update readme

README.md

@@ -41,11 +41,20 @@ Research for each of does modules has to be done
 
 ### research
 
+#### cost estimation
+
+| Unit        | Price |
+|-------------|:-----:|
+| NEO-6M GPS  | 12.50 |
+| LoRa Module | 20.00 |
+| MCU         |       |
+| UAU         | 8.00  |
+
 #### MCU
 
 #### Communication Unit
 
-**software libraries:**
+##### software libraries:
 * [RFM69](https://github.com/LowPowerLab/RFM69)
   * pro:
   * con: 
@@ -65,17 +74,32 @@ Research for each of does modules has to be done
 * [ ] Checkout LoRa Modules/Lib
 * [ ] Checkout CC1101
 
-**protocoll research**
-Lora:
+##### protocoll research
+
+###### LoRa/LoRaWAN:
 * [Lange Funkstrecken mit Arduino, LoRaWAN/RFM95W und The Things Network](https://www.youtube.com/watch?v=vWLpbNqdNU0&ab_channel=BitBastelei)
   * deutschland legal 868mhz
   * diy antenne: 8.64cm blanker draht
 * gibt schon gateways bei thethingsnetwork.org
 * anscheinend muss man sihc registrieren um es nutzen zu koennen
 * an sich cool da man vorhandene gateways nutzen kann, schoen waere aber auch komplett eigene infrastruktur
+* man kann auch private netzwerke erstellen indem man eigenen lorawan gateway hostet, z.b. [auf einen raspberry](https://news.rakwireless.com/how-to-build-a-lorawan-gateway-make-your-own/)
+
+``` text
+It does not support the Mesh topology:
+Although it is long-range, it is impossible to extend the distance or get over geographic obstruction using other nodes as a repeater (like XBee, Wirepas or Bluetooth 5 Mesh). It was designed based on the original concept of ALOA 1971.
+```
+
+
+###### DigiMesh:
+* proprietary wireless mesh... proprietary.. yuck
 
 #### GPS Unit
 
 #### User Access Unit
 
 
+### DevEnv
+
+arduino and nixos. to let arduino access serial device it seems like the user should be added to the 'dialout' group
+