Last modified by Mengting Qiu on 2024/01/29 19:33
<
From version < 4.1 >
edited by Xiaoling
on 2022/05/11 14:26
To version < 4.3 >
edited by Xiaoling
on 2022/05/11 14:35
>
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... ... @@ -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 +(((
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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.
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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.
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114 114  
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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,
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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  
... ... @@ -174,35 +174,41 @@
174 174  
175 175  (% class="box infomessage" %)
176 176  (((
177 -AT+RX2FQ=869525000 ~-~--> The RX2 Window frequency
231 + 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
236 + AT+RX2DR=3 ~-~--> The RX2 DataRate
183 183  )))
184 184  
185 185  (% class="box infomessage" %)
186 186  (((
187 -AT+RX1DL=1000 ~-~--> Receive Delay 1
241 + AT+RX1DL=1000 ~-~--> Receive Delay 1
188 188  )))
189 189  
190 190  (% class="box infomessage" %)
191 191  (((
192 -AT+RX2DL=2000 ~-~--> Receive Delay 2
246 + AT+RX2DL=2000 ~-~--> Receive Delay 2
193 193  )))
194 194  
195 195  when the device running, we can see below info:
196 196  
197 -{{{[12502]***** UpLinkCounter= 0 *****
251 +(% class="box" %)
252 +(((
253 +[12502]~*~*~*~** UpLinkCounter= 0 ~*~*~*~**
198 198  [12503]TX on freq 868500000 Hz at DR 0
199 199  [13992]txDone
200 -[15022]RX on freq 868500000 Hz at DR 0 --> RX1 window open at frequency: 868500000, DR0, after 15022-13992= 1030ms of txdone
201 -[15222]rxTimeOut --> no packet arrive in RX1 window. (duration: 200ms)
202 -[15987]RX on freq 869525000 Hz at DR 3 --> RX2 window open at frequency: 869525000, DR3, after 15987-13992= 1995ms of txdone
203 -[16027]rxTimeOut --> no packet arrive in RX2 window. (duration: 40 ms)
204 -}}}
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 +)))
205 205  
262 +(((
263 +
264 +)))
265 +
206 206  {{{Another message:
207 207  [12502]***** UpLinkCounter= 0 *****
208 208  [12503]TX on freq 868100000 Hz at DR 0

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