sebastian
/
wspr-beacon
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Update 'WSPR Message Coding'

Sebastian 2021-05-06 21:48:35 +00:00
parent 3d4896e708
commit 2b85f93d73
1 changed files with 20 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
WSPR-Message-Coding.md

@ -20,3 +20,23 @@ and `nu = msg_type % 10`:
* Message with a 15bit hash call sign
* 6 Character locator
* Power is `-msg_type - 1`
Two common usecases:
1. Alternating between standard messages and messages with extended locators. Usually used to give a more precise position e.g. for moving mobile stations.
2. Alternating between message with prefixed call signs and messages with extended locators.
If you have to use prefix, this is the only way to transmit your full call sign and a locator.
The prefix will also be part of the hash so your messages can be matched.
Standard Message
-------------------------
Explained quite well in [The WSPR Coding Process](http://g4jnt.com/WSPR_Coding_Process.pdf) by G4JNT.
Prefixed Callsign Message
------------------------------------
**TODO**
Exetended Locator Message
---------------------------------------
Hash function use for the call sign is `hashlittle` from [lookup3.c](http://burtleburtle.net/bob/c/lookup3.c) one of the [Jenkins hash functions](https://en.wikipedia.org/wiki/Jenkins_hash_function).
The hash function is applied to the complete call sign including any prefix or suffix.