esa-sceva/satcom-mcqa huggingface dataset:
Topic: Wireless communication systems
Question: What is the purpose of IPv6 WLL access validation in this scenario?
Option 1: IPv6 WLL access validation of the connection between Windows XP/Linux PCs
and a server on the Central LAN segment via Wireless Local Loop (WLL) using
IPv6 protocol.
Option 2: To verify the connectivity between client PCs (Windows XP/Linux) and a server over Wireless Local Loop using the IPv6 protocol.
Option 3: To test only IPv4 connectivity between client PCs and the server.
Option 4: To convert IPv6 packets into analog signals for WLL transmission.
Answer: Option1
Topic: IP over satellite
Question: What is the purpose of SNA/SDLC?
Option 1: Systems Network Architecture/ Synchronous Data Link Control (SNA/SDLC) guard against the loss of throughput by only requesting retransmission of blocks of data that have errors
detected by the receiver.
Option 2: Systems Network Architecture/ Synchronous Data Link Control (SNA/SDLC) calculates the gain of throughput of blocks of data that have errors
detected by the receiver.
Option 3: Systems Network Architecture/ Synchronous Data Link Control (SNA/SDLC) guard against the loss of throughput by only requesting retransmission of blocks of data that have errors
detected by the receiver.
Option 4: Systems Network Architecture/ Synchronous Data Link Control (SNA/SDLC) prevent throughput loss by requesting retransmission before any data errors occur.
Answer: Option1
Topic: SNR
Question: What is the purpose of the Shannon and Hartley capacity theorem?
Option 1: The Shannon and Hartley capacity theorem is used to determine the capacity boundary function between bandwidth
efficiencies.
Option 2: The Shannon and Hartley capacity theorem is used to determine the maximum bit rate C
over a band-limited channel giving a specific signal-to-noise ratio (S/N).
Option 3: The Shannon and Hartley capacity theorem is used to determine noiseless channels.
Option 4: The Shannon and Hartley capacity theorem is used to determine propagation delay and delay variation.
Answer: Option2
Topic: Link Budget
Question: What is the relationship between EIRP and transmit power if antenna gain is 10 dBi?
Option 1: EIRP = Transmit power + 10 dB
Option 2: EIRP = Transmit power - 10 dB
Option 3: EIRP = Transmit power x 10
Option 4: EIRP = Transmit power / 10
Answer: Option 1
Topic: Satellite gateway
Question: What is the role of a gateway earth station (GW) in a satellite communication system?
Option 1: The gateway earth station (GW) provides internetworking functions between the satellite network
and the Internet or a terrestrial network.
Option 2: It serves solely as a power amplifier for uplink signals, without routing or networking functions.
Option 3: It is used only for satellite-to-satellite communication, not for connecting to terrestrial networks.
Option 4: It functions exclusively as a remote user terminal for receiving broadcast content.
Answer: Option1
Topic: Satellite broadcasting
Question: What is the role of a meta-signalling virtual channel in an ATM network?
Option 1: A meta-signalling virtual channel is used to establish, check and release point-to-point and selective broadcast signalling virtual channels. It is bi-directional and permanent.
Option 2: To carry user data in a unidirectional temporary connection.
Option 3: To encrypt ATM cells without managing signalling.
Option 4: To provide only uplink connections from LECs to the BUS.
Option 5: To function as a multicast data channel rather than a signalling channel.
Answer: Option1
Topic: Gateway station
Question: What is the role of an FLS (Frame Link Subsystem) in a satellite communication system?
Option 1: It encapsulates IP packets into MPEG-2 frames, transmits them on a TDM carrier, base-band modulates the signal, and upconverts it to Ku-band frequencies for satellite transmission.
Option 2: It only performs RF amplification without any packet encapsulation.
Option 3: It demodulates Ku-band signals and converts them directly to analog video.
Answer: Option1
Topic: Uplink
Question: What is the role of antenna gain in uplink transmission?
Option 1: Increase bandwidth
Option 2: Reduce interference
Option 3: Increase effective radiated power
Option 4: Reduce satellite speed
Option 5: Increase latency
Answer: Option 3
Topic: Link availability
Question: what is the role of Database Description (DBD) messages?
Option 1: They include the sequence numbers of all link-state entries and are exchanged between routers to describe their link-state databases.
Option 2: They carry actual routing updates containing full link-state advertisements.
Option 3: They are used only to acknowledge the receipt of Hello packets.
Option 4: They are used to test the physical connectivity between routers.
Answer: Option1
Topic: 5G NTN
Question: What is the role of the satellite-based NTN Gateway (GW) in 5G NR satellite networks?
