Issue link: https://read.uberflip.com/i/1540208
Regional Parameters RP002-1.0.5 ©2022-2025 LoRa Alliance ® Page 41 of 116 The authors reserve the right to change specifications without notice. Devices that use an antenna system with a directional gain greater than 766 +6 dBi reduce the specified conducted output power by the amount in 767 dB of directional gain over +6 dBi. 768 769 US902-928 end-devices SHALL be capable of operating in the 902 to 928 MHz frequency 770 band and SHALL feature a channel data structure to store the parameters for a minimum of 771 72 and a maximum of 80 channels. This channel data structure contains a list of frequencies 772 and the set of data rates available for each frequency. 773 If using the over-the-air activation procedure, the end-device SHALL transmit the Join- 774 Request message on a random 125 kHz channels amongst the 64 channels defined using 775 uplink DR0 and on 500 kHz channels amongst the 8 channels defined using uplink DR4. The 776 end-device SHALL change channels for every transmission. 777 For rapid network acquisition in mixed gateway channel plan environments, the device 778 SHOULD follow a random channel selection sequence that efficiently probes the octet groups 779 of eight 125 kHz channels, followed by probing one 500 kHz channel on each pass. Each 780 consecutive pass SHOULD NOT select a channel that was used in a previous pass, until a 781 Join-Request is transmitted on every channel, after which the entire process can restart. 782 Example: 783 First pass: Random channel from [0-7], followed by [8-15] … [56-63], 784 then 64. 785 Second pass: Random channel from [0-7], followed by [8-15] … [56-63], 786 then 65. 787 Last pass: Random channel from [0-7], followed by [8-15] … [56-63], 788 then 71. 789 Personalized devices SHALL have all 72 channels enabled following a reset and SHALL use 790 the channels for which the device's default data-rate is valid. 791 3.5.3 US902-928 Data Rate and End-Device Output Power Encoding 792 For frequency hopping systems, FCC regulations impose a maximum dwell time of 400ms on 793 uplinks when the 20dB modulation bandwidth is less than 500 kHz. The TxParamSetupReq 794 MAC command is not implemented by US902-928 devices. 795 The following encoding is used for Data Rate (DR) in the US902-928 band: 796 797 Uplink Data Rate Configuration Indicative Physical Bit Rate [bit/sec] 0 LoRa: SF10 / 125 kHz 980 1 LoRa: SF9 / 125 kHz 1760 2 LoRa: SF8 / 125 kHz 3125 3 LoRa: SF7 / 125 kHz 5470 4 LoRa: SF8 / 500 kHz 12500 5 LR-FHSS CR1/3: 1.523 MHz BW 162 6 LR-FHSS CR2/3: 1.523 MHz BW 325 7 LoRa: SF6 / 125 kHz 9375 8 LoRa: SF5 / 125 kHz 15625 9..14 RFU 15 Defined in [TS001] 3 Table 19: US902-928 uplink data rates 798 799