1.
In LTE, OFDM transmission is describer in
Correct Answer
A. Release 8
2.
Flexible bandwidth assignment in LTE supports
Correct Answer
C. TDMA and FDMA
Explanation
Flexible bandwidth assignment in LTE supports both TDMA and FDMA. TDMA (Time Division Multiple Access) is a technique that divides the available frequency into time slots, allowing multiple users to share the same frequency band by transmitting in different time slots. FDMA (Frequency Division Multiple Access) divides the available frequency into different frequency bands, allowing multiple users to transmit simultaneously on different frequency bands. LTE's flexible bandwidth assignment allows for efficient utilization of the available spectrum by dynamically allocating time slots and frequency bands to users based on their needs, ensuring optimal use of the resources and enhancing overall network capacity.
3.
A resource block in LTE has
Correct Answer
A. A bandwidth of 180 kHz and a duration of 1 ms
Explanation
In LTE, a resource block refers to the smallest unit of allocation in the frequency domain. It has a bandwidth of 180 kHz, which means it can accommodate a certain amount of data. The duration of a resource block is 1 ms, indicating the time it takes to transmit the data within that bandwidth. Therefore, the correct answer is that a resource block in LTE has a bandwidth of 180 kHz and a duration of 1 ms.
4.
The advantage of DFTS-OFDM over OFDM is
Correct Answer
B. Reducing cubic metric for uplink transmission and enabling higher terminal power amplifier efficiency
Explanation
DFTS-OFDM has an advantage over OFDM because it reduces the cubic metric for uplink transmission and enables higher terminal power amplifier efficiency. This means that DFTS-OFDM is able to improve the efficiency of power amplifiers used in transmitting signals, leading to a reduction in the amount of distortion and interference in the uplink transmission. This ultimately results in better overall performance and higher efficiency in terms of power usage.
5.
The advantage of OFDM over DFTS-OFDM is
Correct Answer
A. Having higher spectrum efficiency
Explanation
OFDM (Orthogonal Frequency Division Multiplexing) has a higher spectrum efficiency compared to DFTS-OFDM (Discrete Fourier Transform Spread-OFDM). This means that OFDM can transmit more data within the available bandwidth, allowing for increased capacity and improved utilization of the frequency spectrum. By efficiently utilizing the spectrum, OFDM enables higher data rates and better overall performance in wireless communication systems.
6.
LTE is
Correct Answer
B. A packet switching system
Explanation
LTE stands for Long Term Evolution, which is a standard for wireless broadband communication. It is widely used for 4G networks. LTE is a packet switching system, which means that data is divided into small packets and transmitted over the network. This allows for more efficient use of network resources and faster data transfer speeds. Unlike circuit switching systems, which establish a dedicated connection for the duration of a call, packet switching systems can handle multiple connections simultaneously. Therefore, the correct answer is that LTE is a packet switching system.
7.
The number of packets required to perform hybrid ARQ with soft combining is
Correct Answer
A. Two or more packets
Explanation
Hybrid ARQ with soft combining is a technique that combines multiple packets to improve the reliability of data transmission. In this technique, if errors are detected in a packet, instead of discarding it, the receiver stores the packet and combines it with subsequent packets to recover the original data. Therefore, to perform hybrid ARQ with soft combining, two or more packets are required to be transmitted.
8.
In inter-cell interference coordination ICIC two neighboring base stations cannot use the same frequency bands to communicate with a terminal
Correct Answer
B. False
Explanation
In inter-cell interference coordination (ICIC), neighboring base stations can use the same frequency bands to communicate with a terminal. ICIC techniques are designed to mitigate interference between adjacent cells, allowing them to share the same frequency resources efficiently. This helps to improve overall network capacity and performance. Therefore, the statement that two neighboring base stations cannot use the same frequency bands in ICIC is false.
9.
The number of packets required to perform hybrid ARQ is
Correct Answer
B. One packet
Explanation
Hybrid ARQ (Automatic Repeat Request) is a communication protocol that combines both forward error correction and retransmission techniques to ensure reliable data transmission. In the context of this question, the correct answer is "one packet" because hybrid ARQ can achieve error correction and retransmission with just a single packet. This is possible by including redundancy in the packet itself, allowing the receiver to detect and correct errors without the need for additional packets.
10.
At a low SINR scenario, multiple antennas should be used as
Correct Answer
B. Receive and transmit diversity
Explanation
In a low SINR (Signal-to-Interference-plus-Noise Ratio) scenario, the signal quality is poor and the chances of interference and noise are high. By using multiple antennas, such as in MIMO (Multiple-Input Multiple-Output) systems, both receive and transmit diversity can be achieved. Receive diversity helps in improving the signal quality by combining the signals received from multiple antennas, reducing the impact of interference and noise. Transmit diversity, on the other hand, allows the transmitter to send multiple versions of the same signal from different antennas, increasing the chances of the receiver capturing a good quality signal. Therefore, using multiple antennas in a low SINR scenario improves the overall performance and reliability of the communication system.
11.
