222 commits

Author	SHA1	Message	Date
Thomas Kolb	c1af786a70	WIP: handle packets from the TUN device in digipeater ... This is only a backup commit.	2024-11-10 23:13:54 +01:00
Thomas Kolb	61814584a2	tundev: remove IFF_NO_PI ... Without this flag the kernel adds packet information to each packet. The interesting part of that information is the EtherType of the packet, which simplifies handling.	2024-11-10 23:10:32 +01:00
Thomas Kolb	49fe1fff29	l2udptest_client: fix compilation	2024-11-10 21:40:07 +01:00
Thomas Kolb	4862c09bdd	connection: calculate IPv6 address for peer	2024-11-10 21:39:15 +01:00
Thomas Kolb	e44cfb722d	Add missing call to digipeater_end_interval()	2024-11-10 21:01:13 +01:00
Thomas Kolb	3a8f469e8e	digipeater: add one-shot packet queue and interval handling ... The oneshot queue is for connection management frames that are only sent once, at the beginning of the next burst. An example is the Connection Reset packet. Intervals define the boundary between the handling of different connections. The interval can be either ended by a packet with TX Request set, or by a timeout. In either case, forwarding of packets to the current connection stops and the connection is re-scheduled to a later point in time.	2024-11-10 20:18:10 +01:00
Thomas Kolb	93d74be000	WIP: managing multiple connections ... Working towards handling multiple connections. A lot is still missing.	2024-11-10 17:02:14 +01:00
Thomas Kolb	31a627d434	WIP: digipeater module managing multiple connections ... Backup commit. This is a basic setup with lots of TODOs and errors. Will not compile yet.	2024-11-03 14:40:11 +01:00
Thomas Kolb	bfdb174324	l2/connection: refactoring ... - split handle_packet() in two functions: the first does basic checks and calls the second one. This allows to do the basic checks externally (in the multi-connection management module) without duplicating them. - use the new layer2_encode_packet() function.	2024-11-03 14:35:01 +01:00
Thomas Kolb	0345dc589b	l2/packet_structs: add function to encode a complete packet	2024-11-03 14:34:03 +01:00
Thomas Kolb	8c79185df6	Handle retransmits inside the connection module	2024-11-02 20:20:39 +01:00
Thomas Kolb	c4e6028d42	Add a module to manage a list of connections	2024-11-02 18:30:25 +01:00
Thomas Kolb	03912a6185	Do all time calculations in uint64_t ... This prevents loss of precision that occurs with double-precision floats if timestamps become very large. Timestamps are already large if they contain a UNIX time value (requires 60 bits; double has 53 bit resolution).	2024-11-02 16:17:52 +01:00
Thomas Kolb	4281ae4be7	l2udptest: replace by two programs: client and digipeater ... Both are identical so far, this is just an infrastructure commit.	2024-11-02 16:07:25 +01:00
Thomas Kolb	04397c2c95	Remove empty packet from queue after burst was transmitted	2024-09-22 18:46:32 +02:00
Thomas Kolb	8c3eca658c	connection: do not send ACKs for empty packets	2024-09-22 15:56:43 +02:00
Thomas Kolb	dedad8b81f	connection: handle ACKs from empty packets correctly	2024-09-22 15:52:44 +02:00
Thomas Kolb	f0770baf31	Handle received packets	2024-09-22 15:34:50 +02:00
Thomas Kolb	a07ffa265e	connection: use correct addresses for empty packets	2024-09-22 15:28:24 +02:00
Thomas Kolb	0a77109ab5	l2udp: Use the new layer2 connection module	2024-09-22 15:24:20 +02:00
Thomas Kolb	85ec105d0f	Pass received packets to layer 2 processing	2024-09-22 14:45:24 +02:00
Thomas Kolb	ec6dd92444	Basic infrastructure for layer2-over-udp test	2024-09-22 14:32:49 +02:00
Thomas Kolb	a455fac050	connection.h: fix comment	2024-09-20 23:38:54 +02:00
Thomas Kolb	44921bd65d	Decrease the AGC bandwidth during signal acquisition ... This prevents rapid squelch activation/deactivation if only noise is present. The AGC bandwidth was tuned such that it still allows preambles to be detected reliably.	2024-09-20 23:10:49 +02:00
