4G Wireless Networks
INTRODUCTION
4G stands for “4th generation” mobile data protocol but 4G users called it as the speed, succeeding 3G and preceding 5G. 4G LTE is a term used for the particular 4G protocol that delivers the fastest mobile Internet experience. A 4G LTE network operates at the leading edge of speed and reliability. Potential and current applications include amended mobile web access, IP telephony, gaming services, high-definition mobile TV, video conferencing, 3D television, and cloud computing. 4G networks are becoming pretty standard, so most of the newest and most cutting-edge phones (Samsung Galaxy S3, iPhone 5, etc.) are typically 4G phones.
4G network can download files from the Internet up to 10 times faster than with 3G. With 4G LTE, using the web from phone becomes as pleasurable as using it from computer.
3G is “3rd generation,” refers to a networking standard in cell phone technology that is capable of providing high-speed data service to mobile devices. 3G wireless networks became more widespread and made smartphones truly feasible however phones were used merely for voice calls and text messaging. A world where it’s perfectly ordinary to download huge data to the phone from the Internet, to stream audio and video to people thousands of miles away effortlessly and wirelessly. It changed the way millions of people communicate, and set the stage for even more advanced mobile technologies.
3G telecommunication networks support services that provide an information transfer rate of at least 200 Kbit/s also known as 3.5G and 3.75G, and provide mobile broadband access of several Mbit/s to smartphones and mobile modems in laptop computers. It can be applied to wireless voice telephony, mobile Internet access, fixed wireless Internet access, video calls and mobile TV technologies.
The first 3G networks were introduced in 1998 and fourth generation "4G" networks in 2008. 1G systems were introduced in 1981/1982 and each generation is characterized by new frequency bands, higher data rates and non–backward-compatible transmission technology.
The fastest 3G-based standard in the UMTS family is the HSPA+ standard, which is commercially available since 2009 and offers 28 Mbit/s downstream (22 Mbit/s upstream) without MIMO, i.e. only with one antenna, and in 2011 accelerated up to 42 Mbit/s peak bit rate downstream using either DC-HSPA+ (simultaneous use of two 5 MHz UMTS carriers) or 2x2 MIMO. The fastest 3G-based standard in the CDMA2000 family is the EV-DO Rev. B, which is available since 2010 and offers 15.67 Mbit/s downstream. A 3G phone cannot communicate through a 4G network, but newer generations of phones are usually designed to be backward compatible, so a 4G phone can communicate through a 3G or even 2G network.

4G is much faster than 3G. 4G is good in surfing the Web and especially stream video and connecting a laptop to mobile link, 4G involves transferring large amounts of data with a big boost. If you have a 3G phone and you've been frustrated with slow data, 4G may be the solution. 4G won't solve any dropped call problems, though, as all calls will be made over older networks until carriers switch to voice-over-LTE during the next few years.
The Mobile WiMAX mobile wireless broadband access (MWBA) standard is sometimes branded 4G, and offers peak data rates of 128 Mbit/s downlink and 56 Mbit/s uplink over 20 MHz wide channels.
4G is a collection of wireless standards, the final form of a 4G device will constitute various standards. This can be efficiently realized using SDR (Software defined-radio) technology, which is categorized to the area of the radio convergence. Verizon Wireless, AT&T, T-Mobile and Sprint Corporation all use 4G LTE. Only Sprint still utilizes WiMAX, but plans to end its use of WiMAX by 2015.
All types of wireless networking seems confusing, however there are some difference between the wireless standards known as Wi-Fi, WiMAX, and WiBro. Each one is similar in that each provides a way to connect to a wireless network for workstation communication or Internet access. Each technology may be seen as an improvement from the previous one as well. WiBro, which stands for Wireless Broadband, is very similar to WiMAX. The transmission speeds are much the same, but the main difference is that WiBro can track a receiver that is moving from place to place. It may also be called mobile WiMAX but not truly mobile as it can be used effectively while the receiver is moving at high rates of speed. However, it means the receiver can move from place to place and experience no degradation in service, as long as the receiver stays within range. WiMAX does not offer this because it needs a stationary antenna in order to receive a signal.
WiBro is that it is still under development as it improves, the receivers will be able to maintain connections even while traveling at high rates of speed. In those cases, it may call for a completely different standard altogether with a completely different name.