What is 4G Communication? | 3rd Generation Mobile Communication System with High-Speed Digital Communications | NEXTY Electronics, an Electronic Components and Semiconductor Trading Company

4G communication overview

4G communication was originally called LTE (short for Long Term Evolution) and was also called "3.9G." After 2010, two standards, LTE-Advanced and WirelessMAN-Advanced (WiMAX2), were formulated, and these were collectively referred to as "4G communication."

Differences between LTE and 4G communication

LTE is a communication standard developed during the transition from 3G to 4G communication, and is the previous generation standard for 4G communication.
4G communication is a general term for the fourth generation mobile communication system, and includes multiple communication standards including LTE.
Since the International Telecommunication Union (ITU) has recognized LTE and 4G communications as the same communications standard, fewer carriers are currently distinguishing between LTE and 4G.

4G communication compatible frequencies (Japan)

The frequency bands used for 4G communications in Japan are as follows:

frequency	700MHz band	800MHz band		900MHz band	1.5GHz帯		1.7GHz帯	2.0GHz帯	3.5GHz帯
Career	Band28	Band18,26	Band19	Band8	Band11	Band21	Band3	Band1	Band42
NTT Docomo	〇		〇			〇	〇	〇	〇
KDDI (AU)	〇	〇			〇		〇	〇	〇
SoftBank	〇			〇	〇		〇	〇	〇
Rakuten							〇

Transition from 4G to 5G

There are no plans to end 4G communication services as of February 2025, and it is likely that 5G and 4G communication will continue to operate in parallel for some time to come.

Typical technologies used in 4G communication

The main technologies used in 4G communication are as follows:
These technologies enable 4G communications to achieve high data speeds, low latency, and wide coverage.

OFDM (Orthogonal Frequency Division Multiplexing)

4G communications use OFDM technology, which splits data across multiple subcarriers and transmits them simultaneously, improving frequency utilization efficiency and resistance to multipath interference.

MIMO (Multiple Input Multiple Output)

MIMO technology stands for "Multi Input Multi Output" and improves communication speed and signal quality by using multiple ANTENNAS in the same frequency band to simultaneously send and receive data. It is also used in IEEE802.11n (WiFi4) and 2x2 and 4x4 MIMO configurations are commonly used in 4G communications.

Carrier Aggregation

4G communications (LTE-Advanced) employs carrier aggregation technology, which further improves communication speeds by simultaneously using multiple frequency bands.