低成本無人機無線電數據鏈

1. 介紹

The digital data link modules are used for the communication between UAVs and the ground station (GS) to send data and receive commands. The two-way radio link must have high reliability and always be connected during the flight. Link module on UAV side must have a low price due to limitation on UAV total cost in mass production.

The main feature of this data link is the low rate of sending and receiving data to reduce the occupied bandwidth and subsequently increase the sensitivity of modules.

筆記 1: The GS module must be capable of communicating with 12 UAVs simultaneously.

2. 技術規格

參數	價值
Maximum Operating Range	25千米
Operating Height	10-5000米
Max UAVs Speed	100多發性硬化症
頻帶	超高頻 (upper 400MHz)
Frequency Channel Selection	是
Frequency hopping	選修的 (is preferred)
UAV module Transmit Power	2W¯¯
GS module Transmit Power	10W¯¯
數據速率	See the below figures (software selectable in range of 1kbps to 500kbps)
Packet transmission delay	≤ 5 毫秒
錯誤偵測	CRC
Channel Coding (FEC)	是
加密	是
Senstivity	−122分貝@20千比特/秒 −199分貝@40千比特/秒 −111分貝@230千比特/秒 −108分貝@500千比特/秒
MIMO Antenna	選修的
Operation mode	點對點 (GS to one UAV) Point to MultiPoint (GS to maximum 12 UAVs on air, 同時地)
Receive satuation power	10分貝
No damage receiver power	20分貝
Boot time	Less than 2sec
Operationg time	最大限度 30 minutes continuously
Working tempearure	−20°𝐶 ~ + 60°𝐶

Three working modes for this digital data link can be considered, which are described in the following figures. According to the complexity and the cost of link module (specially on UAV side), each topology can be selected.

3. 群組網類型

1- The working frequency of all uplinks and downlinks are different (the nodes work in different channels).

2- The frequency of uplink and downlink for each node is the same but is different with other nodes.

3- The working frequency of all nodes is same as other nodes and GS is managing the nodes to avoid data loss and interference.

筆記 2: In all the above three topologies, frequency hopping is a great advantage but is not a critical feature.

4. Electrical and Interface

參數	價值
UAV Installed Module
輸入電壓	9～18V
序列埠	1, RS422
串口波特率	9600~460800bps,
Antenna Connector	SMA
Interface Connector	J30J or DB type
重量	Less than 150g
尺寸 (LxWxH)	8 × 8 × 3 公分
GS Installed Module
輸入電壓	9～18V
Serail Port	1, RS422
Serial Buad Rate	9600~460800bps,
以太網絡	RJ-45, 100Mbps的
Antenna Connector	N-Type
Interface Connector	J30J or DB type
重量	Less than 500g
尺寸 (LxWxH)	15 × 10 × 4 公分