Network Design Flashcards
7 cards from real SBCA practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Network Design flashcards as text
What is the primary purpose of an uplink power control (UPC) system in a satellite network?
Answer: To compensate for atmospheric attenuation and maintain constant power flux density at the satellite
UPC automatically increases earth station transmit power during rain fade or atmospheric attenuation events to maintain a stable carrier level at the satellite transponder input.
In satellite network design, what does 'transponder loading' refer to?
Answer: The aggregate power and bandwidth utilization relative to transponder capacity
Transponder loading describes how much of the transponder's available power and bandwidth is being consumed by carriers, typically expressed as a percentage of total capacity.
Which access method is best suited for a satellite network where thousands of terminals send very short, infrequent data bursts?
Answer: ALOHA or slotted ALOHA random access
ALOHA-based random access is ideal for large populations of terminals with bursty, infrequent transmissions where assigning dedicated channels would waste most of the capacity.
A satellite network planner must prevent interference between adjacent satellite systems. What is the primary coordination mechanism used internationally?
Answer: ITU Radio Regulations coordination procedures and interference criteria
The ITU Radio Regulations establish mandatory coordination procedures requiring satellite operators to coordinate with potentially affected networks before bringing a new satellite into service.
In a DVB-RCS2 return link design, what determines the maximum number of terminals that can share a single return carrier?
Answer: The aggregate traffic demand relative to carrier symbol rate and coding efficiency
The carrier's total capacity (determined by symbol rate, modulation, and coding rate) must accommodate the aggregate traffic from all sharing terminals, setting the practical limit on terminal count.
What is the effect of antenna pointing error on satellite link performance?
Answer: It reduces the effective gain of the antenna, degrading both EIRP and G/T
Mispointing causes the antenna to operate off its peak gain point, reducing both transmit EIRP and receive G/T, which degrades the link budget on both uplink and downlink.
In satellite network design, what is a 'bent-pipe' transponder architecture?
Answer: A transponder that simply amplifies and frequency-converts the received signal before retransmitting
A bent-pipe transponder is a transparent repeater that receives, amplifies, and frequency-converts the signal without any onboard demodulation, processing, or routing.