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Non-coherent S-band transponder

Omni coverage with QFH and AMH antennas

Altitude determination by GPS receiver

Down link / Telemetry data transmission

Carrier frequency: 2240 MHz PCM/BPSK

Payload data : 10 KBPS

Telemetry data : 1 KBPS

.

up link / Command reception

carrier frequency: 2030 MHz

PCM/FSK/FM

100 BPS

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Phase1: Tubesat

For Tubesat we are using Two patch antennas on

opposite directions for near omni coverage in S-band

frequency

Phase2: cubesat

We are using Quadrifilar helix(QFH) and null filling

antenna axial mode helix(AMH) for near omni (85%)

coverage in S-band frequency

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Crystal

/saw

Filter

LNA

IF AMP

AD8335

IF AMP

AD8335

DIPLEXER

POWER

COUPLER

QHA

AMH

ISOLATER ISOLATER

NRZ-S ,

TURBO CODED

DATA

BPSK

Tx.

MODPOWER

AMPLIFIER

S-BAND (VCO)

F/2

POWER

DIV

F/16

P.D.TCXO

LPF(AMP)

LIMITERFM DISCRIMINATOR

TO ONBOARD PROCESSING

AMP

40 dB DRIVER

+7dB

IC 741

2240 MHz

141.25 MHz

70 MHz

2030 MHz

70.75MHz

2240 MHz

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Axial mode Helix:Quadrifilar Helix:

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PATCH ANTENNA