100km TDD bidirektionale Videodaten-Funkübertragung

100km TDD bidirectional video data wireless transmission Appearance

Versionsgeschichte

Datum	Version	Änderungsbeschreibung
20231219	V1.0	Erste Version
20240315	V2.0	Modify the weight dimensions, modify the total data  in Table MCS & Empfindlichkeit
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

Überblick

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 Frequenzauswahl, adaptiver Stream, automatic retransmission, and automatic power control, Dies verbessert die Fähigkeit von Anti-Multipath und Anti-Interferenz erheblich, und zeichnet sich durch hohe Zuverlässigkeit aus, gute Stabilität, und geringe Verzögerung.

Dieses Produkt ist zur Brandbekämpfung geeignet, Inspektion, Überwachung, und andere Szenarien,  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.
• Unterstützt die automatische Antennenauswahl: Je nach Okklusionssituation, 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.

Spezifikation

Systemparameter	Technischer Index
Equipment model	Vcan1933-8W
Arbeitsfrequenz	1350~1470 MHz
Radiofrequenz	2T2R
Sendeleistung	39dBm (8-Watt PA)
Übertragungsentfernung	100KM (Air-to-ground LOS)
Kanalbandbreite	10MHz
Modulationsmodus	QPSK/16QAM
Empfangssensibilität	Siehe Tabelle (MCS & Empfindlichkeit)
Geschwindigkeit	17Mbit/s bei 16QAM3/4
Kommunikationsverschlüsselung	AES256
Übertragungsverzögerung	≤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)
Dimension(L*B*H)	163*77*25Millimeter
Gewicht	340G
Arbeitsspannung	DC22~30V,Typischer Wert: +24V@2A
Arbeitstemperatur	-40~+75℃

MCS & Empfindlichkeit (10MHz)
No.	MCS	Total uplink and downlink  throughput (Mbps)	Empfindlichkeit (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

Abmessungen und Gewicht

• Dimension (L*B*H): 163mm*77mm*25mm(including SMA 10mm)
• Gewicht : 340G

Product interface definition

Schnittstellendiagramm

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.

Schnittstellendefinition

Stromschnittstelle: XT30PW-M. Stromversorgungsbereich: DC22-30V Typical value:24V@2A 

Linear  order.	Pin-Name	Schnittstellendefinition	Schnittstellenbeschreibung	Signal  direction
1,2,3,4	GND	Boden	Boden
5	422EIN	Serial port 3 RS-422	Receiving data RX+	ICH
6	422B		Receiving data RX-	ICH
7	422Z		Transmitting data TX-	O
8	422Y		Transmitting data TX+	O
9	TXD_A	Serial port 1 RS232/TTL	Transmitting data TX	O
10	RXD_A		Receiving data RX	ICH
11	TXD_B	Serial port 2 RS232/TTL	Transmitting data TX	O
12	RXD_B		Receiving data RX	ICH
13	GND		Serieller Anschluss 2 Boden	O
14	SBUS /TTL TX	Serial port 4 SBUS/TTL	SBUS/TTL sending	O
15	SBUS /TTL RX		SBUS/TTL receiving	ICH
16	SBUS/TTL GND		SBUS/TTL ground	O
17	TX1P+	Netzwerkport 1	Transmitting data TX+	O
18	TX1M-		Transmitting data TX-	O
19	RX1P+		Receiving data RX+	ICH
20	RX1M-		Receiving data RX-	ICH
21	GND	Boden	Serieller Anschluss 1 Boden	O
22	TX2P+	Netzwerkport 2	Transmitting data TX+	O
23	TX2M-		Transmitting data TX-	O
24	RX2P+		Receiving data RX+	ICH
25	RX2M-		Receiving data RX-	ICH

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

ICHndicator 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

Modultyp	Modus	Vcan1933-8W light status
		PWR	SYNC	LAN 1 LAN 2	RSSI 123
Master	Un-sync	Powered on	Flashing	Data sending and  receiving, blinkt	Aus
Master	Sync	Powered on	Steady on	Data sending and  receiving, blinkt	Proportional to the  strength of the received  signal
Sklave	Un-sync	Powered on	Flashing	Data sending and  receiving, blinkt	Searching
Sklave	Sync	Powered on	Steady on	Data sending and  receiving, blinkt	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. Wenn der Netzwerkport Daten sendet oder empfängt, the master and  slave devices correspond to LAN1, and the LAN2 indicator blinks.

More information about the product

TDD (Time Division Duplexing) is a communication technique used in wireless systems where the uplink (transmitting data from the ground control station to the drone) und Downlink (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) und Downlink (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 (z.B., Video-Streaming).

Comparison Between TDD and FDD

Besonderheit	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	Ja, supports advanced techniques like beamforming	Nein
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.

Antennensystem:

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

Anwendungen

1. Überwachung und Sicherheit: Real-time video streaming from drones for law enforcement or border control.
2. Rundfunk: High-definition aerial footage for live events or media.
3. Landwirtschaft: Monitoring crops and livestock over vast areas.
4. Katastrophenhilfe: Sending live video from disaster sites for better coordination.

Das Übertragungsreichweite of an 8-watt power amplifier (PA) depends on a variety of factors, einschließlich:

1. Frequenzband: Higher frequencies experience more signal loss over distance (higher free-space path loss).
2. Antenna Gain: The type and gain of the antenna at both ends (Sender und Empfänger) significantly impact the range.
3. Umgebungsbedingungen: Factors like terrain, Gebäude, weather (rain, Nebel), und Sichtlinie (LoS) can affect range.
4. Modulation Scheme and Data Rate: More complex modulation schemes (z.B., QAM) and higher data rates may reduce effective range due to higher sensitivity to signal degradation.
5. Empfängerempfindlichkeit: The ability of the receiver to detect a weak signal at a specific distance.