L/S/C-bands Ground Antenna System

Abstract
Based on the S-band, LETSCOM Develope for L/S/C three band on one antenna system. High-speed data transmission communication for Cubesat and smallsat in Low-Earth-Orbit. Under the condition of frequency and data transmission reliability, the S-band is an ideal band for achieving high-speed data. As long as its operation will be proven in the mission, the antenna and communication system will allow for the reception of high speed data, making it possible for future satellites to transmit images mission to the ground station.

1. Space communication system architecture
The main task is to provide communication for the Cubesat , and the SDR payload transceiver is integrated with the S-band antenna design. Cubesat and ground stations can communicate via links that operate in certain S-band portions.
The ground station has a modular architecture to meet the different communication requirements associated with the application.
The band can support for L, S and C Band up 11GHz in one Antenna system.
The main subsystems of the station are:
- S-Band Azimuth and Elevation mesh antenna;
- S-Band Feed driver
- IF converter
- S-Band Linear Amplifier (optional)
- Satellite tracking System
- Power supply for antenna remote system
- 19” rack mount standard
- The cables installation

2、 S-Band Azimuth and Elevation parabolic mesh antenna;
IRIS-A S-Band Ground Antenna Remote System V2.0

Antenna Diameter	3	Meter
Antenna Effieciency	70	%
Rx Frequency	2.4	GHz
Wavelength	125	mm
3dB Beam width	2.85339811	Deg.
Beam width between first nulls	5.83333333	Deg.
Antenna Gain	35.9982026	dB

The antenna system provides both RHCP or LHCP polarization In best case, the two antennas are perfectly aligned (co-polarized), there will be no loss of polarization between them. However, the satellite has attitude control at a certain angle to beam the ground, it may be in an unclear tumbling state, so the ground needs to be designed to receive as far as possible.

3、 Link Budget
• 3-1 Distance 600km, Data Rate: 500Kbps


3-2 Distance 1200km, Data Rate: 500Kbps


3-3 Distance 2200Km, Data Rate: 500Kbps
Orbital parameters may be subject to minor changes and the exact value is known after successful launch of the IRIS-A The system not include the data handling process and lighting protection grounding system.