S-BAND / UHF TRANSCEIVER – USER MANUAL
ENDUROSAT
7
5
SYSTEM DESCRIPTION
The
S-band
transceiver works in the frequency range 2400 – 2480 MHz with GFSK modulation. In
the core of this S-band transceiver there is a high performance IC which is a zero-IF transceiver. It is
responsible for the output signal forming and also down converting and demodulating of the input
signal. It contains radio controller and packet manager which makes it very flexible. For its integrated
frequency synthesizer and system timing it uses a 26 MHz reference signal. In the Tx signal chain
there is a RF driver amplifier followed by a PA which boosts the output signal up to 2 W. In the Rx
signal chain there is a LNA followed by BPF. There is also
а
Tx/Rx switch since the device is half-
duplex. The communication with the OBC (or payload) is accomplished by SPI interface of the MCU.
The supply voltage to the transceiver must be 5V ±0.25V and is directly connected to the PA. There
is a LDO, which reduces the voltage for the rest of the schematic to 3.3 V. The connector used is
PC-104 suitable for stackable configurations. The connector for the antenna is MCX.
Figure 2 - Block Diagram of the S-Band transceiver
