Differences

This shows you the differences between two versions of the page.

--- l1_comm [2018/09/27 11:24] – alberto
+++ l1_comm [2023/09/06 11:21] (current) – external edit 127.0.0.1
@@ Line 6: / Line 6: @@
 intended as a fallback solution in case of failure of the level 2 system. Iridium is the only satellite communication system provider with global coverage and is known for high-reliability. The selected Iridium transceiver is for short burst data (SBD) and will allow for reporting of parameters such as the state of the onboard systems and the USVs position, but also the ability for the remote operator to send simple commands to the onboard
 system. The short range radio system will be used for manual control of the USV during launch and retrieval.
-{{:l1-comm.png?1000|}}
 \\
 \\
-=======Short-range Communication===========
+=======Long-range Radio Communication===========
-Short-range communication happens through the 433 MHz Radio Transceiver. The operator is able to send commands encoded in NMEA format. The messages the Operator can send to Level 1 respect this format:
+Direct communication for telemetry happens through the OWL radios. The operator is able to send commands encoded in NMEA format. The messages the Operator can send to Level 1 respect this format:
 \\
 ;#;
@@ Line 27: / Line 25: @@
 - FALLB_MODE selects the fallback mode: 0 for //rudder 0//, 1 for //circle//, 2 for //autopilot//; \\
 - MANUAL_CTRL is a boolean: 1 for taking control (manual), 0 for giving control (autopilot).
+\\
+| {{ :owldatasheet.pdf |OWL VHF datasheet}}      | Owl VHF datasheet.|
+| http://skagmoelectronics.com/      | OWL VHF Webpage.|
+The Owl VHF is a small, yet high performance radio transceiver packed with features. It's very flexible internal architecture allows a wide variety of modulation types and encoding. Rather than the typical SDR approach where samples are processed by an external device, the Owl does all its processing internally.	A large command set regarding modulation, encoding and user protocol is configured through a serial port.
+\\
+;#;
+{{:owl.png?400|}}
+;#;
 \\
@@ Line 46: / Line 54: @@
 When the Campbell Scientific C6 computer sends a message to the RockBlock device, the message is loaded into the so-called mobile originated message buffer in the device. A message transfer session between the RockBlock and the gateway SBD subsystem is then initiated. The RockBlock will notify the CR6 on the success of the message. If the RockBlock receives a message, it will be stored in the mobile terminated buffer in the device and can be transferred to the CR6 via the serial interface.
 The communication between the Iridium unit in the rock block and the CR6 level 1 computer follows an Iridium proprietary protocol that is described in a document called ISU AT Command Reference. A total of 180 commands are described, in which roughly 50 are supported by the Iridium 9602 transceiver. Out of those commands, 20 concern the handling of short burst data service. After assessing the different functions and possibilities, the following instructions were selected for implementation:\\
-\\
-- SBDI (Short Burst Data Initiate);
+- SBDI (Short Burst Data Initiate);\\
-- SBDRT (Short Burst Data Read Text);
+- SBDRT (Short Burst Data Read Text);\\
-- SBDRB (Short Burst Data Read Binary);
+- SBDRB (Short Burst Data Read Binary);\\
-- SBDS (Status);
+- SBDS (Status);\\
-- SBDTC (Transfer MO to MT);
+- SBDTC (Transfer MO to MT);\\
-- SBDWB (Write binary);
+- SBDWB (Write binary);\\
 - SBDWT (Write text).
+| {{ :rockblock.pdf |RockBlock+}}      | RockBlock+ Brochure.|
+| https://www.rock7.com/products-rockblock-plus      | RockBlock+ Webpage.|
+The RockBLOCK device is IP68 rated and hosts an Iridium 9602 unit, an antenna and a voltage regulator. The 9602 unit is interfaced with RS-232 using AT commands. Depending on the conditions, the unit can send or receive a message approximately every 40 seconds. The cost is 0.1 to 0.05 GBP per 50-byte message, depending on the bundle that is bought. In addition, there is a 10 GBP line rental per month. The system has a limited bandwidth and is therefore only suitable for simple control monitoring or tracking applications. The maximum package sizes are 340 bytes for sending and 270 bytes for receiving. Although the latency is typically a few seconds, it may be as much as a minute or more.
+{{:iridium1.png?400|}} {{:iridium1_table.png?400|}}