Skip to Content
Last modified by Xiaoling on 2024/08/16 11:25
From version 10.5
edited by Xiaoling
on 2022/10/15 16:28
Change comment: There is no comment for this version
To version 24.1
edited by Xiaoling
on 2024/08/16 11:25
Change comment: There is no comment for this version

Summary

Details

Page properties
Content
... ... @@ -4,6 +4,8 @@
4 4  
5 5  
6 6  
7 +
8 +
7 7  = 1.  OverView =
8 8  
9 9  
... ... @@ -10,7 +10,6 @@
10 10  In real-world deployment for LoRa, distance is a common topic. We always want to have the longest distance. This chapter shows some instructions for how to improve this.
11 11  
12 12  
13 -
14 14  = 2.  Analyze at the software side =
15 15  
16 16  == 2.1  LoRa parameters that effect distance ==
... ... @@ -36,20 +36,18 @@
36 36  
37 37  **End node actually value when TXP=0 and DR=0**
38 38  
39 -(% border="1.5" cellspacing="4" style="background-color:#ffffcc; color:black; width:1002px" %)
40 -|(% style="width:134px" %)**Frequency band**|(% style="width:400px" %)**Output Power in LoRa Module (consider 2dB antenna)**|(% style="width:362px" %)(((
40 +(% border="1" cellspacing="3" style="background-color:#f2f2f2; width:1002px" %)
41 +|(% style="background-color:#4f81bd; color:white; width:134px" %)**Frequency band**|(% style="background-color:#4f81bd; color:white; width:400px" %)**Output Power in LoRa Module (consider 2dB antenna)**|(% style="background-color:#4f81bd; color:white; width:362px" %)(((
41 41  **Spreading Factor(Higher SF can transmit further)**
42 -)))|(% style="width:102px" %)**Band Width**
43 +)))|(% style="background-color:#4f81bd; color:white; width:102px" %)**Band Width**
43 43  |(% style="width:134px" %)**EU868**|(% style="width:400px" %)14dBm|(% style="width:362px" %)SF=12|(% style="width:102px" %)125Khz
44 44  |(% style="width:134px" %)**US915**|(% style="width:400px" %)20 or 22 dBm (depends on max output of module)|(% style="width:362px" %)SF=10|(% style="width:102px" %)125Khz
45 45  |(% style="width:134px" %)**AS923**|(% style="width:400px" %)14dBm|(% style="width:362px" %)SF=12|(% style="width:102px" %)125Khz
46 46  
47 -
48 -
49 49  == 2.2  Adaptive Data Rate (ADR) and set max distance ==
50 50  
51 51  
52 -**ADR** is the feature that Server will ask End Node to adjust the TXP and DR according to some rules in the server. This is for the purpose of Network Management and Optimize End Node battery life-time.
51 +(% style="color:#037691" %)**ADR**(%%) is the feature that Server will ask End Node to adjust the TXP and DR according to some rules in the server. This is for the purpose of Network Management and Optimize End Node battery life-time.
53 53  
54 54  
55 55  By default, ADR is turn on((% style="color:#037691" %)**AT+ADR=1**) (%%)so End node ADR feature is enable.
... ... @@ -59,46 +59,64 @@
59 59  
60 60  (% style="color:#037691" %)**AT+ADR=0**
61 61  
62 -(% style="color:#037691" %)**AT+DR=0**
61 +(% style="color:#037691" %)**AT+DR=0     **~/~/(%%) Use longest distance modulation
63 63  
64 -(% style="color:#037691" %)**AT+TXP=0**
63 +(% style="color:#037691" %)**AT+TXP=0   **(%%)~/~/ Use max power   For EU868, max power can be is AT+TXP=50
65 65  
66 66  
67 67  This can be downlink via the LoRaWAN downlink command, see [[this link>>url:http://wiki.dragino.com/xwiki/bin/view/Main/End%20Device%20AT%20Commands%20and%20Downlink%20Command/#H8.2UseDownlinkCommandtosetafixuplinkDR]] for reference.