Thomas Kolb	ccd9af6664	Delay squelch activation by 2 ms ... Delaying the squelch activation by 2 ms helps to avoid dropped samples if the signal is barely above the squelch threshold.	2024-09-20 23:08:43 +02:00
Thomas Kolb	4dc2c60c8b	rx: reduce squelch threshold from 10 to 6 dB ... During tests it was determined that this is much more reliable. The theory is that the first packet of a burst was frequently not detected because the squelch opened too late if the channel was very noisy. Unfortunately, the squelch now opens very often even if no signal is present. This will be improved in the future.	2024-09-12 23:52:33 +02:00
Thomas Kolb	706a1eb437	freq_est: make ramp-up delta phase check more strict ... This should help with occasional jumps in the estimated carrier frequency on receivers running frequency tracking.	2024-09-12 23:49:57 +02:00
Thomas Kolb	eb802629a1	layer1/rx: calculate EVM during header and data reception	2024-09-07 00:48:11 +02:00
Thomas Kolb	79c340c20d	connection: add state checks	2024-08-25 23:27:22 +02:00
Thomas Kolb	fc9e5c5229	Combine layer2_rx and layer2_tx in a new connection module ... The new module is not used yet, but this is a preparation for the future multi-client networking support.	2024-08-25 22:26:56 +02:00
Thomas Kolb	899152a530	Remove config.h from Git; must be adapted by the user ... A template for the config file is provided in src/config.h.template. It must be copied to src/config.h and adapted for force users to set their own station call sign.	2024-08-25 20:26:41 +02:00
Thomas Kolb	c52d0766d7	Remove obsolete compile_flags.txt	2024-08-23 19:52:24 +02:00
Thomas Kolb	2e91fd7c42	Apply free software+documentation licenses ... All code is now licensed under GPLv3+. The documentation is licensed under CC BY-SA 4.0. This is now officially free software! \o/	2024-08-23 11:53:40 +02:00
Thomas Kolb	017eb221f1	Integrate the interleaver	2024-08-16 22:14:07 +02:00
Thomas Kolb	325abdbd02	packet_queue: allow max. 15 packets to be queue (transmit window) ... 16 is not allowed because it leads to an overflow in sequence numbers, making them ambiguous.	2024-08-09 22:22:01 +02:00
Thomas Kolb	6d9068f63d	define INTERLEAVE_DISTANCE	2024-08-09 22:18:20 +02:00
Thomas Kolb	2ddb8aa18c	Randomize retransmit time	2024-08-09 22:16:14 +02:00
Thomas Kolb	d2ef6d9741	Remove empty packets from the queue after their first transmission	2024-07-27 00:50:04 +02:00
Thomas Kolb	04dcfff6fd	Do not transmit an empty packet if an empty packet was received	2024-07-27 00:33:47 +02:00
Simon Ruderich	9990aa5fbb	main: check return value of layer2_tx_fill_packet_queue()	2024-07-24 20:20:36 +02:00
Simon Ruderich	52f45cb433	layer2: check return values when adding empty packets	2024-07-24 20:20:36 +02:00
Simon Ruderich	4e2815923c	layer2: handle invalid message types just in case	2024-07-23 09:24:32 +02:00
Simon Ruderich	766caf7e07	layer2/packet_structs: use variable to reduce duplication	2024-07-23 09:15:56 +02:00
Simon Ruderich	b3a49fe0ba	layer2: update comments, use constant	2024-07-23 09:15:34 +02:00
Simon Ruderich	8aacbaf8c3	layer2/packet_queue: remove unused function packet_queue_can_add_packet()	2024-07-23 08:41:42 +02:00
Simon Ruderich	9845514a46	layer2/packet_queue: permit using full queue size ... Previously, only PACKET_QUEUE_SIZE - 1 elements could be stored.	2024-07-23 08:41:25 +02:00
Thomas Kolb	10a869d1a2	Layer 2: send Empty Packet acknowledgements if there’s nothing else to transmit	2024-07-22 22:19:23 +02:00
Thomas Kolb	c9916c08da	Add a simple interleaver implementation (not used yet)	2024-07-21 17:23:15 +02:00
Thomas Kolb	04f29b94bf	rx: show AGC gain after preamble, header and data	2024-07-20 22:33:08 +02:00
Thomas Kolb	576cdbfac5	Added ham64.c/.h to CMakeLists.txt	2024-07-20 22:32:01 +02:00