Download WiSE 2017 Curriculum Exam and more Exams Technology in PDF only on Docsity!
Question 1. What is the primary function of a wireless transmitter in a communication system? A) To encode information into radio signals B) To amplify incoming signals C) To decode received signals D) To store data temporarily Answer: A Explanation: The transmitter encodes information onto radio signals for transmission over the wireless channel, enabling communication with receivers. Question 2. Which component in a wireless communication system is responsible for receiving signals from the channel? A) Transmitter B) Modulator C) Receiver D) Encoder Answer: C
Explanation: The receiver captures incoming radio signals from the channel and demodulates or decodes them to retrieve the transmitted information. Question 3. Which wireless technology is primarily used for short- range device pairing and data exchange? A) Satellite communication B) Bluetooth C) Cellular networks D) Wi-Fi Answer: B Explanation: Bluetooth is designed for short-range wireless communication between devices like phones, headsets, and peripherals. Question 4. Which spectrum management principle involves allocating specific frequency bands to different services to prevent interference? A) Spectrum reuse B) Spectrum licensing
A) Wavelength B) Frequency C) Amplitude D) Polarization Answer: B Explanation: Frequency measures how many cycles of the wave pass a point per second, fundamental in radio wave characteristics. Question 7. In radio propagation, which phenomenon occurs when waves bend around obstacles? A) Reflection B) Refraction C) Diffraction D) Scattering Answer: C Explanation: Diffraction is the bending of waves around obstacles, enabling signals to reach areas blocked by physical barriers. Question 8. Which path loss model is based on the free-space propagation principle?
A) Log-distance path loss model B) Friis transmission equation C) Rayleigh fading model D) Shadowing model Answer: B Explanation: The Friis transmission equation calculates free-space path loss based on distance and frequency, assuming no obstacles. Question 9. Which fading phenomenon results from the constructive and destructive interference of multipath signals? A) Shadowing B) Multipath fading C) Doppler shift D) Path loss Answer: B Explanation: Multipath fading occurs when signals arrive at the receiver via multiple paths, causing fluctuations in received signal strength. Question 10. How does Doppler shift affect wireless signals?
Question 12. In digital communication, what does the Shannon theorem relate to? A) Error correction capabilities B) Maximum data rate of a channel C) Power efficiency of modulation schemes D) Antenna radiation patterns Answer: B Explanation: The Shannon theorem establishes the maximum achievable data rate (channel capacity) for a given bandwidth and noise level. Question 13. Which emerging wireless technology is primarily designed to provide ultra-high-speed data rates and low latency? A) 4G LTE B) 5G C) Bluetooth 5. D) Wi-Fi 4 Answer: B
Explanation: 5G offers significantly higher data rates and lower latency compared to previous generations, supporting advanced applications. Question 14. Which wireless connectivity technology is most suitable for low-power, long-range IoT sensor networks? A) Wi-Fi B) Bluetooth C) LPWAN (e.g., LoRa, NB-IoT) D) Millimeter-wave Answer: C Explanation: LPWAN technologies like LoRa and NB-IoT are optimized for low-power, long-range communication in IoT deployments. Question 15. What is a key characteristic of Wireless Sensor Networks (WSNs)? A) High data rate transmission over long distances B) Deployment of numerous low-power sensor nodes for environmental monitoring
B) Dynamic Spectrum Access C) Spectrum licensing D) Frequency hopping Answer: B Explanation: Dynamic Spectrum Access allows secondary users to utilize unused spectrum segments opportunistically, improving spectrum efficiency. Question 18. Which communication method uses visible light to transmit data? A) NFC B) VLC C) Bluetooth D) WiMAX Answer: B Explanation: Visible Light Communication (VLC) employs LED lights to transmit data through modulated visible light signals. Question 19. Near-Field Communication (NFC) primarily operates within what approximate distance?
A) Several kilometers B) Up to 10 meters C) A few centimeters to 4 centimeters D) Unlimited range with satellite support Answer: C Explanation: NFC is designed for short-range communication, typically within a few centimeters, suitable for contactless payments and data exchange. Question 20. Which standard is associated with Wi-Fi and has evolved through standards like a/b/g/n/ac/ax? A) IEEE 802. B) IEEE 802. C) IEEE 802. D) IEEE 802. Answer: B Explanation: IEEE 802.11 defines Wi-Fi standards, with successive amendments improving speed, range, and security.
Question 23. Which cellular generation introduced digital cellular networks with improved voice quality and capacity? A) 1G B) 2G C) 3G D) 4G Answer: B Explanation: 2G cellular systems introduced digital transmission, enabling better voice quality and capacity over analog systems. Question 24. Which multiple access technique divides the frequency spectrum into separate channels assigned to different users? A) FDMA B) TDMA C) CDMA D) OFDMA Answer: A
Explanation: Frequency Division Multiple Access (FDMA) assigns distinct frequency bands to users, allowing simultaneous communication. Question 25. Which technique in cellular networks manages user mobility by transferring ongoing calls between base stations? A) Handover B) Paging C) Registration D) Tunneling Answer: A Explanation: Handover allows seamless transfer of active calls during user movement across cell boundaries, maintaining connectivity. Question 26. Which version of IP was specifically designed to support mobility features in networks? A) IPv B) IPv C) IPv D) IPv4-mapped IPv
Answer: A Explanation: Wireless Application Protocol (WAP) enables mobile devices to access internet services with optimized protocols. Question 29. Which modulation technique encodes data by varying the phase of the carrier wave? A) ASK B) FSK C) PSK D) QAM Answer: C Explanation: Phase Shift Keying (PSK) encodes data by altering the phase of the carrier signal, common in digital modulation. Question 30. Orthogonal Frequency Division Multiplexing (OFDM) is especially resistant to which type of interference? A) Multipath fading B) Thermal noise C) Jamming D) Frequency hopping interference
Answer: A Explanation: OFDM's multicarrier structure makes it robust against multipath fading by transmitting data over many orthogonal subcarriers. Question 31. Which antenna type is most commonly used in portable wireless devices due to its compact size? A) Dipole antenna B) Patch antenna C) Yagi antenna D) Parabolic dish Answer: B Explanation: Patch antennas are compact, inexpensive, and suitable for integration into portable wireless devices. Question 32. MIMO technology enhances wireless communication by using multiple antennas to achieve what? A) Larger coverage area B) Higher data rates through spatial multiplexing C) Lower power consumption
D) Power control Answer: A Explanation: Pilot symbols are inserted periodically to facilitate channel estimation at the receiver. Question 35. Which security vulnerability involves an attacker intentionally transmitting signals to interfere with legitimate wireless communication? A) Eavesdropping B) Jamming C) Spoofing D) Man-in-the-middle attack Answer: B Explanation: Jamming involves transmitting signals to disrupt or block communication channels. Question 36. Which cryptographic method uses the same key for encryption and decryption? A) Asymmetric cryptography B) Symmetric cryptography
C) Hash functions D) Digital signatures Answer: B Explanation: Symmetric cryptography employs a single secret key for both encryption and decryption processes. Question 37. Which protocol provides mutual authentication and key management in Wi-Fi networks? A) WEP B) WPA C) WPA D) WPS Answer: C Explanation: WPA3 enhances security with improved authentication and key management protocols, including SAE (Simultaneous Authentication of Equals). Question 38. What is SNMP primarily used for in wireless network management? A) Data encryption
