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exploring_lora [2018/10/06 13:51] – [3.1. Modifying the Radio Parameters] samerexploring_lora [2018/10/06 14:49] – [Table] samer
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 </code> </code>
  
-In order to reduce collisions, configure the central frequency of your LoRa devices as indicated below:+In order to reduce collisions between simultaneous experiments, configure the central frequency of your LoRa devices as indicated below:
  
 ^  Group Number  ^   Frequency     ^ ^  Group Number  ^   Frequency     ^
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 |       11            868.7      | |       11            868.7      |
 |       12            868.9      | |       12            868.9      |
- 
 ==== -. Running Basic Sketches ==== ==== -. Running Basic Sketches ====
  
-Now you can compile and upload the client and server sketches on the two arduino devices, respectively. On the serial interfaces, you should obtain similar results as in Fig. 2 and Fig. 3. The client sends periodically a short message towards the server. The server outputs the RSSI (received power in dBm) for each received message.+Now you can compile and upload the client and server sketches on the two arduino devices, respectively. On the serial interfaces, you should obtain similar results as in Fig. 2 and Fig. 3. The client sends periodically a short packet towards the server. The server outputs the RSSI (received power in dBm) for each received packet.
  
 [{{ :client-iotlab1.png?direct&600 ||Figure 2. Client serial monitor}}] [{{ :client-iotlab1.png?direct&600 ||Figure 2. Client serial monitor}}]
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 ==== -. Time on Air ==== ==== -. Time on Air ====
  
-In this section, you will measure the Time on Air (ToA) that is 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 message size on the ToA.+In this section, you will measure the Time on Air (ToA) that is given by the time necessary to transmit a packet on the radio interface. You will assess the impact of the spreading factor, bandwidth, coding rate, and packet size on the ToA.
  
-Start by implementing a function on the client that measures the time necessary for sending a messageFor 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 experiment multiple times in order to obtain the statistical distribution.+Start by implementing a function on the client that measures the time necessary for sending a packetYou can have recourse to 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, packet size) and record the impact on the ToA. Note well that you may need to repeat the experiment multiple times in order to obtain the statistical distribution
 + 
 +For example, the scenario for assessing the impact of the spreading factor on the ToA consists of sending 100 packets for three different spreading factors //e.g.,// 7, 9, and 10, and drawing the average ToA or the distribution in a boxplot for comparing the results.
  
 <WRAP center round help 100%> <WRAP center round help 100%>
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 The setting for this experiment is unique: The setting for this experiment is unique:
- 
   * Only one server is required in the classroom. This server should compute the ratio of successfully delivered packets or PDR.   * Only one server is required in the classroom. This server should compute the ratio of successfully delivered packets or PDR.
   * All groups are required to use the same frequency, spreading factor, and coding rate.   * All groups are required to use the same frequency, spreading factor, and coding rate.
-  * On each client, packets will be generated following a Poisson process with the same average arrival rate for all groups+  * The average packet arrival rate is equal for all clients. The delay between two packets is drawn uniformly in a predefined interval.
  
 <WRAP center round help 100%> <WRAP center round help 100%>
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   * Provide the expression of the link budget and compute the received power using two different pathloss models.   * Provide the expression of the link budget and compute the received power using two different pathloss models.
   * Compare the received power obtained experimentally with the theoretical results.   * Compare the received power obtained experimentally with the theoretical results.
-  * Write an article (blog, wiki, ...) to describe your experiment.+  * Prepare a short presentation to describe your experiment
 +</WRAP> 
 + 
 +<WRAP center round important 75%> 
 +This challenge and the corresponding grading is considered as a part of the final project.
 </WRAP> </WRAP>
 ===== -. Grading ===== ===== -. Grading =====
  
-                         ^ Exemplary            ^ Accomplished       ^ Developing         ^ Beginning          +                              ^ Exemplary                                                                                                                                                                                  ^ Accomplished                                                                                                                                          ^ Developing                                                                                                                             ^ Beginning                                                                                                                                               
-Answer to questions                                                                                    +Written communication skills  Students provided an organized and thouroughly proof-read document with appropriate structure and formatting (figure labels, headings, references, graphs, etc.), and relevant semantics.  Students provided an organized document with appropriate structure, and relevant semantics, containing minor misspellings and/or grammatical errors.  Students provided a document with appropriate structure, and poor semantics, containing minor misspellings and/or grammatical errors.  Students provided a document with inappropriate structure and formatting, and poor semantics, containing major misspellings and/or grammatical errors.  
-Design experiments                                                                                     +Scientific referencing (5%)   Original work. Proper referencing of material (parts/sentences/figures) quoted from relevant sources.                                                                                      Original work. Proper referencing of material (parts/sentences/figures).                                                                              Proper referencing of quoted material (parts/sentences/figures) but over-reliance on external sources.                                 All copied material (parts/sentences/figures) from other sources is not referenced. Reports cannot be submitted as is and must be rewritten.            
-^ Analyse results                                                                                        |+^ Analyse results                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
exploring_lora.txt · Last modified: 2021/10/20 12:52 by samer