decryption\\ (prevents reading the data)
|
|
\item Need to be \textbf{hardcoded} into the device
|
|
\end{itemize}
|
|
\item Alternatively: use Over-the-Air Activation (OTAA) (more secure)
|
|
\item Frame counters: Each message is equipped with a counter that prevents re-transmit attacks
|
|
\end{itemize}
|
|
\begin{reference}{2mm}{70mm}
|
|
https://www.thethingsnetwork.org/forum/t/limitations-data-rate-packet-size-30-seconds-uplink-and-10-messages-downlink-per-day-fair-access-policy-guidelines/1300
|
|
\end{reference}
|
|
\end{frame}
|
|
|
|
\begin{frame}{LoRaWAN payload format}
|
|
\begin{reference}{2mm}{70mm}
|
|
http://www.techplayon.com/lora-long-range-network-architecture-protocol-architecture-and-frame-formats/
|
|
\end{reference}
|
|
\begin{center}
|
|
\includegraphics[scale=0.35]{images/lorawan_payload_format.png}
|
|
\end{center}
|
|
Useful link:
|
|
\begin{itemize}
|
|
\item LoRaWAN packet decoder {\small \url{https://lorawan-packet-decoder-0ta6puiniaut.runkit.sh/}}
|
|
\end{itemize}
|
|
\end{frame}
|
|
|
|
\subsection{Applications}
|
|
\begin{frame}{Use cases}
|
|
\begin{reference}{0mm}{80mm}
|
|
\url{https://www.semtech.com/lora/resources/lora-white-papers}
|
|
\end{reference}
|
|
\begin{minipage}{0.5\textwidth}
|
|
\begin{flushleft}
|
|
\textbf{Smart farming}
|
|
\end{flushleft}
|
|
\includegraphics[scale=0.09]{images/smart_farming.png}
|
|
\end{minipage}%
|
|
\begin{minipage}{0.5\textwidth}
|
|
\begin{flushright}
|
|
\textbf{Smart parking}
|
|
\end{flushright}
|
|
\includegraphics[scale=0.09]{images/smart_parking.png}
|
|
\end{minipage}
|
|
\begin{minipage}{0.5\textwidth}
|
|
\begin{flushleft}
|
|
\textbf{Smart home}
|
|
\end{flushleft}
|
|
\includegraphics[scale=0.09]{images/smart_home.png}
|
|
\end{minipage}%
|
|
\begin{minipage}{0.5\textwidth}
|
|
\begin{flushright}
|
|
\textbf{Smart waste management}
|
|
\end{flushright}
|
|
\includegraphics[scale=0.09]{images/smart_waste.png}
|
|
\end{minipage}%
|
|
|
|
\end{frame}
|
|
|
|
\section{Playground Part II}
|
|
\begin{frame}[fragile]{Playground Part II}
|
|
Example code for sending data to \textbf{TheThingsNetwork}:
|
|
\begin{spacing}{0.85}
|
|
\begin{python}
|
|
from lora_transceiver import LoRaTransceiver
|
|
from uPySensors.ssd1306_i2c import Display
|
|
import uLoRaWAN
|
|
from uLoRaWAN.MHDR import MHDR
|
|
|
|
disp = Display()
|
|
|
|
# create transceiver for LoRaWAN frequency (channel 0 = 868.1 Mhz)
|
|
lora = LoRaTransceiver(frequency=868.1E6, syncword=0x34, display=disp)
|
|
|
|
# set address and keys for LoRaWAN (with ABP)
|
|
devAddr = [0x26, 0x01, 0x16, 0x5C] # ir_test_device_01
|
|
nwkSKey = [0x9D, 0x95, 0x0F, 0xAB, 0xCB, 0x63, 0xD3, 0x04, 0xBC, 0x09,
|
|
0xC4, 0x9E, 0xC5, 0xDF, 0x3C, 0x37]
|
|
appSKey = [0xC9, 0x6C, 0x00, 0xD1, 0xB0, 0x1C, 0x2E, 0x42, 0x11, 0xBA,
|
|
0x32, 0x6F, 0x2F, 0xC2, 0x75, 0x6A]
|
|
|
|
# lorawan object for conversion of data in LoRaWAN message format
|
|
lorawan = uLoRaWAN.new(nwkSKey, appSKey)
