100公里TDD雙向視訊資料無線傳輸

100km TDD bidirectional video data wireless transmission Appearance

Version history

日期	版本	Modification description
20231219	V1.0	Initial version
20240315	V2.0	Modify the weight dimensions, modify the total data  in Table MCS & 靈敏度
20240405	V3.0	Add multiple sets of coexistence switches. Modify the serial-to-network configuration mode. Modify the ID number length and modify the English words of background noise detection. Added the frequency matching function

Overview

Vcan1933-8-Watt PA is a self-developed TDD bidirectional graph integrated wireless transmission device. The product has the functions of real-time interference detection, 自適應頻率選擇, adaptive stream, automatic retransmission, and automatic power control, which greatly improves the ability of anti-multipath and anti-interference, and has the characteristics of high reliability, 穩定性好, 和低延遲.

This product is suitable for firefighting, 檢查, 監控, 以及其他場景,  and can transmit 100KM under good air-to-ground vision. 

Product Characteristics

• Support long-distance transmission: 4M code flow can be transmitted up to 100km.
• Supports large bandwidth transmission: Up to 17Mbps@10MHz.
• Supports automatic repeater transmission: Supports automatic trunk addition.
• Supports multi-interface design: The device has two network ports and four serial ports, supporting RS232/TTL/RS422/SBUS.
• Supports automatic frequency selection: Automatic detection of interference signals, real time selection of the optimal frequency point.
• Supports automatic retransmission: Automatic retransmission of burst error data improves data reliability.
• Supports adaptive stream: The channel modulation mode is automatically adjusted according to the signal quality in real time.
• Supports automatic power control: Close range automatic adjustment of transmission power, reduce power consumption.
• 支援自動天線選擇: 根據遮擋情況, the optimal antenna transmission is selected in real time.
• Supports the coexistence of multiple set: 支援鋼彈 6 sets of equipment at the same time fixed frequency use.
• Supports the frequency matching function: Software can be used to configure the frequency and hardware key frequency.

規範

系統參數	技術指標
Equipment model	Vcan1933-8W
工作頻率	1350～1470MHz
射頻	2T2R
發射功率	39分貝 (8-功率放大器)
傳輸距離	100知識管理 (空對地視距)
頻道頻寬	10兆赫
調製方式	QPSK/16QAM
接收靈敏度	See Table (MCS & 靈敏度)
Speed	17Mbps@16QAM3/4
通訊加密	AES256
傳輸延遲	≤10ms
射頻介面	SMA*2
Equipment interface	XT30PW-M
Equipment interface	100Mbps Ethernet*2
	TTL/RS232*2
	RS422*1
	SBUS/TTL*1
整體功耗	≤48W@4Mbps(Air uint)
	≤12W@1Mbps(Ground uint)
尺寸(長*寬*高)	163*77*25毫米
重量	340G
工作電壓	DC22~30V,典型值: +24V@2A
Working temperature	-40~+75℃

MCS & 靈敏度 (10兆赫)
No.	MCS	Total uplink and downlink  throughput (Mbps的)	靈敏度 (分貝)
1	QPSK1/3	4.0	-99
2	QPSK1/2	5.8	-98
3	QPSK2/3	7.1	-97
4	QPSK3/4	8.2	-96
5	16QAM1/3	8.0	-96
6	16QAM1/2	11.6	-95
7	16QAM2/3	14.3	-93
8	16QAM3/4	16.4	-91

Product dimension and weight

尺寸圖

Dimension and weight

• 尺寸 (長*寬*高): 163mm*77mm*25mm(包括 SMA 10mm)
• 重量 : 340G

產品介面定義

Interface diagram

The interface of the Vcan1933-8W device includes the XT30PW-M power interface and J30J-25pin data interface. The interface has RS232/TTL*2, RS422*1, SBUS/TTL*1 and 100 Mbit/s Ethernet*2.

介面定義

電源介面: XT30PW-M. 電源範圍: DC22-30V Typical value:24V@2A 

Linear  order.	引腳名稱	介面定義	Interface description	Signal  direction
1,2,3,4	接地	地面	地面
5	422一個	Serial port 3 RS-422	Receiving data RX+	一世
6	422乙		Receiving data RX-	一世
7	422Z		Transmitting data TX-	氧
8	422是		Transmitting data TX+	氧
9	TXD_A	Serial port 1 RS232/TTL	Transmitting data TX	氧
10	RXD_A		Receiving data RX	一世
11	TXD_B	Serial port 2 RS232/TTL	Transmitting data TX	氧
12	RXD_B		Receiving data RX	一世
13	接地		序列埠 2 地面	氧
14	SBUS /TTL TX	Serial port 4 SBUS/TTL	SBUS/TTL sending	氧
15	SBUS /TTL RX		SBUS/TTL receiving	一世
16	SBUS/TTL GND		SBUS/TTL ground	氧
17	TX1P+	網路連接埠 1	Transmitting data TX+	氧
18	TX1M-		Transmitting data TX-	氧
19	RX1P+		Receiving data RX+	一世
20	RX1M-		Receiving data RX-	一世
21	接地	地面	序列埠 1 地面	氧
22	TX2P+	網路連接埠 2	Transmitting data TX+	氧
23	TX2M-		Transmitting data TX-	氧
24	RX2P+		Receiving data RX+	一世
25	RX2M-		Receiving data RX-	一世

