SSPI Satellite Network Design & Operations 3

Question 1

In a VSAT star topology, what is the function of the hub earth station?

Accepted Answer

It acts as the central gateway that routes traffic between remote terminals and the terrestrial network

Answer

In a star topology, all remote VSAT terminals communicate through the central hub, which manages routing, protocol conversion, and network access.

Question 2

What distinguishes a regenerative (processing) satellite payload from a bent-pipe transponder?

Accepted Answer

A regenerative payload demodulates, processes, and re-modulates the signal onboard rather than simply amplifying and retransmitting

Answer

Regenerative payloads perform onboard signal processing, enabling separate uplink and downlink optimization and reducing end-to-end latency.

Question 3

What is the primary purpose of a satellite's apogee kick motor (AKM)?

Accepted Answer

To circularize the orbit at geostationary altitude after launch vehicle injection

Answer

The AKM fires at apogee of the transfer orbit to raise perigee and circularize the satellite into geostationary orbit.

Question 4

Which multiple access technique assigns dedicated time slots to each earth station transmitting through a shared transponder?

Accepted Answer

TDMA

Answer

TDMA divides the transponder's time into sequential slots, with each station transmitting burst traffic during its assigned slot.

Question 5

Rain fade is most severe at which frequency bands used for satellite communications?

Accepted Answer

Ka-band (26.5-40 GHz)

Answer

Rainfall attenuation increases significantly with frequency, making Ka-band systems most susceptible to rain fade.

(SSPI) Society of Satellite Professionals International Certification Practice Test