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Last modified by Xiaoling on 2025/05/05 08:51
From version 2.1
edited by Xiaoling
on 2022/05/11 14:19
Change comment: There is no comment for this version
To version 4.3
edited by Xiaoling
on 2022/05/11 14:35
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  
... ... @@ -84,13 +84,17 @@
84 84  
85 85  CN470 Channels
86 86  
109 +(((
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.
111 +)))
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  
91 91  TTN FREQUENCY PLAN
92 92  
117 +(((
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. )
119 +)))
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  
130 +(((
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.
132 +)))
105 105  
134 +(((
135 +
136 +)))
137 +
138 +(((
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.
140 +)))
107 107  
108 108  
109 109  = 4. Transmision on ABP Mode =
110 110  
145 +(((
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.
147 +)))
112 112  
149 +(((
150 +
151 +)))
152 +
153 +(((
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.
155 +)))
114 114  
157 +(((
158 +
159 +)))
160 +
161 +(((
115 115  To solve this, disable the Frame Counter Check will solve this issue , or reset the frame counter in the device page.
163 +)))
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  
176 +(((
128 128  Depends on Class A or Class C, the receive windows will be a little difference,
178 +)))
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  
... ... @@ -152,7 +152,9 @@
152 152  Set a downstream in TTN and see it is sent
153 153  
154 154  
205 +(((
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
207 +)))
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  
... ... @@ -161,7 +161,9 @@
161 161  
162 162  **For LoRaWAN Gateway**
163 163  
216 +(((
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:
218 +)))
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  
... ... @@ -172,28 +172,43 @@
172 172  
173 173  we can use AT Command (AT+CFG) to check the RX1 configure and RX2 configure. as below:
174 174  
229 +(% class="box infomessage" %)
175 175  (((
176 -{{info}}
177 -{{{AT+RX2FQ=869525000 ---> The RX2 Window frequency
178 -AT+RX2DR=3 ---> The RX2 DataRate
179 -AT+RX1DL=1000 ---> Receive Delay 1
180 -AT+RX2DL=2000 ---> Receive Delay 2}}}
181 -{{/info}}
231 + AT+RX2FQ=869525000 ~-~--> The RX2 Window frequency
232 +)))
182 182  
183 -
234 +(% class="box infomessage" %)
235 +(((
236 + AT+RX2DR=3 ~-~--> The RX2 DataRate
184 184  )))
185 185  
239 +(% class="box infomessage" %)
240 +(((
241 + AT+RX1DL=1000 ~-~--> Receive Delay 1
242 +)))
243 +
244 +(% class="box infomessage" %)
245 +(((
246 + AT+RX2DL=2000 ~-~--> Receive Delay 2
247 +)))
248 +
186 186  when the device running, we can see below info:
187 187  
188 -{{{[12502]***** UpLinkCounter= 0 *****
251 +(% class="box" %)
252 +(((
253 +[12502]~*~*~*~** UpLinkCounter= 0 ~*~*~*~**
189 189  [12503]TX on freq 868500000 Hz at DR 0
190 190  [13992]txDone
191 -[15022]RX on freq 868500000 Hz at DR 0 --> RX1 window open at frequency: 868500000, DR0, after 15022-13992= 1030ms of txdone
192 -[15222]rxTimeOut --> no packet arrive in RX1 window. (duration: 200ms)
193 -[15987]RX on freq 869525000 Hz at DR 3 --> RX2 window open at frequency: 869525000, DR3, after 15987-13992= 1995ms of txdone
194 -[16027]rxTimeOut --> no packet arrive in RX2 window. (duration: 40 ms)
195 -}}}
256 +[15022]RX on freq 868500000 Hz at DR 0     ~-~-> RX1 window open at frequency: 868500000, DR0, after 15022-13992= 1030ms of txdone
257 +[15222]rxTimeOut                           ~-~-> no packet arrive in RX1 window. (duration: 200ms)
258 +[15987]RX on freq 869525000 Hz at DR 3     ~-~-> RX2 window open at frequency: 869525000, DR3, after 15987-13992= 1995ms of txdone
259 +[16027]rxTimeOut                           ~-~-> no packet arrive in RX2 window. (duration: 40 ms)
260 +)))
196 196  
262 +(((
263 +
264 +)))
265 +
197 197  {{{Another message:
198 198  [12502]***** UpLinkCounter= 0 *****
199 199  [12503]TX on freq 868100000 Hz at DR 0
... ... @@ -216,7 +216,6 @@
216 216  * Gateway traffic (from server UI) to shows the data exchange between gateway and server.
217 217  * End Node traffic (from server UI) to shows end node activity in server.
218 218  
219 -
220 220  = 6. Downlink Issue ~-~- Packet REJECTED, unsupported frequency =
221 221  
222 222  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.
... ... @@ -310,4 +310,5 @@
310 310  * Solution: Use the decoder to filter out this 00 packet.
311 311  * Some node decoders may not have filtering function, or you need decoders of other servers and formats. Please send an email to david.huang@dragino.cc
312 312  
313 -== ==
381 +(% class="wikigeneratedid" id="H" %)
382 +