Option 1:  The satellite-based NTN Gateway (GW) supports all necessary functions to forward the signal of NR-Uu interface.
Option 2: It only amplifies the RF signal without handling any NR-Uu interface functions.
Option 3: It replaces the user equipment (UE) in the network, directly communicating with terrestrial nodes.
Option 4: It functions solely as a power regulator, unrelated to signal forwarding or interfaces.
Answer: Option1
Topic: Link Budget
Question: What is the significance of the noise figure in a receiver?
Option 1: Measure of receiver noise added to signal
Option 2: Signal gain
Option 3: Power attenuation
Option 4: Frequency shift
Answer: Option 1
Topic: Satellite broadcasting
Question: What is the trend in SDTV channel broadcasting in the Ku band as of 2018?
Option 1: The use of DVB-S2 is increasing, but around 50% of SDTV channels are still broadcast using DVB-S.
Option 2: All SDTV channels have completely switched to DVB-S2.
Option 3: DVB-S2 broadcasting is decreasing in favor of DVB-S.
Answer: Option1
Topic: Satellite User terminal
Question: What is the typical data rate supported by consumer-grade satellite user terminals?
Option 1: 1-10 kbps
Option 2: 100 kbps to 50 Mbps
Option 3: 1-5 Gbps
Option 4: 10-100 Mbps
Answer: Option 2
Topic: Satellite User terminal
Question: What is the typical transmit power range in user terminals?
Option 1: Milliwatts to a few watts
Option 2: 100 to 500 watts
Option 3: 10 kW to 50 kW
Option 4: 1 MW and above
Answer: Option 1
Topic: Link Budget
Question: What is the typical value of thermal noise power density K in dB?
Option 1: -174 dBm/Hz
Option 2: -100 dBm/Hz
Option 3: -200 dBm/Hz
Option 4: -50 dBm/Hz
Option 5: 0 dBm/Hz
Answer: Option 1
Topic: Link Budget
Question: What is the unit of the received power in the link budget formula?
Option 1: The received power in the link budget formula is measured in decibel relative to 1 milliwatt (dBm).
Option 2: The received power in the link budget formula is measured in decibel relative to 1W, which
is stated as dBW.
Option 3: The received power in the link budget formula is measured in decibel relative to 1 joule.
Option 4: The received power in the link budget formula is measured in decibel relative to 1 volt (dBV).
Option 5: The received power in the link budget formula is expressed in linear watts (W).
Answer: Option2
Topic: Link Budget
Question: What is typically the first step in a link budget analysis?
Option 1: Determining receiver sensitivity
Option 2: Calculating path loss
Option 3: Estimating transmit power
Option 4: Defining data rate
Answer: Option 3
Topic: SNR
Question: What is usually the minimum acceptable SNR required for a reliable digital communication link?
Option 1: 0 dB
Option 2: 5 dB
Option 3: 10 dB
Option 4: 20 dB
Option 5: 30 dB
Answer: Option 3
Topic: Satellite Bandwidth
Question: What is X-band used for in satellite communications?
Option 1: X-band is a protected, highly stable band primarily used by military and government users for secure and mission-critical operations.
Option 2: X-band is mainly used for commercial direct-to-home (DTH) broadcasting and consumer Internet services.
Option 3: X-band is an unlicensed frequency band intended for public Wi-Fi and Bluetooth applications.
Option 4: X-band is used primarily for amateur radio satellite communications and hobbyist satellites.
Option 5: X-band is only used for Earth observation sensors, not for communication purposes.
Answer: Option1
Topic: Link Budget
Question: What limits the maximum propagation path for a single antenna?
Option 1: For a single antenna, the 
maximum path of propagation is limited by the distance to the RF horizon.
Option 2: The maximum path is limited only by transmitter power, regardless of the horizon.
Option 3: The maximum path is limited by antenna color or material.
Answer: Option1
Topic: Non-Terrestrial Networks
Question: What modulation scheme is commonly preferred for satellite communications in NTN?
Option 1: QPSK
Option 2: ASK
Option 3: FSK
Option 4: PAM
Option 5: PWM
Answer: Option 1
Topic: DVB-S2
Question: What modulation schemes are supported by DVB-S2?
Option 1: QPSK, 8PSK
Option 2: QPSK, 16QAM
Option 3: BPSK, QPSK
Answer: Option 1
Topic: Inter satellite Link
Question: what must be included as part of the “trust infrastructure” for proper operation?
Option 1: The transport gateway must be included as part of the trust infrastructure to operate.
Option 2: Only the end-user devices need to be included in the trust infrastructure, not the transport gateway.
Option 3: The trust infrastructure functions independently of any transport gateways.
