4G technology is a descendant of 2G and 3G that aims to provide high speed data transfer. Among the latest technologies and gadgets, 4G, or fourth generation, gadgets are rocking the digital world. Through this technology, you will be provided speedy wireless internet access not only if you are a stationary user, but also if you are a mobile user. The 4G technology is expected to fulfill the deficiencies of 3G technology in terms to quality and speed. Most digital experts are expressing the 4G technology using the word ‘MAGIC’. Through 4G technology, you will be able to access mobile multimedia anytime, anywhere throughout the globe.
Evolution of Mobile Technologies
Zero Generation Technology (0G)
0G refers to pre-cell phone mobile telephony. Being the predecessors of the first generation of cellular telephones, these systems are called 0G (zero generation) systems. Usually vehicle mounted, they had the transceivers mounted in the vehicle trunk and dials and display mounted near the driver seat. Technologies used in 0G systems included PTT (Push to Talk), MTS (Mobile Telephone System), IMTS (Improved Mobile Telephone Service), and AMTS (Advanced Mobile Telephone System).
First Generation Technology (1G)
1G refers to the first generation of wireless telecommunication technology, more popularly known as cell phones. In 1G, a narrow band analogue wireless network is used; with this, we can have the voice calls. These services are provided with circuit switching. Through 1G, a voice call gets modulated to a higher frequency of about 150MHz and up as it is transmitted between radio towers using a technique called Frequency-Division Multiple Access (FDMA).
Different 1G standards that were prevalent were AMPS (Advanced Mobile Phone System) in the United States, TACS (Total Access Communications System) in the United Kingdom, and NMT (Nordic Mobile Telephone), used in Nordic countries, Eastern Europe, and Russia.
Second Generation Technology
2G first appeared around the late 1980’s; 2G system digitized the voice signal as well as the control link. It provided the facility of short message service (SMS), unlike 1G that had its prime focus on verbal communication. Depending on the type of multiplexing used, 2G technologies can be divided into Time Division Multiple Access (TDMA) based and Code Division Multiple Access (CDMA). 2G systems offered better quality and much more capacity. 2G cell phone units were generally smaller than 1G units since they emitted less radio power. .
Based on TDMA, Global System for Mobile communications (GSM) was the first European standard and the first commercial network for use by the public for 2nd generation mobile (2G) telephony. A typical 2G G.S.M network service uses 800/900MHz or 1800/1900 frequency spectrum. The typical average data rate of GSM is 9.6 kbps. 2G CDMA (IS-95A) uses BPSK and offers data rate upto 14.4 kbps. The bandwidth of 2G is 30-200 KHz.
2.5G – GPRS (General Packet Radio Service) – 2.5G, which stands for “second and a half generation,” is a cellular wireless technology developed in between its predecessor, 2G, and its successor, 3G. The term “second and a half generation” is used to describe 2G-systems that have implemented a packet switched domain in addition to the circuit switched domain. GPRS (CS1 to CS4) uses GMSK modulation with a symbol rate (and modulation rate) of 270 ksym/s. The typical data rate of GPRS is about115 kbps. It can be used for services such as Wireless Application Protocol (WAP) access, Multimedia Messaging Service (MMS), and for accessing internet. IS-95B, or cdmaOne, is the evolved version of IS-95A and is also designated as 2.5G with theoretical data rates of up to 115 kbps with generally experienced rates of 64 kbps.
2.75 – EDGE (Enhanced Data rates for GSM Evolution) – EDGE (EGPRS) is an abbreviation for Enhanced Data rates for GSM Evolution, and it is a digital mobile phone technology invented by AT&T.
