Cellular networks (4G, 5G) in Computer Networks - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Understanding 4G LTE Technology

Which of the following best describes the main improvement 4G LTE brought compared to 3G networks?

A It increased data speeds and enabled IP-based communication.

B It introduced packet switching for voice calls only.

C It replaced all radio towers with satellite communication.

D It focused solely on improving battery life of devices.

💡 Hint

Think about what 4G LTE improved most for internet and communication.

4G LTE mainly improved data speeds and shifted communication to IP-based systems, unlike 3G which was more circuit-switched.

📋 Factual

intermediate

5G Frequency Bands

Which frequency range is commonly used by 5G networks to achieve very high data rates but with limited coverage?

A Millimeter wave bands above 24 GHz

B Mid-band frequencies around 2-6 GHz

C Below 100 MHz bands

D Sub-1 GHz bands

💡 Hint

Consider which frequencies allow very fast data but don't travel far.

Millimeter wave bands above 24 GHz offer very high data rates but have limited range and penetration.

🔍 Analysis

advanced

Comparing 4G and 5G Latency

Given that 4G networks typically have latency around 50 milliseconds and 5G aims for latency as low as 1 millisecond, what is the practical impact of this reduction?

A It only improves battery life of mobile devices.

B It enables near real-time communication suitable for applications like remote surgery and autonomous driving.

C It allows for faster web page loading but no change in real-time applications.

D It increases the maximum number of connected devices but does not affect speed.

💡 Hint

Think about applications that need very fast response times.

Lower latency in 5G enables applications requiring near real-time responses, such as remote surgery and autonomous vehicles.

❓ Reasoning

advanced

5G Network Architecture Benefits

Which feature of 5G network architecture helps it support diverse use cases like IoT devices, enhanced mobile broadband, and ultra-reliable low latency communication?

A Replacing all base stations with Wi-Fi hotspots.

B Use of a single fixed frequency band for all services.

C Network slicing that creates multiple virtual networks on the same physical infrastructure.

D Limiting the number of connected devices to reduce congestion.

💡 Hint

Consider how one network can serve very different needs simultaneously.

Network slicing allows 5G to create multiple virtual networks tailored for different services on the same hardware.

❓ Comparison

expert

Impact of Massive MIMO in 5G

Massive MIMO (Multiple Input Multiple Output) is a key technology in 5G. What is its main advantage compared to traditional MIMO used in 4G?

A It only improves voice call quality without affecting data transmission.

B It uses fewer antennas to reduce hardware costs but lowers data rates.

C It replaces antennas with satellite links for better global coverage.

D It uses a large number of antennas to improve capacity, coverage, and spectral efficiency significantly.

💡 Hint

Think about how adding more antennas affects signal quality and capacity.

Massive MIMO uses many antennas to send and receive multiple data streams simultaneously, greatly improving network performance.