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Last modified by Xiaoling on 2025/05/05 08:51
From version 3.1
edited by Xiaoling
on 2022/05/11 14:23
Change comment: There is no comment for this version
To version 4.6
edited by Xiaoling
on 2022/05/11 14:52
Change comment: There is no comment for this version

Summary

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Content
... ... @@ -1,4 +1,4 @@
1 -
1 +**~ Contents:**
2 2  
3 3  {{toc/}}
4 4  
... ... @@ -60,17 +60,39 @@
60 60  
61 61  = 2. Notice of US915/CN470/AU915 Frequency band =
62 62  
63 +(((
63 63  If user has problem to work with lorawan server in band US915/AU915/CN470, he can check:
65 +)))
64 64  
65 -* What **sub-band** the server support ?
66 -* What is the **sub-band** the gateway support ?
67 -* What is the **sub-band** the end node is using ?
67 +* (((
68 +What **sub-band** the server support ?
69 +)))
70 +* (((
71 +What is the **sub-band** the gateway support ?
72 +)))
73 +* (((
74 +What is the **sub-band** the end node is using ?
75 +)))
68 68  
77 +(((
69 69  All of above should match so End Node can properly Join the server and don't have packet lost.
79 +)))
70 70  
81 +(((
82 +
83 +)))
84 +
85 +(((
71 71  In LoRaWAN protocol, the frequency bands US915, AU915, CN470 each includes at least 72 frequencies. Many gateways support only 8 or 16 frequencies, and server might support 8 frequency only. In this case, the OTAA join time and uplink schedule is long and unpredictable while the end node is hopping in 72 frequencies, because the end node will send data in many frequency that the gateway or server doesn,t support.
87 +)))
72 72  
89 +(((
90 +
91 +)))
92 +
93 +(((
73 73  Here are the freuqency tables for these bands as reference:
95 +)))
74 74  
75 75  [[image:https://wiki.dragino.com/images/thumb/3/3f/US915_FRE_BAND-1.png/600px-US915_FRE_BAND-1.png||height="170" width="600"]]
76 76  
... ... @@ -82,15 +82,23 @@
82 82  
83 83  [[image:https://wiki.dragino.com/images/thumb/3/3a/CN470_FRE_BAND-1.png/600px-CN470_FRE_BAND-1.png||height="205" width="600"]]
84 84  
107 +(((
85 85  CN470 Channels
109 +)))
86 86  
111 +(((
87 87  If we look at the [[TTN network server frequency plan>>url:https://www.thethingsnetwork.org/docs/lorawan/frequency-plans.html]], we can see the US915 frequency band use the channel 8~~15.So the End Node must work at the same frequency in US915 8~~15 channels for TTN server.
113 +)))
88 88  
89 89  [[image:https://wiki.dragino.com/images/thumb/9/9a/US915_FRE_BAND-2.png/600px-US915_FRE_BAND-2.png||height="288" width="600"]]
90 90  
117 +(((
91 91  TTN FREQUENCY PLAN
119 +)))
92 92  
121 +(((
93 93  In dragino end node, user can use AT+CHE command to set what frequencies set the end node will use. The default settings for Dragino end node are preconfigure for TTN server, so use 8~~15 channels, which is **AT+CHE=2**. (AT+CHE=1 for first 8 channels, AT+CHE=2 for second 8 channels.. etc, and AT+CHE=0 for all 72 channels. )
123 +)))
94 94  
95 95  
96 96  = 3. Why i see data lost/unperiocially uplink data? Even the signal strength is good =
... ... @@ -101,18 +101,40 @@
101 101  * **Gateway** ~-~-> Use Sub-band2 (Channel 8,9,10,11,12,13,14,15) for Dragino Gateway. this is the default settings for dragino sensors.
102 102  * **LoRaWAN server** ~-~-> ChirpStack default installation and use Sub-band1, **enabled_uplink_channels=[0, 1, 2, 3, 4, 5, 6, 7]** in the file chirpstack-network-server.toml.
103 103  
134 +(((
104 104  When Sensor power on, it will use sub-band2 to join the network, the frequency matches the settings in gateway so all Join Request will be passed to the server for Join. Server will ask the sensor to change to Sub-band1 in the Join Accept downlink message. Sensor will change to sub-band1 for data upload. This cause the sensor and gateway have different frequencies so user see lost of most data or even no data.
136 +)))
105 105  
138 +(((
139 +
140 +)))
141 +
142 +(((
106 106  Use Subband2 as a default subband cause the sensor to have problem to work with the LoRaWAN server which use other subband, and use need to access to the end node to change the subband by console. that is not user frendily,. So since Dragino LoRaWAN Stack version DLS-005(release on end of 2020), we have changed the device to use All Subbands for OTAA join, for example, device will use the first frequency in Sub-Band1 as firt OTAA join packet, then use the first frequency in Sub-Band 2 , then first frequency in sub-band 3, and so on. LoRaWAN server will normally provide the required subband in the OTAA accept process, so end node will know what subband it use after join. If LoRaWAN server doesn't provide subband info in OTAA join, end node will use the subband which join success as the working subband. So the new method cause a longer OTAA Join time but will be compatible with all LoRaWAN server. And new method won't affect the normal uplink after Join Success.