EDGE technology is an extended version of GSM, and it works in GSM networks. EDGE is added on to GPRS and can function on any network with GPRS deployed on it, provided that the carrier implements the necessary upgrades. It allows the clear and fast transmission of data. One need not install any additional hardware and software in order to make use of EDGE technology. Also, there are no additional charges for utilizing this technology. EDGE uses 9 modulation coding schemes (MCS1-9). MCS (1-4) uses GMSK, while MCS (5-9) uses 8PSK modulation. 8PSK increases throughput by 3x (8-PSK – 3 bits/symbol vs GMSK 1 bit/symbol). The modulation bit rate is 810 kbps, and it offers data rates of 384kbps, theoretically up to 473.6kbps
Third Generation Technology (3G)
3G systems promise faster communications services entailing voice, fax, and Internet data transfer capabilities. The aim of 3G is to provide these services anytime, anywhere throughout the globe with seamless roaming between standards. ITU’s IMT-2000 is a global standard for 3G. 3G networks are wide-area cellular telephone networks, which have evolved to incorporate high-speed internet access and video telephony. It offers large capacity and broadband capabilities. It has greater network capacity through improved spectrum efficiency. 3G technology supports around 144 Kbps with high speed movement (i.e. in a vehicle), 384 Kbps locally, and up to 2Mbps for fixed stations (i.e. in a building). 3G technology uses CDMA, TDMA, and FDMA. The data are sent through packet switching. Voice calls are interpreted through circuit switching. It is a highly sophisticated form of communication that has come up in the last decade.
3G has the following enhancements over 2.5G and previous networks:
· Enhanced audio and video streaming;
· Several Times higher data speed;
· Video-conferencing support;
· Web and WAP browsing at higher speeds;
· IPTV (TV through the Internet) support; and
· Global roaming.
There are many 3G technologies such as W-CDMA, CDMA2000, UMTS, DECT, and WiMAX.
3.5G – HSDPA (High-Speed Downlink Packet Access)
High-Speed Downlink Packet Access (HSDPA) is a mobile telephony protocol, also called 3.5G. It is an enhanced version and the next intermediate generation of 3G UMTS, allowing for higher data transfer speeds.
HSDPA is a packet-based data service in W-CDMA downlink with data transmission up to 8-10 Mbps (and 20 Mbps for MIMO systems) over a 5MHz bandwidth in WCDMA downlink. This high data rate is enabled by use of adaptive modulation can coding (AMC), hybrid automatic repeat-request (HARQ), and fast packet scheduling at the access point.
3.75G – HSUPA (High-Speed Uplink Packet Access)
High Speed Uplink Packet Access (HSUPA) is a UMTS /WCDMA uplink evolution technology. The HSUPA mobile telecommunications technology is directly related to HSDPA and the two are complimentary to one another.
· 3G may not be sufficient to meet the needs of future high-performance applications like multi-media, full-motion video, and wireless teleconferencing.
· Multiple standards for 3G make it difficult to roam and to interoperate across networks.
· Requirement of a single broadband network with high data rates, which integrates wireless LANs, Bluetooth, cellular networks, and so on.
Also known as “Beyond 3G”, 4G refers to the fourth generation of wireless communications. The deployment of 4G networks should be in the 2010-2015 timeframe and will enable another leap in wireless data-rate and spectral efficiency. ITU has specified IMT-A (IMT-Advanced) for 4G standards.
4G is all about convergence; convergence of wired and wireless networks, wireless technologies, including GSM, wireless LAN, and Bluetooth as well as computers, consumer electronics, communication technology, and several others. 4G is a mobile multimedia, anytime, anywhere, Global mobility support, integrated wireless solution, and customized personal service network system.
4G wireless technology is also referred to by “MAGIC,” which stands for Mobile multimedia, Any-where, Global mobility solutions over, integrated wireless and Customized services.
4G is an all IP-based integrated system that will be capable of providing 100 Mbps for high mobility and 1 Gbps for low mobility with end-to-end QoS and high security. It will offer various services at any time, as per user requirements, anywhere with seamless interoperability at affordable cost.
The user services include IP telephony, ultra-broadband Internet access, gaming services, and High Definition Television (HDTV) streamed multimedia.
