100km TDD bidirectional video data wireless transmission

100km TDD bidirectional video data wireless transmission Appearance

Version history

Tarih	Sürüm	Modification description
20231219	V1.0	Initial version
20240315	V2.0	Modify the weight dimensions, modify the total data  in Table MCS & Hassasiyet
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, adaptive frequency selection, 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, iyi stabilite, ve düşük gecikme.

This product is suitable for firefighting, denetleme, izleme, ve diğer senaryolar,  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.
• Otomatik anten seçimini destekler: Tıkanma durumuna göre, the optimal antenna transmission is selected in real time.
• Supports the coexistence of multiple set: Support up to 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.

şartname

System parameter	Technical index
Equipment model	Vcan1933-8W
Çalışma frekansı	1350~1470MHz
Radyo frekansı	2T2R
İletim gücü	39dBm (8-watt PA)
Transmission distance	100km (Air-to-ground LOS)
Kanal bant genişliği	10MHz
Modülasyon modu	QPSK/16QAM
Alma hassasiyeti	See Table (MCS & Hassasiyet)
Hız	17Mbps@16QAM3/4
Communication encryption	AES256
İletim gecikmesi	≤10ms
Radio frequency interface	SMA*2
Equipment interface	XT30PW-M
Equipment interface	100Mbps Ethernet*2
	TTL/RS232*2
	RS422*1
	SBUS/TTL*1
Overall power consumption	≤48W@4Mbps(Air uint)
	≤12W@1Mbps(Ground uint)
Boyut(U*G*Y)	163*77*25mm
Ağırlık	340g
Working voltage	DC22~30V,Tipik değer: +24V@2A
Çalışma sıcaklığı	-40~+75℃

MCS & Hassasiyet (10MHz)
No.	MCS	Total uplink and downlink  throughput (Mb/sn)	Hassasiyet (dBm)
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

Dimension diagram

Dimension and weight

• Boyut (U*G*Y): 163mm*77mm*25mm(including SMA 10mm)
• Ağırlık : 340g

Product interface definition

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.

Arayüz tanımı

Güç arayüzü: XT30PW-M. Güç kaynağı aralığı: DC22-30V Typical value:24V@2A 

Linear  order.	Pin adı	Arayüz tanımı	Arayüz açıklaması	Signal  direction
1,2,3,4	GND	Zemin	Zemin
5	422bir	Serial port 3 RS-422	Receiving data RX+	BEN
6	422B		Receiving data RX-	BEN
7	422Z		Transmitting data TX-	O
8	422e		Transmitting data TX+	O
9	TXD_A	Serial port 1 RS232/TTL	Transmitting data TX	O
10	RXD_A		Receiving data RX	BEN
11	TXD_B	Serial port 2 RS232/TTL	Transmitting data TX	O
12	RXD_B		Receiving data RX	BEN
13	GND		Seri bağlantı noktası 2 ground	O
14	SBUS /TTL TX	Serial port 4 SBUS/TTL	SBUS/TTL sending	O
15	SBUS /TTL RX		SBUS/TTL receiving	BEN
16	SBUS/TTL GND		SBUS/TTL ground	O
17	TX1P+	Ağ bağlantı noktası 1	Transmitting data TX+	O
18	TX1M-		Transmitting data TX-	O
19	RX1P+		Receiving data RX+	BEN
20	RX1M-		Receiving data RX-	BEN
21	GND	Zemin	Seri bağlantı noktası 1 ground	O
22	TX2P+	Ağ bağlantı noktası 2	Transmitting data TX+	O
23	TX2M-		Transmitting data TX-	O
24	RX2P+		Receiving data RX+	BEN
25	RX2M-		Receiving data RX-	BEN

• Not 1: Signal direction I indicates radio input and direction O indicates radio output.
• Not 2: When using the serial port 1/2 of the device, please check whether it is TTL level or RS232 level.

BENndicator Meaning

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

Modül türü	Mod	Vcan1933-8W light status
		Güç	SYNC	LAN 1 LAN 2	RSSI 123
usta	Un-sync	Açık	Flashing	Data sending and  receiving, yanıp sönüyor	Kapalı
usta	Sync	Açık	Steady on	Data sending and  receiving, yanıp sönüyor	Proportional to the  strength of the received  signal
köle	Un-sync	Açık	Flashing	Data sending and  receiving, yanıp sönüyor	Arama
köle	Sync	Açık	Steady on	Data sending and  receiving, yanıp sönüyor	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

TDD (Zaman Bölmeli Çift Yönlendirme) is a communication technique used in wireless systems where the uplink (transmitting data from the ground control station to the drone) ve aşağı bağlantı (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) ve aşağı bağlantı (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 (örneğin, video akışı).

Comparison Between TDD and FDD

Özellik	TDD	FDD
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	Evet, supports advanced techniques like beamforming	Yok hayır
Interference	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.

Antenna System:

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

Uygulamalar

1. Gözetim ve Güvenlik: Real-time video streaming from drones for law enforcement or border control.
2. Yayıncılık: High-definition aerial footage for live events or media.
3. Tarım: Monitoring crops and livestock over vast areas.
4. Afet Müdahalesi: Sending live video from disaster sites for better coordination.

The transmission range of an 8-watt power amplifier (PA) depends on a variety of factors, içermek:

1. Frekans Bandı: Higher frequencies experience more signal loss over distance (higher free-space path loss).
2. Anten Kazanımı: The type and gain of the antenna at both ends (verici ve alıcı) significantly impact the range.
3. Çevre Koşulları: Factors like terrain, binalar, hava durumu (yağmur, sis), ve görüş hattı (LoS) can affect range.
4. Modulation Scheme and Data Rate: More complex modulation schemes (örneğin, QAM) and higher data rates may reduce effective range due to higher sensitivity to signal degradation.
5. Alıcı Hassasiyeti: The ability of the receiver to detect a weak signal at a specific distance.