Multiple Access Scheme: Primarily based on CDMA (Code Division Multiple Access) or WCDMA (Wideband Code Division Multiple Access) for simultaneous data transmission.
Data Transfer Speeds: Initially targeted at 200 kbps to 2 Mbps for mobile devices.
Frequency Bands: Operates in various frequency bands, including the 2.1 GHz band.
Core Network: Utilizes circuit-switched and packet-switched networks for voice and data transmission.
Services: Provided mobile broadband internet, video calling, and higher data rates compared to 2G.
b. Key Features:
High Data Rates: 3G provided significantly higher data rates, enabling faster internet access and multimedia services.
Mobile Broadband: Enabled a wide range of mobile internet services beyond simple voice communication.
Global Roaming: Standardized protocols allowed for global roaming capabilities.
2. LTE (Long-Term Evolution):
a. Technology:
Multiple Access Scheme: Primarily uses OFDMA (Orthogonal Frequency Division Multiple Access) for downlink and SC-FDMA (Single Carrier Frequency Division Multiple Access) for uplink.
Data Transfer Speeds: Provides peak data rates up to several hundred Mbps for mobile devices.
Frequency Bands: Operates in various frequency bands, including both paired (FDD) and unpaired (TDD) spectrum.
Core Network: Evolved Packet Core (EPC) architecture, a simplified and optimized packet-switched network.
Services: Supports high-quality video streaming, online gaming, and other data-intensive applications.
b. Key Features:
Low Latency: Reduced latency compared to 3G, crucial for real-time applications like online gaming and video conferencing.
Spectrum Efficiency: Efficiently utilizes the available spectrum with advanced modulation and coding techniques.
Backward Compatibility: LTE networks can coexist with 2G and 3G networks, providing backward compatibility.
3. 5G (Fifth Generation):
a. Technology:
Multiple Access Scheme: Utilizes OFDMA for downlink and SC-FDMA for uplink, similar to LTE.
Data Transfer Speeds: Aims to provide peak data rates in the order of several Gbps for mobile devices.
Frequency Bands: Operates in both sub-6 GHz and millimeter-wave (mmWave) frequency bands.
Core Network: Introduces a new core network architecture called 5G Core (5GC).
Services: Enables ultra-reliable low-latency communication (URLLC), massive machine-type communication (mMTC), and enhanced mobile broadband (eMBB).
b. Key Features:
Low Latency: 5G targets extremely low latency, making it suitable for applications like autonomous vehicles and industrial automation.
Massive Connectivity: Designed to connect a vast number of devices simultaneously, supporting the Internet of Things (IoT).
Beamforming and MIMO: Utilizes advanced antenna technologies like massive MIMO (Multiple Input Multiple Output) and beamforming to enhance coverage and capacity.
Network Slicing: Allows network operators to create virtual networks tailored to specific use cases.