68 68  
69 69  
70 -
71 71  == 2.3  Check for short distance problem ==
72 72  
73 73  
74 74  According to the above technology, if we have a problem on the distance, we can first check if the end node is trying to longest distance modulation already. We can see that from the LoRaWAN server. Below is an example from Chirpstack.
75 75  
76 -
77 77  We can see the traffic in gateway's page and know that the distance is SF12 / BW125. (note, server is not able to know Transmit Power settings from End Node)
78 78  
79 -
80 80  [[image:image-20221006185826-3.png]]
81 81  
82 82  
83 -
84 84  == 2.4  Best software settings for the longest distance ==
85 85  
86 86  
87 87  Below are the settings for longest distance transmission. ( will reduce battery life)
88 88  
89 -* (% style="color:#037691" %)AT+ADR=0     (%%)~/~/  Disable ADR
90 -* (% style="color:#037691" %)AT+DR=  0     (%%)~/~/  Use the smallest DR
91 -* (% style="color:#037691" %)AT+TXP=0    (%%) ~/~/  Use max power.
84 +* (% style="color:#037691" %)**AT+ADR=0**          (%%)~/~/  Disable ADR  (% style="color:#037691" %)**(downlinkpayload: 2200FFFF)**
85 +* (% style="color:#037691" %)**AT+DR=0**           (%%)~/~/  Use the smallest DR,the longest distance modulation (% style="color:#037691" %)**(downlinkpayload: 220000FF)**
86 +* (% style="color:#037691" %)**AT+TXP=0**          (%%)~/~/  Use max power   For EU868, max power can be is AT+TXP=50 (% style="color:#037691" %)** (downlinkpayload: 22000000)**
92 92  
93 93  
94 94  
95 -= 3.  Installation Guidelines =
90 +== 2.5 Debug in Software ==
96 96  
97 -== 3.1  Check the use environment ==
98 98  
93 +Dragino can help client to debug the software for the distance issue. In the case , please send us below info:
99 99  
100 -First , User should notice: Radio link quality and performances are highly dependent of the environment.
95 +* Detail packets include for Join Request, Join Accept, Uplink & Downlink, These packets should include:
96 +** RSSI, DataRate, FCNT, Frequency.
97 +** MIC command detail & Payload detail.
101 101  
99 +
100 += 3.  Analyze at the hardware side =
101 +
102 +== 3.1  Check if the antenna path is good ~-~- For LSN50v2 series end node ==
103 +
104 +
105 +a) Open Enclosure and Check if the antenna connection to module is good.
106 +
107 +b) check if the connector match.
108 +
109 +[[image:image-20221016081725-1.png||height="426" width="706"]]
110 +
111 +
112 += 4.  Installation Guidelines =
113 +
114 +== 4.1  Check the use environment ==
115 +
116 +
117 +First , User should notice: Radio link quality and performances are highly dependent of the environment.Even you have the same hardware and antenna, Different installation will result in different performance.
118 +
102 102  (% style="color:blue" %)**Better performances can be reached with:**
103 103  
104 104  * Outdoor environment.
... ... @@ -106,8 +106,6 @@
106 106  * No high level radio interferes in the ISM band you use.
107 107  * At least 1 meter above the ground.
108 108  
109 -
110 -
111 111  (% style="color:blue" %)**Radio performances are degraded with:**
112 112  
113 113  * Obstacles: buildings, trees...
... ... @@ -117,24 +117,22 @@
117 117  
118 118  
119 119  
120 -== 3.2  Improve the Antenna ==
135 +== 4.2  Improve the Antenna ==
121 121  
122 122  
123 123  In some case, we have to install the device inside the chamber or next to a metal case. So the signal between the antenna and the receiver (gateway) is blocked by the metal. This will greatly reduce the signal. In such case, we can consider using antenna extend cable to extend the antenna to a better position.
