CMT Network Technologies & Connectivity 2 — Questions and Answers
Question 1: A customer's phone shows full LTE bars but data speeds are extremely slow. What is the most likely cause?
- Faulty antenna connector
- Network congestion in the cell sector (Correct answer)
- Incorrect APN settings
- Damaged SIM card
Correct answer: Network congestion in the cell sector
Full signal bars with slow data typically indicate network congestion where many users share the same cell sector bandwidth.
Question 2: Which Wi-Fi frequency band offers the longest range but lowest throughput?
- 5 GHz
- 6 GHz
- 2.4 GHz (Correct answer)
- 60 GHz
Correct answer: 2.4 GHz
The 2.4 GHz band has better wall penetration and longer range than 5 GHz or 6 GHz, but offers lower maximum throughput.
Question 3: What does MIMO stand for in the context of wireless networking?
- Multiple Input Multiple Output (Correct answer)
- Mobile Internet Multi-Optimized
- Modulated Input Modulated Output
- Multi-Interface Mobile Operation
Correct answer: Multiple Input Multiple Output
MIMO (Multiple Input Multiple Output) uses multiple antennas to send and receive more data simultaneously, improving throughput and reliability.
Question 4: A technician replaces a phone's Wi-Fi antenna flex cable. After reassembly, the device connects to 2.4 GHz but not 5 GHz. What is the most likely issue?
- Wrong APN configured
- Only one antenna connected — 5 GHz requires dual-band antenna (Correct answer)
- Operating system needs update
- Router 5 GHz band is disabled
Correct answer: Only one antenna connected — 5 GHz requires dual-band antenna
Many phones use separate antenna paths for 2.4 GHz and 5 GHz; if the secondary antenna or its connector is missed during reassembly, 5 GHz fails.
Question 5: What is the primary purpose of an Access Point Name (APN) on a mobile device?
- Identifies the device's IMEI to the carrier
- Defines the gateway between the carrier network and the internet (Correct answer)
- Encrypts SMS messages end-to-end
- Controls Wi-Fi channel selection
Correct answer: Defines the gateway between the carrier network and the internet
The APN specifies the carrier's gateway settings that allow the device to connect to the correct data network and services.
Question 6: Which Bluetooth version introduced Low Energy (BLE) as a core feature?
- Bluetooth 2.1
- Bluetooth 3.0
- Bluetooth 4.0 (Correct answer)
- Bluetooth 5.0
Correct answer: Bluetooth 4.0
Bluetooth 4.0 introduced Bluetooth Low Energy (BLE), enabling long battery life for IoT and fitness devices.
Question 7: A phone fails to maintain a Bluetooth connection beyond 3 feet despite the paired device being within 30 feet. After ruling out software issues, what should the technician inspect?
- Battery capacity
- Bluetooth antenna and its coaxial connector (Correct answer)
- NFC chip
- Proximity sensor
Correct answer: Bluetooth antenna and its coaxial connector
Severely limited Bluetooth range is a classic symptom of a disconnected or damaged Bluetooth antenna or its coaxial snap connector inside the device.
CMT Network Technologies & Connectivity 2
A customer's phone shows full LTE bars but data speeds are extremely slow.
What is the most likely cause?