Get the latest buzz about AP Telecom updates via SMS on your mobile phone for FREE. To subscribe, just send an SMS as ON aptelecom to +91-9870807070 or else click here

For any kind of further queries, feel free to call Vishaal on 9494-555-121

Mobile Network Technology

1G Network:

1G (or 1-G) refers to the first-generation of wireless telephone technology, mobile telecommunications. These are the analog telecommunications standards that were introduced in the 1980s and continued until being replaced by 2G digital telecommunications. The main difference between two succeeding mobile telephone systems, 1G and 2G, is that the radio signals that 1G networks use are analog, while 2G networks are digital.

Although both systems use digital signaling to connect the radio towers (which listen to the handsets) to the rest of the telephone system, the voice itself during a call is encoded to digital signals in 2G whereas 1G is only modulated to higher frequency, typically 150 MHz and up.

One such standard is NMT (Nordic Mobile Telephone), used in Nordic countries, Switzerland, Netherlands, Eastern Europe and Russia. Others include AMPS (Advanced Mobile Phone System) used in the United States and Australia, TACS (Total Access Communications System) in the United Kingdom, C-450 in West Germany, Portugal and South Africa, Radiocom 2000 in France, and RTMI in Italy. In Japan there were multiple systems. Three standards, TZ-801, TZ-802, and TZ-803 were developed by NTT, while a competing system operated by DDI used the JTACS (Japan Total Access Communications System) standard.Antecedent to 1G technology is the mobile radio telephone, or 0G.


2G Network:
2G (or 2-G) is short for second-generation wireless telephone technology. Second generation 2G cellular telecom networks were commercially launched on the GSM standard in Finland by Radiolinja (now part of Elisa Oyj) in 1991. Three primary benefits of 2G networks over their predecessors were that phone conversations were digitally encrypted; 2G systems were significantly more efficient on the spectrum allowing for far greater mobile phone penetration levels; and 2G introduced data services for mobile, starting with SMS text messages.

After 2G was launched, the previous mobile telephone systems were retrospectively dubbed 1G. While radio signals on 1G networks are analog, and on 2G networks are digital, both systems use digital signaling to connect the radio towers (which listen to the handsets) to the rest of the telephone system.
2G has been superseded by newer technologies such as 2.5G, 2.75G, 3G, and 4G; however, 2G networks are still used in many parts of the world.
  
2G Technologies:

2G technologies can be divided into TDMA-based and CDMA-based standards depending on the type of multiplexing used. The main 2G standards are:
  • GSM (TDMA-based), originally from Europe but used in almost all countries on all six inhabited continents (Time Division Multiple Access). Today accounts for over 80% of all subscribers around the world. Over 60 GSM operators are also using CDMA2000 in the 450 MHz frequency band (CDMA450).
  • IS-95 aka cdmaOne (CDMA-based, commonly referred as simply CDMA in the US), used in the Americas and parts of Asia. Today accounts for about 17% of all subscribers globally. Over a dozen CDMA operators have migrated to GSM including operators in Mexico, India, Australia and South Korea.
  • PDC (TDMA-based), used exclusively in Japan
  • iDEN (TDMA-based), proprietary network used by Nextel in the United States and Telus Mobility in Canada
  • IS-136 aka D-AMPS (TDMA-based, commonly referred as simply 'TDMA' in the US), was once prevalent in the Americas but most have migrated to GSM.
2G services are frequently referred as Personal Communications Service, or PCS, in the United States.

Capacities, advantages, and disadvantages:

Capacity:

Using digital signals between the handsets and the towers increases system capacity in two key ways:
  • Digital voice data can be compressed and multiplexed much more effectively than analog voice encodings through the use of various codecs, allowing more calls to be packed into the same amount of radio bandwidth.
  • The digital systems were designed to emit less radio power from the handsets. This meant that cells could be smaller, so more cells could be placed in the same amount of space. This was also made possible by cell towers and related equipment getting less expensive.