124 124  
125 125  
141 += 5.  Some real-world case =
126 126  
127 -= 4.  Some real-world case =
143 +== 5.1  Server reason cause end node has problem on Join. ==
128 128  
129 -== 4.1  Server reason cause end node has problem on Join. ==
130 130  
131 -
132 132  In one case, the customer is using AWS IoT Core and gateway to connect to AWS via Basic Station Connection, Frequency Band is AU915 sub-band 2. For some unknown reason, AWS always set downlink power to 0dBm, which cause the gateway only emit a very low power and lead to a short distance for sensor.
133 133  
134 134  
135 135  Below is the output log in gateway side ( SSH Access to Gateway and Check Station log)
136 136  
137 -
138 138  [[image:image-20221006185826-4.png]]
139 139  
140 140  
... ... @@ -142,4 +142,32 @@
142 142  
143 143  Reference Link:  [[http:~~/~~/wiki.dragino.com/xwiki/bin/view/Main/Change%20Gateway%20Power/#H1.A0Overview>>http://wiki.dragino.com/xwiki/bin/view/Main/Change%20Gateway%20Power/#H1.A0Overview]]
144 144  
158 +
159 +== 5.2 Chirpstack Default settings to 64 channels which cause Signal Poor. ==
160 +
161 +
162 +In this case, User use a Chirpstack LoRaWAN server with default settings. The Frequency Band is US915 and default settings of Chirpstack has all channels ( All sub-bands , total 72 channels) enable. User use a LDS03A and a LPS8N LoRaWAN gateway for the test.
163 +
164 +
165 +There is a strange issue: LDS03 has a very good RSSI ( RSSI=-40) during OTAA Join. But The LDS03A give a very poor RSSI after OTAA Join. After debug, it proves that the issue is with ChirpStack Frequency band settings. The ChirpStack server enables all 72 channels and the LDS03A will also use all channels after OTAA Join, but the LPS8N only can support 8 channels and set to Sub-Band2. When the LDS03A sends an uplink packet in the channel LPS8N doesn't support, because LDS03A is very close to LPS8N, LPS8N pick up this not support frequency and send to server. So in the platform we see a uplink packet with very poor RSSI.
166 +
167 +
168 +Above issue was confirmed and solved after set the ChirpStack support channels to sub-band2. See below for photos during debug.
169 +
170 +[[image:image-20221031233628-2.png]]
171 +
172 +
173 +[[image:image-20221031233759-3.png]]
174 +
175 +
176 +[[image:image-20221101000006-1.png||height="353" width="931"]]
177 +
178 +
179 += 6. Use a repeater =
180 +
181 +
182 +In some cases, user can consider use a repeater for limitation transmition.
183 +
184 +See here for how to set up: [[http:~~/~~/wiki.dragino.com/xwiki/bin/view/Main/User%20Manual%20for%20All%20Gateway%20models/LoRaWAN%20IoT%20Kit%20v3%20User%20Manual/#H7.Example6:LimitedLoRaWANrelay >>http://wiki.dragino.com/xwiki/bin/view/Main/User%20Manual%20for%20All%20Gateway%20models/LoRaWAN%20IoT%20Kit%20v3%20User%20Manual/#H7.Example6:LimitedLoRaWANrelay]]
185 +
145 145  
image-20221016081725-1.png
Author
... ... @@ -1,0 +1,1 @@
1 +XWiki.Edwin
Size
... ... @@ -1,0 +1,1 @@
1 +569.8 KB
Content
image-20221031233524-1.png
Author
... ... @@ -1,0 +1,1 @@
1 +XWiki.Edwin
Size
... ... @@ -1,0 +1,1 @@
1 +75.1 KB
Content
image-20221031233628-2.png
Author
... ... @@ -1,0 +1,1 @@
1 +XWiki.Edwin
Size
... ... @@ -1,0 +1,1 @@
1 +72.3 KB
Content
image-20221031233759-3.png
Author
... ... @@ -1,0 +1,1 @@
1 +XWiki.Edwin
Size
... ... @@ -1,0 +1,1 @@
1 +80.4 KB
Content
image-20221101000006-1.png
Author
... ... @@ -1,0 +1,1 @@
1 +XWiki.Edwin
Size
... ... @@ -1,0 +1,1 @@
1 +88.5 KB
Content