This document outlines the system requirements for a communication system between a mini air vehicle (MAV) and ground station. It will allow for downlinking of HD video and telemetry data from the MAV to the ground station as well as command and control from the ground station to the MAV. The system consists of an airborne transceiver unit and ground transceiver unit. Key requirements include supporting HD video transmission up to 10 km, operating from -20°C to 70°C altitudes up to 20,000 feet, and encrypting data during transmission.

1. System Requirement Specification
for Mini Air Vehicle

2. Introduction:
This document describes the System Requirements
Specifications (SRS) of a communication system for Mini-Air-Vehicle
(MAV). The communication system under consideration consists of a
pair of transceiver units namely: airborne unit and ground unit. These
two units will be used together to accomplish the following:
•Down-streaming of HD video data from MAV to ground station
•Down-streaming of telemetry data from MAV to ground station
•Command and control data communication from ground station to
MAV.

3. System Context
• This project aims at developing a RF communication system which can
be used in an MAV application for video recording and down streaming
purposes.
•The RF communication system consists of a transceiver pair one on the
MAV (referred as airborne unit) and one on the ground (referred as
ground unit).
• The airborne unit is responsible for collecting the compressed video
from the on board camera unit and telemetry data from autopilot of the
MAV.
•The ground unit is responsible for demodulating and decoding the
video and telemetry downstream data and present it to the Ground
Control Station (GCS).

4. The context in which the communication system shall be used.

5. System Overview:
The system input/output block diagram of the airborne and ground
units. The airborne unit shall interface with the camera unit using dual
Ethernet interface, one for the regular colour camera. The airborne unit
shall have other interfaces like SPI, UART, I2C for interfacing with
autopilot system of the MAV. The airborne unit shall operate using a DC
power source ranging between 8-18 V.
The ground unit shall have one Ethernet interface for transferring the
decoded video and telemetry data to the GCS. The ground unit shall also
have additional interfaces like SPI, UART, USB and I2C for interfacing the
GCS system. The ground unit shall operate using a DC power source
ranging between 8-18 V.

6. System input/output block diagram of airborne and ground
communication systems.

7. Sl.
No
Interface I/
O
Airborne
unit
Ground
unit
Remarks
1 Ethernet I/O 2 ports 1 port 2 Ethernet ports (one for
regular color camera and
another for IR camera)
2 UART I/O 3 ports 3 ports each containing dedicated Tx,
Rx and Gnd. Signal level shall
be at LVTTL (0-3.3 V)
3 SPI I/O 1 port 1 port Signal level shall be at LVTTL
(0-3.3 V)
4 I2C I/O 1 port 1 port Signal level shall be at LVTTL
(0-3.3 V)
5 Power I 2 port 2 port 8-18 V DC, 12 W max
6 RF port I/O 1 port 1 port S-band
Uplink band: 2.3-2.4 GHz
Downlink band: 2.4-2.5 GHz

8. System requirements specifications
This section describes in detail in the system
requirement specifications of both airborne and
ground communication systems. The requirements are
grouped under following categories:
• Mechanical specifications
• Environmental specifications
• Electrical specifications
• Communication system specifications
• Security specifications
• Interface specifications
The following subsections will detail each of the above
categories in detail

9. SRS ID Parameter Specification
SRS-1 Airborne
Communication
System Dimension
<100 x 55 x 55 mm
SRS-2 Ground
Communication
System Dimension
<100 x 55 x 55 mm
SRS-3 Weight of Airborne
Communication System
< 300 g
SRS-4 Weight of Ground
Communication System
< 400 g
Mechanical specification-
Mechanical specifications of airborne and ground communication systems

10. SRS ID Parameter Specification
SRS-5 Operational
Temperature
Range
-20 °C to + 70 °C
SRS-6 Operational Altitude MSL to 20000 ft.
Environmental Specification-
Environmental specifications of airborne and ground
communication systems

11. SRS ID Parameter Specification
SRS-7 Input Voltage (Battery
Power Supply for both
Airborne and Ground
System)
8V-18V
SRS-8 Electrical Power <12 Watt
Electrical specifications -
Electrical specifications of airborne and ground
communication systems

12. SRS ID Parameter Specification
SRS-9 Communication Range (RF
Line of Sight) for Data,
Control and Video
>/=10 km (Kilo Meter) Aerial
distance
SRS-10 Up link (Non-
Programmable) and
Downlink (Non-
Programmable) Frequency
S-band
SRS-11 Output Impedance 50 Ohm Matched with
Antenna Port with SMA
connector
SRS-12 Bandwidth 10 MHz
The Measure of
performance is for clear Full
HD transmission (1980 x
1080) which is 1080P
SRS-13 Modulation QPSK
SRS-14 Data Rate < /=10 Mbps (Mega Bits Per
Second)
SRS-15 Video Telemetry Support HD 1080p (1980x1080)
SRS-16 Accepted latency delay for the
video
</= 2 second
Communication System specification-

13. SRS-17 On-board Video Recording HD 1080p for 120 minutes
SRS-18 Stored video access from
airborne system
Accessing the store video shall
be through Ethernet with
necessary interlocks for
identification of normal
operation and the video
retrieval functions.
SRS-19 User control provision for
Video Recording Enable and
Disable
Software Provision (Confirm)
SRS-20 Update Rate for telemetry
Data Log
2-50 Hz for Telemetry Data
downlink
1-50 Hz for Command and
Control

14. SRS ID Parameter Specification
SRS-21 Encryption Type 128 bit Encryption
SRS-22 Encryption Control
Option
Software
Security Specifications-
Security specifications of airborne and ground communication
systems

15. SRS ID Parameter Specification
SRS-23 I2C One I2C Port each for Airborne and
Ground Unit
SRS-24 UART One UART Port each for Airborne and
Ground Unit
SRS-25 SPI One SPI Port each for Airborne and
Ground Unit
SRS-26 Serial Interface a) Two additional UART ports for airborne
and ground unit
c) Two USB port for ground unit only
SRS-27 Ethernet Two Ethernet Ports for Airborne and One
for Ground Unit
( Airborne Ethernet shall interface with
Video Processing System/ Camera which
will provide video for transmission.
Ground Ethernet shall interfaced with
Computer/Laptop which will provide
received video for display in Ground
Control Station)
Interface specifications-

16. SRS-28 SMA SMA connector as per
Antenna Used (Two
Antenna or One)
SRS-29 Application Interface for
Ground Communication
System to GCS
For Ground
Communication System to
GCS
Interface specifications of airborne and ground
communication systems