📑 Contents

Question 39

With reference to Visible Light Communication (VLC) technology, which of the following statements are correct?
1. VLC uses electromagnetic spectrum wavelengths 375 to 780 nm.
2. VLC is known as long-range optical wireless communication.
3. VLC can transmit large amounts of data faster than Bluetooth.
4. VLC has no electromagnetic interference.
Select the correct answer using the code given below:

AOptions

A) 1, 2 and 3 only

B) 1, 2 and 4 only

C) 1, 3 and 4 only

D) 2, 3 and 4 only

BSolution

Let's analyze the statements regarding Visible Light Communication (VLC) technology:

1. VLC uses electromagnetic spectrum wavelengths 375 to 780 nm. This statement is correct. Visible Light Communication, as its name suggests, utilizes the visible light portion of the electromagnetic spectrum, which typically ranges from approximately 375 nanometers (violet) to 780 nanometers (red).

2. VLC is known as long-range optical wireless communication. This statement is incorrect. VLC is primarily considered a *short-range* communication technology. Its range is limited by line-of-sight requirements and the ability of light to penetrate obstacles, typically working within a room or a few meters. It is not designed for long-range communication like radio waves or microwaves.

3. VLC can transmit large amounts of data faster than Bluetooth. This statement is correct. VLC technologies, such as Li-Fi (Light Fidelity), are capable of achieving very high data transmission speeds, often significantly faster than conventional Wi-Fi and several orders of magnitude faster than Bluetooth, which operates at much lower data rates.

4. VLC has no electromagnetic interference. This statement is correct. Since VLC uses light waves for data transmission, it does not generate or suffer from electromagnetic interference (EMI). This makes it particularly suitable for environments sensitive to radio frequency interference, such as hospitals, aircraft cabins, or power plants, and can also offer enhanced security as light cannot pass through walls.

Based on this analysis, statements 1, 3, and 4 are correct.

CStrategy

For questions on emerging technologies, understand their fundamental principles, advantages, disadvantages, and typical application scenarios. Pay close attention to qualifiers like 'long-range' or 'short-range' and claims about interference or speed, as these are often distinguishing features.

DSyllabus Analysis

This question falls under Science & Technology, specifically focusing on Communication Technologies and their underlying principles.

EQuestion Analysis

Medium to Difficult. Requires specific technical details about a relatively niche communication technology, especially concerning its range and interference properties.