SBCA Network Design 2

Question 1

In a VSAT star topology network, what is the primary role of the hub station?

Accepted Answer

To aggregate all remote site traffic and connect to the terrestrial network

Answer

In a star topology VSAT network, the hub station aggregates all inbound traffic from remote sites and connects the network to terrestrial infrastructure such as the internet or private WAN.

Question 2

What is the key advantage of a mesh topology satellite network over a star topology?

Accepted Answer

Lower latency for site-to-site communications

Answer

Mesh topology allows direct site-to-site links, eliminating the double-hop latency (approximately 500ms round-trip) required when all traffic must pass through a central hub.

Question 3

Which modulation scheme provides the highest spectral efficiency in modern satellite broadband networks?

Accepted Answer

16APSK

Answer

16APSK offers the highest spectral efficiency among the listed options, delivering approximately 4 bits per symbol, though it requires higher Eb/N0 and is used on high-quality links with sufficient CNR.

Question 4

A satellite network designer must plan for rain fade on a Ku-band link. Which design technique directly compensates for rain attenuation?

Accepted Answer

Adaptive coding and modulation (ACM)

Answer

ACM dynamically adjusts the modulation and coding rate based on real-time link conditions, reducing throughput during rain fade to maintain link availability.

Question 5

What does the term 'figure of merit' (G/T) represent in satellite terminal design?

Accepted Answer

The ratio of antenna gain to system noise temperature

Answer

G/T (Gain-to-noise Temperature ratio) is the figure of merit for a receive system, expressing antenna gain relative to system noise temperature in dB/K.

(SBCA) Satellite Broadcasting and Communications Association Certification Practice Test

(SBCA) Satellite Broadcasting and Communications Association Certification Practice Test

SBCA Network Design 2