Test Report: RAK7289 WisGate Edge Pro Coverage Range

Objective

The objective of this evaluation is to practically test out the coverage range of the RAK7289 WisGate Edge Pro industrial-grade commercial gateway. To achieve that, we will make the test using three distinct antennas: the 5 dBi Fiberglass Antenna, the 9 dBi Fiberglass Antenna, and the 12 dBi Directional Antenna. We will compare the results and conclude based on real data.

Testing Process

The RAK7289 is mounted on the top of a 100-meter-high building.
Point-to-Point communication is established between the node and the RAK7289.
The RAK3172 node is configured to transmit data using a fixed RF power (20 dBm), bandwidth (125 K), fixed spreading factor (SF12), and frequency point (868.3 MHz for EU868 and 904.7 MHz for US915). The payload size is fixed at 32 bytes. The only variable introduced to the setup is the distance between the RAK3172 node and the RAK7289 gateway.
The RSSI and SNR measurements acquired by the RAK7289 are recorded and compared to analyze the coverage range.

Testing Equipment

Gateway - RAK7289 WisGate Edge Pro
Antennas

Node (end device) – RAK3172 WisDuo Evaluation board and LPWAN Module

Testing Environment

The gateway is positioned on the roof of a tall building (100 meters), where a set of measurements are made with different antennas. The area is urban but with no tall buildings.

Figure 1. Different antennas connected to the gateway

The measurements are made using the same node, with fixed parameters. Only the distance is changed. The line of sight is direct.

Figure 2. Line of sight

Antenna Parameters

5 dBi Fiberglass Antenna (EU868)

5 dBi Fiberglass Antenna (US915)

9 dBi Fiberglass Antenna (EU868)

9 dBi Fiberglass Antenna (US915)

12 dBi Directional Linear Polarized Panel Antenna

Test Results for EU868 (868.3 MHz)

Received packet’s serial number	1	2	3	4	5	6	7	8	9	10	AVG
snr_avg	-11.3	-9.3	-9.5	-9	-11	-9.3	-10	-9.5	-10.5	-10	-9.94
rssi_sig	-103	-101	-101	-101	-102	-101	-101	-101	-102	-102	-101.5

Table 1. 5 dBi Fiberglass Antenna; Test Frequency: 868.3 MHz; Distance: 8.6 km

Received packet's serial number	1	2	3	4	5	6	7	8	9	10	AVG
snr_avg	-10.5	-11	-9.8	-10.8	-9.5	-9.8	-9.5	-10	-8.8	-10	-10
rssi_sig	-99	-99	-98	-99	-98	-97	-99	-99	-98	-99	-98.5

Table 2. 9 dBi Fiberglass Antenna; Test Frequency: 868.3 MHz; Distance: 8.6 km

Received packet's serial number	1	2	3	4	5	6	7	8	9	10
snr_avg	No packets can be received.
rssi_sig	No packets can be received.

Table 3. 5 dBi Fiberglass Antenna; Test Frequency: 868.3 MHz; Distance: 11 km

Received packet's serial number	1	2	3	4	5	6	7	8	9	10
snr_avg	No packets can be received.
rssi_sig	No packets can be received.

Table 4. 9 dBi Fiberglass Antenna; Test Frequency: 868.3 MHz; Distance: 11 km

Received packet's serial number	1	2	3	4	5	6	7	8	9	10
snr_avg	-23.8	-23	-22	-19.3	-21.8	-23.5	-20.8	-23	-24.5	-21.5
rssi_sig	-112	-111	-111	-109	-111	-112	-110	-111	-114	-111

Table 5. 12 dBi Directional Antenna; Test Frequency: 868.3 MHz; Distance: 11 km

Test Results for US915 (904.7 MHz)

Received packet's serial number	1	2	3	4	5	6	7	8	9	10	AVG
snr_avg	2.5	1.5	1	1	2	-2.3	-2.3	-0.5	0.8	2.3	0.6
rssi_sig	-103	-102	-104	-104	-103	-104	-104	-104	-104	-102	-103.4

Table 6. 5 dBi Fiberglass Antenna; Test Frequency: 904.7 MHz; Distance: 8.6 km

Received packet's serial number	1	2	3	4	5	6	7	8	9	10	AVG
snr_avg	1.5	1	0.5	0.3	1.3	1.5	2.3	2.3	2.5	2	1.52
rssi_sig	-101	-101	-101	-102	-101	-100	-101	-101	-100	-101	-100.9

Table 7. 9 dBi Fiberglass Antenna; Test Frequency: 904.7 MHz; Distance: 8.6 km

Received packet's serial number	1	2	3	4	5	6	7	8	9	10	AVG
snr_avg	-12.3	-13.5	-11.3	-11.3	-10.3	-11	-11.3	-10.3	-10	-9.5	-11.1
rssi_sig	-120	-120	-118	-118	-117	-117	-118	-118	-118	-116	-118

Table 8. 5 dBi Fiberglass Antenna; Test Frequency: 904.7 MHz; Distance: 11 km

Received packet's serial number	1	2	3	4	5	6	7	8	9	10	AVG
snr_avg	-9.5	-7.3	-7.3	-8.3	-6.3	-7.8	-6.5	-6.8	-6.8	-8	-7.46
rssi_sig	-114	-113	-113	-113	-112	-113	-111	-112	-112	-113	-112.6

Table 9. 9 dBi Fiberglass Antenna; Test Frequency: 904.7 MHz; Distance: 11 km

Received packet's serial number	1	2	3	4	5	6	7	8	9	10	AVG
snr_avg	-6	-4.5	-5.3	-6.8	-5.5	-6.5	-5	-6	-7	-7	-5.96
rssi_sig	-114	-113	-113	-113	-113	-113	-114	-113	-113	-113	-113.2

Table 10. 12 dBi Directional Antenna; Test Frequency: 904.7 MHz; Distance: 11 km

Conclusion

The coverage range of the RAK7289-EU868 has been measured to be approximately 8.6 km, regardless of whether a 5 dBi or a 9 dBi fiberglass antenna is used. The RAK7289-EU868 can only receive a limited number of packets at a position of 11 km although a 12 dBi directional antenna is used.

In contrast, the coverage range of the RAK7289-US915 exceeds 11 km. Even when using a 5 dBi fiberglass antenna, the RAK7289-US915 can still receive packets normally at a distance of 11 km.

The difference in performance between the RAK7289-EU868 and RAK7289-US915 can be attributed to the antenna used by the RAK3172 node, which is less effective for the EU868 band. Therefore, it is important to carefully consider antenna selection for optimal performance.

Regarding coverage range, the 9 dBi fiberglass antenna outperforms the 5 dBi fiberglass antenna, and the 12 dBi directional antenna outperforms the 9 dBi fiberglass antenna. However, it is important to note that higher antenna gain results in greater directivity, more concentrated energy, and a narrower lobe.

If a higher antenna gain is used (which means a narrower lobe), the tilt angle of the antenna must be considered, particularly when the antenna is installed at a high elevation. To ensure proper coverage of the target area, the antenna should be tilted towards the ground at an appropriate angle, which depends on the antenna setup height and the distance from the target area.