Differences

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--- exploring_lora [2018/09/29 14:03] – [4. Performance Evaluation] samer
+++ exploring_lora [2018/09/29 15:39] – [4.3. Coverage] samer
@@ Line 121: / Line 121: @@
 ==== -. Time on Air ====
-In this section, you will measure the Time on Air (ToA) as given by the time necessary to transmit a message on the radio interface. You will assess the impact of the spreading factor, bandwidth, coding rate, the message size on the ToA.
+In this section, you will measure the Time on Air (ToA) as given by the time necessary to transmit a message on the radio interface. You will assess the impact of the spreading factor, bandwidth, coding rate, and the message size on the ToA.
-For this, you can start by implementing a function on the client that measures the time necessary for sending a message. For example, you can use the [[https://www.arduino.cc/en/Reference/Micros| micros()]] function available in the arduino libraries. As we are in presence of variable experimental conditions, experiments should be repeated.
+For this, you will start by implementing a function on the client that measures the time necessary for sending a message. For example, you can use the [[https://www.arduino.cc/en/Reference/Micros| micros()]] function available in the arduino libraries. Now, you can modify one of the parameters (spreading factor, bandwidth, coding rate, message size) and record the impact on the ToA. Note well that you may need to repeat the expriment to obtain the statistical distributions.
 <WRAP center round help 100%>
-  * Describe the scenarios you used for assessing the impact of radio parameters on the ToA. You can join commented extracts of your code.
+  * Describe the scenarios you used for assessing the impact of the different parameters on the ToA.
-  * Visualise the experimental results using for example [[http://www.physics.csbsju.edu/stats/box2.html | box plots]] of the ToA as a function of the different radio parameters.
+  * Join commented extracts of your code and raw data in attached files.
-  * Analyze the obtained results and compare with the theoretical computations. You can superpose the theoretical results and the practical ones on the same graph.
+  * Visualise the experimental results by plotting the ToA as a function of each one of the different parameters.
+  * Analyze the obtained results and compare with the theoretical computations. You can superpose the theoretical results and the experimental ones on the same graph.
 </WRAP>
-==== -. 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.
+==== -. [Classroom activity] Collisions and Packet Delivery Ratio ====
-Only for this test, all groups are required to use the same frequency (for example 868.10 MHz).
+In this section, you will measure the Packet Delivery Ratio (PDR) under different transmission periods. Only for this test, all groups are required to use the same frequency, spreading factor, and coding rate.
+You will start by implementing a function on the server that measures the ratio of successfully delivered packets.
 <WRAP center round help 100%>
@@ Line 143: / Line 146: @@
 ==== -. Coverage ====
+In this section, you will measure the coverage of LoRa under the three different radio configurations. Such configurations should ensure different reliability levels.
-In this section, you will measure the coverage of LoRa devices under the three different radio configurations. For this, you can start by identifying a set of Test Points (TP) on the campus. Then, you should implement a function that sends packets with different radio configurations. Note that the following functions in the Arduino sketch enable to modify //on the fly// the LoRa parameters:
+For this, you will start by identifying a set of geographical locations or Test Points (TP). These TPs should be astutely chosen to challenge the limits of LoRa transmission. Then you should implement a function on the server that measures the ratio of successfully delivered packets or PDR.
-<code c++>
-rf95.setModemConfig(RH_RF95::Bw125Cr45Sf128);
-rf95.setModemConfig(RH_RF95::Bw31_25Cr48Sf512);
-rf95.setModemConfig(RH_RF95::Bw125Cr48Sf4096);
-</code>
 <WRAP center round help 100%>
   * Draw the test points on a map.
-  * Give a statistical measure of the PER and the RSSI for each TP with each of the different radio configurations.
+  * Give a statistical measure of the PDR and the RSSI for each TP with each of the different radio configurations.
 </WRAP>
 ==== -. Path Loss ====