Date: September 3, 2025, Sunny Day

Equipment: HCL536 -2W Video Data Transmitter Receiver with two-way data link, 2W transmission power, 30km range, 1.4GHz frequency band, 20MHz bandwidth, automatic frequency hopping. The broadband data transmitter end is the access node; the broadband data receiver end is the central node. The time slot ratio of the wireless link:

Link from access node to central node: Link from central node to access node = 4:1

The test IP Camera is set to 1080P25 with a maximum bitrate of 3.8Mbps.

Locations:

The transmitter end is at Daxing Mountain in Shuangyuan Bay, Huizhou, with an altitude ranging from 150 to 180 meters, the receiver end is at the seaside of Dapeng Peninsula in Shenzhen, at an altitude of 40 to 50 meters, about 31 km apart. There are no large obstructions between the two locations. The transmitter end is to the northeast of the receiver end.

The transmitter end is a popular tourist area. During the test, there were many tourists nearby. The front end of the transmitter antenna was partially covered by some plants. The following pictures show the transmitter end.

The receiver end is located at the foot of a mountain by the seaside, with an altitude of around 40 to 50 meters. Within a 100-meter radius, there are a few tourists, seaside hotels and vacation villas, as well as base station antenna tower.

Test data:

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1. The transmitter end uses small sucker antennas, while the receiver end uses 120cm fiberglass antennas. The test results for transmitting 15 Mbps data:

Test result: when transmitting 15 Mbps data from the transmitter to the receiver, the bit error rate is 0%.

Data reported over the wireless link at the transmitter end:

The SNR value is around +13 to +15, and the self-measurement distance of the wireless link is 31,060 meters.

Data reported on the wireless link at the receiver end:

The SNR values at the receiver end are +11 and +4, and the range report indicates a distance of 31070 meters.

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2. The transmitter end is replaced with rubber tube antennas, and the receiver end is changed to small sucker antennas. The test results for transmitting 10 Mbps data:

The test results show that the data transmission rate from the transmitter end to the receiver end is approximately 6 Mbps.

The transmitter end reported the data:

The SNR value at the transmitter end is +6 and +11, the reported distance is 31,050 meters.

Data reported on the wireless link at the receiver end:

The SNR values at the receiver end are +2 and 0.

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3. Both the transmitter end and the receiver end are replaced with rubber tube antennas; the test is conducted to transmit 10 Mbps data:

The test results show that the data transmission rate from the transmitter end to the receiver end is approximately 4 to 6 Mbps.

Data reported over the wireless link at the transmitter end:

SNR values are +4 and +5.

Data reported on the wireless link at the receiver end:

SNR values at receiver end are +2 and -4.

When both ends are equipped with rubber tube antenna, the transmitter end is connected with an IP Camera (1080P25, with a maximum bitrate of 3.8 Mbps). The video transmission is tested and found to be smooth.