|
|
|
|
message = list(map(ord, 'Hello World!')) # convert to bytes
|
|
lorawan.create(MHDR.UNCONF_DATA_UP, { 'devaddr': devAddr, 'fcnt': 0,
|
|
'data': message })
|
|
payload = lorawan.to_raw()
|
|
|
|
lora.send(payload)
|
|
\end{python}
|
|
\end{spacing}
|
|
(the code is based on the \texttt{uLoRaWAN} library by mallagant, see: {\small \url{https://github.com/mallagant/uLoRaWAN}})
|
|
\end{frame}
|
|
|
|
\begin{frame}[fragile]{Playground Part II}
|
|
For testing you can use the following device addresses and keys:
|
|
\begin{itemize}
|
|
\item
|
|
\textbf{nwkSKey}
|
|
\begin{python}
|
|
9D 95 0F AB CB 63 D3 04 BC 09 C4 9E C5 DF 3C 37
|
|
\end{python}
|
|
\item \textbf{appSKey}
|
|
\begin{python}
|
|
C9 6C 00 D1 B0 1C 2E 42 11 BA 32 6F 2F C2 75 6A
|
|
\end{python}
|
|
\item \textbf{devAddr} (choose one):
|
|
\begin{python}
|
|
1: 26 01 16 5C 10: 26 01 1A CE
|
|
2: 26 01 18 52 11: 26 01 12 F1
|
|
3: 26 01 1E 4F 12: 26 01 1B 18
|
|
4: 26 01 17 83 13: 26 01 19 40
|
|
5: 26 01 1B 5C 14: 26 01 19 96
|
|
6: 26 01 1E B5 15: 26 01 18 FF
|
|
7: 26 01 13 DA 16: 26 01 12 5B
|
|
8: 26 01 1E 8F 17: 26 01 13 63
|
|
9: 26 01 18 F1 18: 26 01 12 09
|
|
\end{python}
|
|
\item Watch incoming data (forwarded as HTTP POST request) at
|
|
\begin{center}
|
|
\url{https://t1p.de/ocp6}
|
|
\end{center}
|
|
and check the gateway log at (connected to @BayernWLAN wifi)
|
|
\begin{center}
|
|
\url{http://192.168.1.1:1337}
|
|
\end{center}
|
|
\end{itemize}
|
|
\end{frame}
|
|
|
|
\begin{frame}{References and more information}
|
|
\begin{footnotesize}
|
|
\textbf{References:}
|
|
\begin{itemize}
|
|
\item Decoding LoRa \url{https://revspace.nl/DecodingLora}
|
|
\item \textit{LoRa und The Things Network} - talk by Hubert Högl (FH Augsburg)
|
|
\item \href{https://electronics.stackexchange.com/questions/278192/understanding-the-relationship-between-lora-chips-chirps-symbols-and-bits}{Stackexchange thread about LoRa symbols}
|
|
\item \href{http://wireless.ictp.it/school_2017/Slides/LoRaDetails.pdf}{LoRa talk}
|
|
\item \href{https://www.youtube.com/playlist?list=PLmL13yqb6OxdeOi97EvI8QeO8o-PqeQ0g}{Mobilefish.com LoRa youtube tutorials}
|
|
\end{itemize}
|
|
|
|
\textbf{Further reading:}
|
|
\begin{itemize}
|
|
\item TTN Applications: APIs, Python SDK, Integrations {\scriptsize \url{https://www.thethingsnetwork.org/docs/applications/}}
|
|
\item Best practices to reduce payload size: {\scriptsize \url{https://www.thethingsnetwork.org/forum/t/best-practices-to-limit-application-payloads/1302}}
|
|
\item Forum about all things LoRa: \url{https://www.thethingsnetwork.org/forum/}
|
|
\begin{itemize}
|
|
\item Gateway guides
|
|
\item Radio module/antenna recommendations
|
|
\item ...
|
|
\end{itemize}
|
|
\item Cayenne Low Power Payload (LPP)
|
|
\end{itemize}
|
|
\end{footnotesize}
|
|
\pause
|
|
\begin{center}
|
|
\textbf{Thanks for your attention!}
|
|
\end{center}
|
|
\end{frame}
|
|
|
|
\end{document}
|