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--- exploring_lora [2018/09/27 10:33] – samer
+++ exploring_lora [2018/09/27 15:45] – [3.2. Running Basic Sketches] samer
@@ Line 8: / Line 8: @@
   * How LoRa is compatible with LPWAN requirements and constraints?
 </WRAP>
-===== -. Hardware Platform =====
+===== -. Setting the Lab =====
+==== -. Hardware Platform ====
 In order to design and implement experiments with LoRa, you will use the following devices:
@@ Line 21: / Line 24: @@
   * Give an estimated cost of your platform.
 </WRAP>
-===== -. Software Tools =====
+==== -. Software Tools ====
 Download the following software on your PC:
@@ Line 32: / Line 36: @@
 Note well the location of the library folder on your computer. In the following, you will be required to modify source files located in this folder.
 </WRAP>
-===== -. Installation =====
+==== -. Installation ====
 Start by plugging the Dragino shields on the Arduino devices and mounting the antennas as shown in Fig. 1.
@@ Line 46: / Line 51: @@
 </WRAP>
-===== -. Theoretical Analysis =====
+===== -. Theoretical Study =====
 In this section, you will perform a theoretical assessment of the performance of LoRa modulation. You will later compare this theoretical results to the experimental ones as in a typical scientific study.
@@ Line 58: / Line 63: @@
 </WRAP>
-===== -. Running Basic Sketches =====
+===== -. Configuring and Running the Lab =====
-Start by setting the central frequency of the LoRa modules. For this, open the ''RH_RF95.cpp'' file locate in the ''RadioHead'' folder and change the frequency to 868.10 (Group 1), 868.30 (Group 2), and 868.50 MHz (Group 3).
-<file cpp RH_RF95.cpp>
+==== -. Modifying the Radio Parameters ====
-setFrequency(868.X);
-</file>
-Download the {{ :example-lora-sketch.zip | basic sketches}} that implement a reliable LoRa communication between the two modules. Open the sketches with Arduino IDE, compile and upload on the two arduino modules, respectively. On the serial interfaces, you should obtain similar results as in Fig. 2 and Fig. 3. The client sends a short message and waits for an acknowledgement message from the server. Both modules output the RSSI (received power in dBm) for each received message.
+Start by setting the central frequency of your LoRa modules according to the following table:
-[{{ :client-iotlab1.png?direct&600 ||Figure 2. Client serial monitor}}]
+^  Group Number  ^   Frequency     ^
-[{{ :server-iotlab1.png?direct&600 ||Figure 3. Server serial monitor}}]
+|       1        |      866.7      |
+|       2        |      866.9      |
+|       3        |      867.1      |
+|       4        |      867.3      |
+|       5        |      867.5      |
+|       6        |      867.7      |
+|       7        |      867.9      |
+|       8        |      868.1      |
+|       9        |      868.3      |
+|       10       |      868.5      |
+|       11       |      868.7      |
+|       12       |      868.9      |
-===== -. Modifying the Radio Parameters =====
+For this, open the ''RH_RF95.cpp'' file located in the ''RadioHead'' folder and change the frequency using the following command:
+<file cpp RH_RF95.cpp>
+setFrequency(86X.Y);
+</file>
 The typical configuration for LoRa modules consists of 125 kHz sub-channels, a coding rate of 4/5, and a spreading factor equal to 7. You can modify the radio parameters by selecting one of the three available configurations:
@@ Line 82: / Line 99: @@
 setModemConfig(Bw125Cr45Sf128);
 </file>
+==== -. Running Basic Sketches ====
-In the remainder of this lab, you will conduct measurements to validate the obtained theoretical receiver sensitivity.
+Download the {{ :example-lora-sketch.zip | basic sketches}} that implement a simple LoRa communication between the two modules. Open the sketches with Arduino IDE, compile and upload on the two arduino modules, respectively. On the serial interfaces, you should obtain similar results as in Fig. 2 and Fig. 3. The client sends periodically a short message and towards the server. The server outputs the RSSI (received power in dBm) for each received message.
+[{{ :client-iotlab1.png?direct&600 ||Figure 2. Client serial monitor}}]
+[{{ :server-iotlab1.png?direct&600 ||Figure 3. Server serial monitor}}]
+In the remainder of this lab, you will conduct measurements to validate the obtained theoretical receiver sensitivity.
 ===== -. Performance Evaluation =====
 In the following, you will design and implement a set of scenarios that enable to evaluate the performance of the LoRa modulation. As you will deal with scientific assessment, you are required to use scientific tools to show the results. You have the choice between [[http://www.gnuplot.info | gnuplot]], [[https://matplotlib.org/index.html#|matplotlib]] with Python, and MATLAB. Take some time to become familiar with one of these software as you will be required to use them in different occasions of your academic programme.
@@ Line 98: / Line 120: @@
-==== -. Packet Error Rate ====
+==== -. Packet Delivery Ratio ====
 In this section, you will measure the Packet Error Rate (PER) under the three different radio configurations and for different transmission periods. For this, you can start by implementing a function on the client that measures the ratio of successfully delivered packets.