144 +)))
107 107  
108 108  
109 109  = 4. Transmision on ABP Mode =
110 110  
149 +(((
111 111  In ABP mode, there is a Frame Counter Checks. With this check enabled, the server will only accept the frame with a higher counter. If you reboot the device in ABP mode, the device will start from count 0, so you won't be able to see the frame update in server.
151 +)))
112 112  
153 +(((
154 +
155 +)))
156 +
157 +(((
113 113  So in ABP mode, first check if the packet already arrive your gateway, if the packet arrive gatewat but didn't arrive server. Please check if this is the issue.
159 +)))
114 114  
161 +(((
162 +
163 +)))
164 +
165 +(((
115 115  To solve this, disable the Frame Counter Check will solve this issue , or reset the frame counter in the device page.
167 +)))
116 116  
117 117  [[~[~[image:https://wiki.dragino.com/images/thumb/1/19/ABP_Issue-1.jpg/600px-ABP_Issue-1.jpg~|~|height="340" width="600"~]~]>>url:https://wiki.dragino.com/index.php/File:ABP_Issue-1.jpg]]
118 118  
... ... @@ -125,7 +125,9 @@
125 125  
126 126  LoRaWAN End node will open two receive windows to receive the downstream data. If the downstream packets arrive the end node at these receive windows, the end node will be able to get this packet and process it.
127 127  
180 +(((
128 128  Depends on Class A or Class C, the receive windows will be a little difference,
182 +)))
129 129  
130 130  [[image:https://wiki.dragino.com/images/thumb/1/1a/Downstream_LoRaWAN-1.png/600px-Downstream_LoRaWAN-1.png||height="590" width="600"]]
131 131  
... ... @@ -141,95 +141,109 @@
141 141  
142 142  == 5.2 See Debug Info ==
143 143  
198 +(((
144 144  **For LoRaWAN Server**
200 +)))
145 145  
202 +(((
146 146  We can check if there is downlink message for this end node, use TTN for example:
204 +)))
147 147  
206 +(((
148 148  Configure a downstream to the end device
208 +)))
149 149  
150 150  [[image:https://wiki.dragino.com/images/thumb/8/82/Downstream_debug_1.png/600px-Downstream_debug_1.png||height="217" width="600"]]
151 151  
212 +(((
152 152  Set a downstream in TTN and see it is sent
214 +)))
153 153  
154 154  
217 +(((
155 155  This downstream info will then pass to the gateway downstream list. and include the DR which is used (SF9BW125) in EU868 is DR3
219 +)))
156 156  
157 157  [[image:https://wiki.dragino.com/images/thumb/d/dc/Downstream_debug_2.png/600px-Downstream_debug_2.png||height="245" width="600"]]
158 158  
223 +(((
159 159  Gateway Traffic can see this downstream info
225 +)))
160 160  
161 161  
228 +(((
162 162  **For LoRaWAN Gateway**
230 +)))
163 163  
232 +(((
164 164  When the downstream packet appear on the traffic of Gateway page. The LoRaWAN gateway can get it from LoRaWAN server and transmit it. In Dragion Gateway, this can be checked by runinng "logread -f" in the SSH console. and see below:
234 +)))
165 165  
166 166  [[image:https://wiki.dragino.com/images/thumb/2/21/Downstream_debug_3.png/600px-Downstream_debug_3.png||height="195" width="600"]]
167 167  
238 +(((
168 168  Gateway Sent out this packet
240 +)))
169 169  
170 170  
243 +(((
171 171  **For End Node**
245 +)))
172 172  
173 173  we can use AT Command (AT+CFG) to check the RX1 configure and RX2 configure. as below:
174 174  
175 175  (% class="box infomessage" %)
176 176  (((
177 -AT+RX2FQ=869525000 ~-~--> The RX2 Window frequency
251 + AT+RX2FQ=869525000 ~-~--> The RX2 Window frequency
178 178  )))
179 179  
180 180  (% class="box infomessage" %)
181 181  (((
182 -AT+RX2DR=3 ~-~--> The RX2 DataRate
256 + AT+RX2DR=3 ~-~--> The RX2 DataRate
183 183  )))
184 184  
185 185  (% class="box infomessage" %)
186 186  (((
187 -AT+RX1DL=1000 ~-~--> Receive Delay 1
261 + AT+RX1DL=1000 ~-~--> Receive Delay 1
188 188  )))
189 189  
190 190  (% class="box infomessage" %)
191 191  (((
192 -AT+RX2DL=2000 ~-~--> Receive Delay 2