Option 4: IP-level security eliminates the need for any form of trust infrastructure between connected networks.
Option 5: The transport gateway is used only for routing IP packets, with no impact on the trust infrastructure.
Answer: Option1
Topic: BER
Question: What often causes an increase in BER?
Option 1: High SNR
Option 2: Low noise
Option 3: Interference
Option 4: Perfect channel
Option 5: Synchronization
Answer: Option 3
Topic: 3gpp
Question: What proprietary Device-to-Device (D2D) services are already in the market?
Option 1: Proprietary D2D services that use non-3GPP radio access technologies and established MSS spectrum in the S- and L-bands have already been commercially deployed.
Option 2: Proprietary D2D services operate exclusively on 3GPP-compliant radio interfaces and have not yet been commercially deployed.
Option 3: D2D services in the S- and L-bands are still under experimental testing, with no commercial availability.
Answer: Option1
Topic: DVB-S2X
Question: What purpose is DVB-S2 structured around?
Option 1: DVB-S2 is structured as a toolkit, thus also enabling
 the use of mass market products for professional or niche applications.
Option 2: DVB-S2 is restricted to mass-market consumer products only, and cannot support professional applications.
Option 3: DVB-S2 is designed exclusively for military or niche applications, not for mass-market use.
Answer: Option1
Topic: DVB-S2
Question: What quality standard is the DVB-S system designed to achieve?
Option 1: The DVB-S system is designed to provide so-called ‘quasi error free’ (QEF) quality.
Option 2: The DVB-S system guarantees absolutely error-free transmission under all conditions.
Option 3: The DVB-S system provides highly lossy transmission, with frequent packet errors tolerated.
Option 4: The DVB-S system only provides analog signal quality, not digital QEF performance.
Option 5: The DVB-S system achieves full error correction without using FEC, relying solely on retransmissions.
Answer: Option1
Topic: TCP over satellite
Question: What role do TCP congestion avoidance mechanisms play in satellite networks with terrestrial connections?
Option 1: They remain active over terrestrial links, ensuring full TCP reliability and end-to-end flow control.
Option 2: They are disabled entirely, as satellite links handle congestion separately.
Option 3: They replace TCP reliability with UDP-style best-effort delivery.
Option 4: They only operate on uplink traffic from satellites to terminals.
Answer: Option1
Topic: Satellite gateway
Question: What role does the gateway play in link budget calculation?
Option 1: Transmission power only
Option 2: Reception sensitivity only
Option 3: Both transmission power and reception sensitivity
Option 4: Frequency allocation
Answer: Option 3
Topic: 5G NTN
Question: What role does the NTN Gateway at the end of the feeder link perform?
Option 1: If the airborne platform has the base station (gNB) on board (regenerative payload), then the NTN Gateway at the end of the feeder link can be a router to the Core network which connects to the public network.
Option 2: If the airborne platform has the base station (gNB) on board, the NTN Gateway at the end of the feeder link acts only as a radio relay and cannot function as a router to the Core network.
Option 3: When the airborne platform carries the gNB (regenerative payload), the NTN Gateway must perform RAN-level functions such as scheduling and radio resource management, rather than routing to the Core network.
Option 4: If the gNB is located on the airborne platform, the feeder link typically terminates directly at the user equipment (UE) instead of passing through an NTN Gateway.
Answer: Option1
Topic: Link Budget
Question: What role does the receiver's sensitivity play in a link budget?
Option 1: The receiver’s sensitivity specifies the minimum RF input power required to produce a useable output signal.
Option 2: The receiver’s sensitivity indicates the maximum RF power the receiver can handle without damage.
Option 3: The receiver’s sensitivity defines the average transmitted power from the satellite or base station.
Option 4: The receiver’s sensitivity measures the signal-to-noise ratio at the transmitter.
Answer: Option1
Topic: Wireless communication systems
Question: What services does the INMARSAT Global Area Network (GAN) provide via a small portable Mobile Satcom Unit (MSU)?
Option 1: It offers voice telephony and high-speed wireless data transmission at 64 kbit/s via a small portable MSU roughly the size of a notebook computer.
Option 2: It provides only voice telephony, with no data transmission capability.
Option 3: It delivers data transmission at speeds exceeding 1 Gbit/s, requiring large, stationary terminals.
Option 4: It supports satellite TV broadcasting, but not telephony or mobile data.
Answer: Option1
Topic: IP over satellite
Question: What technique improves TCP performance over satellite?
Option 1: Larger packets
Option 2: Window scaling
Option 3: Reduced header size
Option 4: Fixed route
Answer: Option 2
Topic: Link Budget
Question: What terms does the link margin consist of? 