• 注意 1: Signal direction I indicates radio input and direction O indicates radio output.
• 注意 2: When using the serial port 1/2 of the device, please check whether it is TTL level or RS232 level.

一世ndicator Meaning

The RSSI light represents the strength of the received signal
Number of RSSI energy lights on	接收能量 dBm
3 RSSI lights on	about -50dBm
2 RSSI lights on	about -80dBm
1 RSSI light on	about -95dBm

Module type	模式	Vcan1933-8W light status
		壓水堆	SYNC	區域網路 1 LAN 2	接收訊號強度指數 123
掌握	Un-sync	Powered on	Flashing	Data sending and  receiving, 閃爍	離開
掌握	Sync	Powered on	Steady on	Data sending and  receiving, 閃爍	Proportional to the  strength of the received  signal
奴隸	Un-sync	Powered on	Flashing	Data sending and  receiving, 閃爍	Searching
奴隸	Sync	Powered on	Steady on	Data sending and  receiving, 閃爍	Proportional to the  strength of the received  signal

When the master and slave devices are not synchronized, the PWR indicator of the  master and slave devices is steady on, the SYNC indicator is blinking, and the RSSI  indicator of the master device is off. The RSSI of the slave device will always be in the  search state. After the master/slave synchronization, the SYNC indicator of the  master/slave is steady on. The master-slave RSSI lamp displays the received signal  energy intensity. When the network port is sending or receiving data, the master and  slave devices correspond to LAN1, and the LAN2 indicator blinks.

More information about the product

時分雙工 (Time Division Duplexing) is a communication technique used in wireless systems where the uplink (transmitting data from the ground control station to the drone) 和下行鏈路 (transmitting video and data from the UAV to the ground receiver or GCS) share the same frequency channel but operate in different time slots. This allows bidirectional communication without requiring separate frequency bands for each direction.

TDD Protocol Optimization

• Ensure proper time slot allocation between uplink (sending data) 和下行鏈路 (receiving data) for efficient bidirectional communication.
• Adaptive TDD allows dynamic allocation based on data traffic needs.
• Useful in applications where uplink and downlink traffic are asymmetric (例如, video streaming).

Comparison Between TDD and FDD

特徵	時分雙工	頻分雙工
Spectrum Usage	Single frequency band	Separate bands for uplink and downlink
Traffic Adaptability	Highly adaptable to asymmetric traffic	Fixed uplink/downlink ratio
Equipment Complexity	Lower cost and simpler hardware	Requires duplexers, increasing cost
Channel Reciprocity	是, supports advanced techniques like beamforming	沒有
干涉	Requires strict synchronization	Less prone to interference

TDD is widely used in modern communication systems, including those requiring long-range bidirectional video transmission due to its efficiency and flexibility.

Power and Size Constraints:

• Lightweight hardware to minimize the impact on drone flight performance.
• Low-power consumption design to maximize drone battery life.
• Compact form factor to fit within the drone’s payload.

天線系統:

• On Drone: Fiberglass omnidirectional or small directional patch antennas.
• 地面站: High-gain parabolic, Yagi antennas or flat panel antennas with tracking systems for long-range communication.

應用

1. Surveillance and Security: Real-time video streaming from drones for law enforcement or border control.
2. 廣播: High-definition aerial footage for live events or media.
3. Agriculture: Monitoring crops and livestock over vast areas.
4. 災難應變: Sending live video from disaster sites for better coordination.

The 傳輸範圍 of an 8-watt power amplifier (PA) depends on a variety of factors, 包含:

1. 頻帶: Higher frequencies experience more signal loss over distance (higher free-space path loss).
2. 天線增益: The type and gain of the antenna at both ends (發射器和接收器) significantly impact the range.
3. 環境條件: Factors like terrain, 建築物, weather (雨, 多霧路段), 和視線 (LoS) can affect range.
4. Modulation Scheme and Data Rate: More complex modulation schemes (例如, QAM) and higher data rates may reduce effective range due to higher sensitivity to signal degradation.
5. 接收靈敏度: The ability of the receiver to detect a weak signal at a specific distance.