4G Requirements – As per ITU’s IMT-A
· All-IP packet switched network
· Data rates up to 100 Mbps for high mobility and up to 1 Gbps for low mobility
· Seamless connectivity and global roaming
· Interoperability with existing wireless standards
· Smooth handovers
· High QoS
|Network Architecture||Cell-based||Integration of various wireless technologies|
|Speeds||384 Kbps to 2 Mbps||100 Mbps to 1 Gbps|
|Frequency Band||Dependent on country or continent (1800-2400 MHz)||Higher frequency bands (2-8 GHz)|
|Bandwidth||5-20 MHz||100 MHz (or more)|
|Switching Scheme||Circuit and packet||Packet|
|Access Technologies||W-CDMA, 1xRTT, Edge||OFDM and MC-CDMA|
|IP||Number of air link protocols||All IP (IP6.0)|
4-G Systems … WirelessMAN-Advanced
- IMT-A compliant version of WiMAX or WiMAX 2 based on IEEE 802.16m
- WiMAX (Worldwide Interoperability for Microwave Access) is an IP based, wireless broadband access technology
- WirelessMAN is under development
- Present implementation of WiMAX does not comply with 4G specifications
- Uses OFDM in uplink and downlink
- Mobile WiMAX IEEE 802.16e standard offers peak data rates of 128 Mbit/s downlink and 56 Mbit/s uplink over 20 MHz wide channel
- 4G LTE (Long Term Evolution) Advanced
- IMT-A complaint version of LTE, also referred to as E-UTRA (Evolved UMTS Terrestrial Radio Access), or E-UTRAN(Evolved UMTS Terrestrial Radio Access Network)
- UMTS Long Term Evolution (LTE) was introduced in 3GPP Release 8, which supports data rates of up to 300 Mbps (4×4 MIMO) and up to 150 Mbps (2×2 MIMO) in the downlink and up to 75 Mbps in the uplink. Release 10 of LTE is likely to approach IMT-A, download upto 1 Gbps, and upload upto 500 Mbps
- Uses OFDMA for downlink and uses Single Carrier Frequency Division Multiple Access (SC-FDMA) for uplink
- Uses 64QAM modulation
- Uses MIMO and beam forming with up to 4 antennas
- All IP Network
4G Wireless Technology – It Just Gets Better and Better
You see that all the major players in the wireless phone market are scrambling to introduce their coveted version of the wireless 4g phones. We will all reap the benefits of this tech war because when the dust settles, we will be able to stream our favorite video, game, or mp3 with ease.
Moving Beyond 4G
4G is not the end of all. “5G Technology” is already in that research arena and is bound to up the data rate further. 5G is going to alter the usage of our cell phones and may replace our desktop PCs/laptops. Coupled with innovations being done in the field of smart sensors, 5G mobile phones with extremely high data rates, IP core, and world-wide coverage will offer features which have not been imagined so far. Currently, 5G is not a term officially used for any particular specification; however, it is being used in research papers and standardization bodies for the future wireless standards.
4G in India
Reliance Industries (RIL) is gearing up to start rolling out 4G services in India as early as the beginning of this year and reach countrywide deployment by mid-2012, according to a report by The Economic Times. The Mukesh Ambani-headed company has acquired Infotel, which won the pan-India spectrum for broadband wireless access in 2010, and plans to capitalize on this newfound asset with a rapid rollout. Sources within the company revealed to The Economic Times that it plans to provide 4G connectivity to 700 cities by June next year.
Knowing that low cost and high speed is the key to success in this market, RIL will be touting speeds of up to 50 – 100 Mbps on its network, which are at least seven times faster than the current 3G speeds in India. It is also planning to launch low-cost data cards and Android-powered tablets, priced between ₹ 3,000 ($60) – ₹ 8,000 ($165), to capitalize on the price-sensitive market in India.
The company is supposed to already have completed a test run of networking equipment from Alcatel Lucent, Ericsson and Huawei and will be contracting either one or all three of the manufacturers for equipment supplies as it builds out the network. For tablets, it is looking at prototypes from over 15 Chinese and Taiwanese original equipment manufacturers (OEMs) and will be selecting a few of the designs to offer in India.
RIL is in talks with companies like Walt Disney, through its Indian arm UTV Software, to offer apps, games, media and other licensed content on its network. The deal with Disney, in particular, is “close to being finalized”, according to the publication’s sources.
Provided that all of this goes through smoothly, the only hurdle left to clear will be government regulations that currently prohibit the use of RIL’s wireless access spectrum for transmitting voice data. Although the company is currently planning the rollout of a data-only network, a change in government regulations may allow it to offer voice services on its 4G network in the future.
This article was written by Sagar Borhade, a member of the MRCC Java Team. Sagar has a degree in Electronics and Telecom Engineering.