Option 1: The margin is usually introduced by increasing a combination of the transmit power, transmit
 antenna gain, and receive antenna gain.
Option 2: The margin is introduced by reducing transmit power and antenna gains.
Option 3: Margin is added by changing the modulation scheme only, without affecting power or antennas.
Option 4: Margin is achieved by reducing receiver sensitivity, not by increasing power or gain.
Option 5: Margin is independent of transmit or receive parameters and is determined solely by atmospheric conditions.
Answer: Option1
Topic: Wireless communication systems
Question: What type of antenna is commonly used in wireless communication systems?
Option 1: Parabolic dish
Option 2: Dipole
Option 3: Horn antenna
Answer: Option 2
Topic: Circular Polarization
Question: What type of circular polarization rotates clockwise when viewed from the receiver?
Option 1: Left-hand
Option 2: Right-hand
Option 3: Vertical
Option 4: Horizontal
Option 5: Elliptical
Answer: Option 2
Topic: DVB-S2X
Question: What type of coding does DVB-S2X use?
Option 1: LDPC and BCH
Option 2: Turbo and Reed-Solomon
Option 3: Convolutional codes
Option 4: LDPC and Turbo
Answer: Option 1
Topic: Onboard processing
Question: What type of network access do Satellite Terminals (RCST) provide?
Option 1: Satellite Terminals (RCST) provide single PC or LANs with the access to the network.
Option 2: Satellite Terminals (RCST) provide access only to individual IoT sensors.
Option 3: Satellite Terminals (RCST) provide network access directly through a mobile cellular core.
Answer: Option1
Topic: Link availability
Question: What type of signals are used in uplinks, downlinks, and intersatellite links in satellite communication systems?
Option 1: Uplinks and downlinks consist of radio frequency modulated carriers, while intersatellite links can
be either radio frequency or optical.
Option 2: Uplinks and downlinks use optical signals, while intersatellite links are only radio frequency-based.
Option 3: Uplinks use acoustic waves, while downlinks rely on infrared transmissions.
Answer: Option1
Topic: DVB-S2
Question: What types of input sequences can a DVB-S2 system handle?
Option 1: Single or multiple MPEG Transport Streams (TSs), single or multiple generic streams, either packetized or continuous.
Option 2: Only single MPEG TS streams in continuous mode.
Option 3: Only analog TV signals without packetization.
Option 4: Only a single generic stream in packetized mode.
Option 5: Only non-packetized proprietary video formats.
Answer: Option1
Topic: DVB-S2
Question: What types of input sequences can DVB-S2 accommodate?
Option 1:  Depending on the application, DVB-S2 input sequences  may be single or multiple MPEG TSs, single or Multiple  generic streams, either packetized or continuous.
Option 2: DVB-S2 input sequences are restricted to a single MPEG transport stream only.
Option 3: DVB-S2 input sequences support packetized streams only, excluding continuous streams.
Option 4: DVB-S2 input sequences can only be analog audio/video signals, not digital transport streams.
Option 5: DVB-S2 input sequences are limited to IP packets exclusively, without support for MPEG TS or generic streams.
Answer: Option1
Topic: DVB-S2
Question: What types of input stream formats does DVB-S2 accommodate?
Option 1: DVB-S2 accommodates any input stream format, including single or multiple MPEG transport streams, IP as well as ATM packets, continuous bit-streams.
Option 2: DVB-S2 accommodates only single MPEG transport streams, excluding IP or ATM packets.
Option 3: DVB-S2 supports IP packets exclusively, and cannot handle MPEG transport streams.
Option 4: DVB-S2 accommodates continuous bit-streams only, not packetized formats like IP or ATM.
Answer: Option1
Topic: NTN
Question: What types of satellite access tracking will be implemented in satellite-based NTN systems?
Option 1: Satellite-based NTN will implement position-based and fixed tracking area (TA) 
satellite access. 
Option 2: Randomized and dynamic frequency hopping access only.
Option 3: Time-division multiplexing (TDM) without any position or tracking area considerations.
Answer: Option1
Topic: Carrier-to-noise ratio
Question: What types of signals are used in satellite communication links?
Option 1: Uplinks and downlinks consist of radio-frequency modulated carriers, while intersatellite links
can be either radio frequency or optical.
Option 2: Uplinks and downlinks use optical signals only, while intersatellite links use acoustic signals.
Option 3: Uplinks and downlinks are unmodulated DC signals, while intersatellite links are microwave only.
Option 4: All satellite links, including intersatellite links, use only optical frequencies.
Option 5: Uplinks use magnetic signals, and downlinks use infrared transmissions.