At a high SINR scenario, multiple antennas should be used as
Correct Answer
A. MIMO
Explanation
In a high SINR scenario, using multiple antennas through MIMO (Multiple-Input Multiple-Output) technology can improve the overall system performance. MIMO allows for the transmission and reception of multiple data streams simultaneously, increasing the data rate and improving the overall signal quality. By using multiple antennas, MIMO can achieve spatial multiplexing, which helps to combat fading and interference, resulting in a more robust and reliable wireless communication system. Additionally, MIMO can also provide transmit diversity, where multiple antennas are used to transmit the same signal, enhancing the signal strength and reducing the impact of fading.
12.
Correct Answer
A. This image refers to frequency division duplex FDD
13.
Correct Answer
B. This image refers to time division duplex TDD
14.
Correct Answer
C. This image refers to half duplex FDD
15.
LTE supports different bandwidths on both uplink and down link (1MHz to 20 MHz). •On the contrary WCDMA requires a bandwidth of 5MHz and HSPA requires a bandwidth of multiples of 5 MHz.
Correct Answer
A. True
Explanation
LTE supports different bandwidths on both uplink and downlink, ranging from 1MHz to 20MHz. This is in contrast to WCDMA, which requires a fixed bandwidth of 5MHz, and HSPA, which requires a bandwidth that is a multiple of 5MHz. Therefore, the statement is true.
16.
A terminal position can be determined by measuring special reference signals transmitted regularly from different cell sites. This feature is introduced in
Correct Answer
B. LTE release 9
Explanation
LTE release 9 introduced the feature of determining a terminal position by measuring special reference signals transmitted regularly from different cell sites. This means that with LTE release 9, it became possible to accurately determine the location of a terminal device by analyzing the signals received from nearby cell sites.
17.
IMT-Advanced is fulfilled in
Correct Answer
C. LTE release 10
Explanation
IMT-Advanced, also known as 4G, is fulfilled in LTE release 10. This means that LTE release 10 meets the requirements and specifications set by the International Telecommunication Union (ITU) for 4G technology. LTE release 8 and 9 may not fully meet these requirements, hence they are not the correct answers.
18.
LTE-Advanced consists of ,up to, ___________release 8 aggregated carriers.
Correct Answer
B. Five
Explanation
LTE-Advanced is a mobile communication standard that allows for higher data rates and improved network performance. It achieves this by aggregating multiple carriers, or frequency bands, to increase the available bandwidth. The question asks how many carriers can be aggregated in LTE-Advanced, and the correct answer is "five". This means that LTE-Advanced can combine up to five different carriers from release 8 to achieve higher data speeds and better network performance.
19.
LTE-Advanced can provide peak data rate of _______ for uplink and ____________ for downlink
Correct Answer
A. 3 Gbit/s 1.5 Gbit/s
Explanation
LTE-Advanced is a mobile communication standard that offers higher data rates compared to its predecessor, LTE. The given answer states that LTE-Advanced can provide a peak data rate of 3 Gbit/s for the uplink and 1.5 Gbit/s for the downlink. This means that users can experience faster upload speeds of up to 3 Gbit/s and faster download speeds of up to 1.5 Gbit/s when using LTE-Advanced technology.
20.
Peak data rate requirements for IMT-Advanced are _______ for uplink and ____________ for downlink
Correct Answer
B. 600 Mbit/s 270 Mbit/s
Explanation
The peak data rate requirements for IMT-Advanced are 600 Mbit/s for uplink and 270 Mbit/s for downlink. This means that the maximum data transfer speed for uploading data is 600 Mbit/s, while the maximum speed for downloading data is 270 Mbit/s. These requirements indicate the capacity and speed at which data can be transmitted in the IMT-Advanced system.
21.
Carrier aggregation feature is introduced in LTE
Correct Answer
C. Release 10
Explanation
Carrier aggregation is a feature introduced in LTE release 10. This feature allows multiple LTE carriers to be combined, increasing the overall bandwidth and improving network performance. By aggregating multiple carriers, users can experience faster download and upload speeds, reduced latency, and improved network capacity. This feature is particularly useful in areas with high data traffic and congestion, as it allows for better utilization of available spectrum resources.
22.
Uplink spatial multiplexing feature is introduced in LTE
Correct Answer
C. Release 10
Explanation
The uplink spatial multiplexing feature was introduced in release 10 of LTE. This feature allows multiple users to transmit data simultaneously on the uplink channel, increasing the overall capacity and efficiency of the network. It utilizes multiple antennas at the base station to separate and decode the signals from different users, improving the system's ability to handle high data traffic.
23.
Dual-layer beam forming feature is introduced in LTE
Correct Answer
B. Release 9
Explanation
The dual-layer beamforming feature was introduced in LTE release 9. This feature allows for the use of multiple antennas to create focused beams of signal, improving the overall performance and coverage of the LTE network. This enhancement in release 9 helps to increase the capacity and efficiency of the LTE system, providing better data rates and improved user experience.
24.
Multi-antenna support feature is introduced in LTE
Correct Answer
A. Release 8
Explanation
The correct answer is release 8. The introduction of the multi-antenna support feature in LTE occurred in release 8.