Issue link: https://read.uberflip.com/i/1479525
LoRaWAN® Regional Parameters RP002-1.0.4 ©2022 LoRa Alliance ® Page 91 of 101 The authors reserve the right to change specifications without notice. Example: This is a valid EU868 beacon frame (SF9): 1841 1842 Field RFU Param Time CRC InfoDesc Lat Lng CRC Value Hex 00 00 CC020000 7EA2 0 002001 038100 55DE Table 102: Example of beacon CRC calculation (SF9) 1843 Example: Over the air, the octets are sent in the following order: 1844 00 00 | 00 00 02 CC | A2 7E | 00 | 01 20 00 | 00 81 03 | DE 55 1845 The first CRC is calculated on [00 00 00 00 02 CC]. 1846 The OPTIONAL gateway-specific part provides additional information regarding the gateway 1847 sending a beacon and therefore can differ for each gateway. The OPTIONAL part is protected 1848 by a CRC-16 computed on the GwSpecific + RFU fields. The CRC-16 definition SHALL 1849 be the same as for the mandatory part. 1850 Example: This is a valid US915 beacon (SF12): 1851 1852 Field RFU Param Time CRC InfoDesc Lat Lng RFU CRC Value Hex 0000 00 CC020000 7EA2 00 002001 038100 00 D450 Table 103: Example of beacon CRC calculation 1853 Example: Over the air, the octets are sent in the following order: 1854 00 00 00 | 00 00 02 CC | A2 7E | 00 | 01 20 00 | 00 81 03 | 00 | 50 D4 1855 4.2 FSK Description 1856 4.2.1 FSK Packet Physical Structure 1857 FSK messages can be built either by the software stack or by the hardware transceiver, 1858 depending on the end-device architecture. 1859 The PHYPayload length field contains the length in bytes of the PHYPayload field. 1860 The CRC field is computed on PHYPayload length and PHYPayload fields, using the CRC- 1861 CCITT algorithm. 1862 PHY: 1863 Size (bytes) 5 3 1 L bytes from PHYPayloadLength 2 Packet Structure Preamble SyncWord PHYPayloadLength PHYPayload CRC Table 104: FSK PHY structure 1864 4.2.2 FSK Settings 1865 In order to be fully compliant with LoRaWAN, an end-device SHALL configure the FSK 1866 physical layer as follows: 1867 Parameter Uplink Value Downlink Value Preamble size 5 bytes SyncWord 0xC194C1 Bitrate 50000 bit/sec Tx frequency deviation 25 kHz (SSB 37 ) Rx bandwidth 50 kHz (SSB) Rx bandwidth AFC 80 kHz (SSB) CRC presence True (CRC-16-CCITT) 37 SSB: Single-Side Bandwidth