Answer: Option1
Topic: Onboard processing
Question: What was the capacity and operation of the first Intelsat-V satellite?
Option 1: The first Intelsat-V satellite achieved capacity of 12,000 circuits with FDMA and
TDMA operations.
Option 2: The first Intelsat-V satellite achieved capacity of 12,000 circuits without any multiple access technique, operating on a single channel only.
Option 3: The first Intelsat-V satellite achieved a capacity of 24,000 circuits with FDMA and TDMA operations.
Option 4: The first Intelsat-V satellite achieved capacity of 12,000 circuits using CDMA and FDMA operations.
Answer: Option1
Topic: DVB-S2
Question: What was the focus of the DVB-S2 FEC selection process?
Option 1: TheDVB-S2 FEC selection process, based on computer simulations, compared seven proposals over the AWGN channel, all using recursive decoding techniques.
Option 2: The DVB-S2 FEC selection process was evaluated only through field experiments, without simulations.
Option 3: The DVB-S2 FEC selection process compared proposals over fading channels only, ignoring AWGN channels.
Option 4: The DVB-S2 FEC selection process did not use recursive decoding, relying solely on one-shot decoding techniques.
Answer: Option1
Topic: Beamforming
Question: When designing a beamforming system, why are array size and instantaneous bandwidth evaluated?
Option 1: To check whether the use of phase shifters will provide adequate performance or if true time delay units (TDUs) are required.
Option 2: To determine if mechanical steering is needed instead of electronic steering.
Option 3: To calculate the total transmit power for the antenna array.
Option 4: To estimate the Doppler shift of the received signal.
Option 5: To determine the polarization losses of the antenna.
Answer: Option1
Topic: Link Budget
Question: When does packet loss become a serious problem in a network?
Option 1: When the percentage of lost packets exceeds a threshold or when losses occur in large bursts.
Option 2: Only when a single packet is lost, regardless of the overall loss rate.
Option 3: When all packets are delivered without any loss.
Answer: Option1
Topic: Link Budget
Question: When is a link considered to have a line-of-sight (LOS) path of propagation?
Option 1: For a link to be considered as having a line-of-sight path of propagation, the 
distance between the transmitting and receiving antennas must be equal to or less than the maximum line-of-sight path distance.
Option 2: A link is considered LOS only if the antennas are separated by more than the RF horizon distance.
Option 3: A link is LOS when obstructions such as hills or buildings block the direct path.
Option 4: A link is LOS when the antennas are not aligned, relying on reflected signals.
Answer: Option1
Topic: BER
Question: When is BER a reliable measure in Handover initialization?
Option 1: The Bit Error Rate
(BER) experienced in the modulation of the transferred digital signals is the most reliable measure of quality in inter-system HO initialization, when network level quantities lead to misleading results.
Option 2: The Bit Error Rate
(BER) experienced in the demodulation of the received digital signals is the most reliable measure of quality in inter-system HO initialization in the presence of interference, when power level measurements may lead to misleading results.
Option 3: The Bit Error Rate
(BER) experienced in the satellite is the most reliable measure of quality in communication systems when power levels are decreasing.
Answer: Option2
Topic: Satellite Bandwidth
Question: Where can orthogonal frequency division multiplexing (OFDM) be used?
Option 1: OFDM is implemented where satellites are used for broadcasting of audio programmes to mobile receivers (digital
audio broadcasting, or DAB).
Option 2: OFDM is implemented to combat the time dispersion due to multipath,
frequently encountered over mobile satellite channels.
Option 3: It is used to separate signals by the gamma filters in order to compensate for the non-linear response of the receiving cathode-ray tube.
Option 4: OFDM is used for the emission of digitally encoded audio signals.
Answer: Option1
Topic: 3gpp
Question: Which 3GPP group defines protocol specs?
Option 1: TSG-RAN
Option 2: TSG-SA
Option 3: TSG-CT
Answer: Option 1
Topic: 3gpp
Question: Which 3GPP release first standardized LTE?
Option 1: Release 7
Option 2: Release 8
Option 3: Release 9
Answer: Option 2
Topic: 3gpp
Question: Which 3GPP release introduced VoLTE?
Option 1: Release 8
Option 2: Release 9
Option 3: Release 10
Answer: Option 3
Topic: Onboard processing
Question: Which access scheme is used for the return link in DVB-S/RCS systems?
Option 1: The return link access scheme in DVB-S/RCS systems is MF-TDMA.
Option 2: FDMA (Frequency Division Multiple Access) only.
Option 3: CDMA (Code Division Multiple Access) exclusively.
Option 4: ALOHA protocol without frequency or time division.
Answer: Option1