Per the topic, has anyone successfully deployed NPR to extend the internet to a remote repeater node? I am looking at doing this with 5GHz AREDN, but NPR would be much easier if it works as I have some pesky trees in the way that block the microwave path. Thx. 73, Adrian VE7NZ
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I am also interested in this possibility, but I plan to use SX1280 (LoRa). There are two possible scenarios. The first scenario is the connection of voting receivers to node (one-way simplex transmission). This requires a device based on PIC, AVR or ESP32, which will connect to the AF output of the receiver, measure the signal to noise ratio, encode audio to g.711 and stream this data through the SX1280 (assume DATARADIO AUDIO INTERFACE). From the host side, the same device should receive the stream and feed it to the host via USB (assume DATARADIO USB INTERFACE). The host needs a module similar to chan_usbradio, chan_simpleusb or chan_voter that will receive this stream and feed it to app_rpt for comparison with signals from other receivers. (Assume chan_dataradio.) The second scenario involves linking nodes in a two-way mode. In this case, you can either use the SX1280 to organize communication via TCP / IP (in the case of NPR, you will have to use TCP / IP over AX25). Such a connection involves a significant overhead (AX25+IP+TCP+IAX), so you can use the same chan_dataradio to connect the node to remote node or radio. In this case, on a host installed at home and having an Internet connection, you can create a node (assume 2500) that would connect to other ASL nodes, and as a radio interface, this node should use DATARADIO USB INTERFACE that will transmit the audio stream to DATARADIO AUDIO INTERFACE connected to the radio or repeater installed at the remote site. In theory, in this embodiment, it is possible to implement not just two-way, but also duplex connection, if the modem bandwidth allows (SX1280 allows). Ideally, I would like to have a third option that would allow organizing routable connections between nodes via USB DATARADIO INTERFACE using a protocol designed to work through DATARADIO and replacing IAX2, which is not optimal for such configurations. But in this case, you need a proxy server that would handle incoming and outgoing IAX connections and redirect them from the IAX trunk to USB DATA RADIO and back. In this case, the task becomes more complicated, since the protocol used by USB DATA RADIO in this case should not only provide one-way or two-way duplex audio stream transmission, but also simultaneously transmit several audio streams and signaling from IAX2 to several nodes at once. With all the difficulties, the implementation of such functionality could transform repeater linking networks, making them, if not completely then at least partially independent of the Internet and capricious broadband wireless connections.