266 + AT+RX2DL=2000 ~-~--> Receive Delay 2
193 193  )))
194 194  
269 +**when the device running, we can see below info:**
270 +
195 195  (((
196 -{{info}}
197 -(% class="box infomessage" %)
198 -(((
199 -AT+RX2FQ=869525000     ~-~--> The RX2 Window frequency
200 -AT+RX2DR=3  ~-~--> The RX2 DataRate
201 -AT+RX1DL=1000  ~-~--> Receive Delay 1
202 -AT+RX2DL=2000  ~-~--> Receive Delay 2
272 +
203 203  )))
204 -{{/info}}
205 205  
275 +{{{ [12502]***** UpLinkCounter= 0 *****
276 + [12503]TX on freq 868500000 Hz at DR 0
277 + [13992]txDone
278 + [15022]RX on freq 868500000 Hz at DR 0 --> RX1 window open at frequency: 868500000, DR0, after 15022-13992= 1030ms of txdone
279 + [15222]rxTimeOut --> no packet arrive in RX1 window. (duration: 200ms)
280 + [15987]RX on freq 869525000 Hz at DR 3 --> RX2 window open at frequency: 869525000, DR3, after 15987-13992= 1995ms of txdone
281 + [16027]rxTimeOut --> no packet arrive in RX2 window. (duration: 40 ms)}}}
282 +
283 +(((
206 206  
207 207  )))
208 208  
209 -when the device running, we can see below info:
287 +**Another message:**
210 210  
211 -{{{[12502]***** UpLinkCounter= 0 *****
212 -[12503]TX on freq 868500000 Hz at DR 0
213 -[13992]txDone
214 -[15022]RX on freq 868500000 Hz at DR 0 --> RX1 window open at frequency: 868500000, DR0, after 15022-13992= 1030ms of txdone
215 -[15222]rxTimeOut --> no packet arrive in RX1 window. (duration: 200ms)
216 -[15987]RX on freq 869525000 Hz at DR 3 --> RX2 window open at frequency: 869525000, DR3, after 15987-13992= 1995ms of txdone
217 -[16027]rxTimeOut --> no packet arrive in RX2 window. (duration: 40 ms)
218 -}}}
289 +{{{
290 + [12502]***** UpLinkCounter= 0 *****
291 + [12503]TX on freq 868100000 Hz at DR 0
292 + [13992]txDone
293 + [15022]RX on freq 868100000 Hz at DR 0
294 + [15222]rxTimeOut
295 + [15987]RX on freq 869525000 Hz at DR 3
296 + [16185]rxDone --> We have got the downstream packet.
297 + Rssi= -64
298 + Receive data
299 + 1:0012345678}}}
219 219  
220 -{{{Another message:
221 -[12502]***** UpLinkCounter= 0 *****
222 -[12503]TX on freq 868100000 Hz at DR 0
223 -[13992]txDone
224 -[15022]RX on freq 868100000 Hz at DR 0
225 -[15222]rxTimeOut
226 -[15987]RX on freq 869525000 Hz at DR 3
227 -[16185]rxDone --> We have got the downstream packet.
228 -Rssi= -64
229 -Receive data
230 -1:0012345678
231 -}}}
232 -
233 233  == 5.3 If problem doesn’t solve ==
234 234  
235 235  **If user has checked below steps and still can't solve the problem, please send us (support @ dragino.com) the sceenshots for each step to check. They include:**
... ... @@ -241,14 +241,29 @@
241 241  
242 242  = 6. Downlink Issue ~-~- Packet REJECTED, unsupported frequency =
243 243  
312 +(((
244 244  In LoRaWAN, the gatewat will use the frequency specify by the server to transmit a packet as downlink purpose. Each Frequency band has different downlink frequency. and the gateway has a frequency range limited to transmit downlink.
314 +)))
245 245  
316 +(((
317 +
318 +)))
319 +
320 +(((
246 246  So if the LoRaWAN server is an AS923 server which ask the gateway to transmit at 923.2Mhz frequency, but the gateway is IN868 frequency band (support 865~~867Mhz to transmit). In the gateway log it will show something like below:
322 +)))
247 247  
248 -{{{Sat Nov 21 08:04:17 2020 daemon.info lora_pkt_fwd[1680]: ERROR~ Packet REJECTED, unsupported frequency - 923200000 (min:865000000,max:867000000)
249 -}}}
324 +(((
325 +Sat Nov 21 08:04:17 2020 daemon.info lora_pkt_fwd[1680]: ERROR~~ Packet REJECTED, unsupported frequency - 923200000 (min:865000000,max:867000000)
326 +)))
250 250  
328 +(((
329 +
330 +)))
331 +
332 +(((
251 251  In this case, please double check the gateway frequency and the server frequency band.
334 +)))
252 252  
253 253  
254 254  = 7. Decrypt a LoRaWAN Packet =