Advantages:

  • The lower power emissions helped address health concerns.
  • Going all-digital allowed for the introduction of digital data services, such as SMS and email.
  • Greatly reduced fraud. With analog systems it was possible to have two or more "cloned" handsets that had the same phone number.
  • Enhanced privacy. A key digital advantage not often mentioned is that digital cellular calls are much harder to eavesdrop on by use of radio scanners. While the security algorithms used have proved not to be as secure as initially advertised, 2G phones are immensely more private than 1G phones, which have no protection against eavesdropping.

Disadvantages:

  • In less populous areas, the weaker digital signal may not be sufficient to reach a cell tower. This tends to be a particular problem on 2G systems deployed on higher frequencies, but is mostly not a problem on 2G systems deployed on lower frequencies. National regulations differ greatly among countries which dictate where 2G can be deployed.
  • Analog has a smooth decay curve, digital a jagged steppy one. This can be both an advantage and a disadvantage. Under good conditions, digital will sound better. Under slightly worse conditions, analog will experience static, while digital has occasional dropouts. As conditions worsen, though, digital will start to completely fail, by dropping calls or being unintelligible, while analog slowly gets worse, generally holding a call longer and allowing at least a few words to get through.
  • While digital calls tend to be free of static and background noise, the lossy compression used by the codecs takes a toll; the range of sound that they convey is reduced. You'll hear less of the tonality of someone's voice talking on a digital cellphone, but you will hear it more clearly.

 

Evolution:

2G networks were built mainly for voice services and slow data transmission. Some protocols, such as EDGE for GSM and 1x-RTT for CDMA2000, are defined as "3G" services (because they are defined in IMT-2000 specification documents), but are considered by the general public to be 2.5G services (or 2.75G which sounds even more sophisticated) because they are several times slower than present-day 3G services.

2.5G (GPRS):

2.5G is a stepping stone between 2G and 3G cellular wireless technologies. 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. It does not necessarily provide faster services because bundling of timeslots is used for circuit switched data services (HSCSD) as well.

The first major step in the evolution of GSM networks to 3G occurred with the introduction of General Packet Radio Service (GPRS). CDMA2000 networks similarly evolved through the introduction of 1xRTT. The combination of these capabilities came to be known as 2.5G.

GPRS could provide data rates from 56 kbit/s up to 115 kbit/s. It can be used for services such as Wireless Application Protocol (WAP) access, Multimedia Messaging Service (MMS), and for Internet communication services such as email and World Wide Web access. GPRS data transfer is typically charged per megabyte of traffic transferred, while data communication via traditional circuit switching is billed per minute of connection time, independent of whether the user actually is utilizing the capacity or is in an idle state.

1xRTT supports bi-directional (up and downlink) peak data rates up to 153.6 kbit/s, delivering an average user data throughput of 80-100 kbit/s in commercial networks. It can also be used for WAP, SMS & MMS services, as well as Internet access.

2.75G (EDGE):

GPRS networks evolved to EDGE networks with the introduction of 8PSK encoding. Enhanced Data rates for GSM Evolution (EDGE), Enhanced GPRS (EGPRS), or IMT Single Carrier (IMT-SC) is a backward-compatible digital mobile phone technology that allows improved data transmission rates, as an extension on top of standard GSM. EDGE was deployed on GSM networks beginning in 2003--initially by Cingular (now AT&T) in the United States.

EDGE is standardized by 3GPP as part of the GSM family, and it is an upgrade that provides a potential three-fold increase in capacity of GSM/GPRS networks. The specification achieves higher data-rates (up to 236.8 k bit/s) by switching to more sophisticated methods of coding (8PSK), within existing GSM time slots.


3G Network:

International Mobile Telecommunications-2000 (IMT—2000), better known as 3G or 3rd Generation, is a generation of standards for mobile phones and mobile telecommunications services fulfilling specifications by the International Telecommunication Union.Application services include wide-area wireless voice telephone, mobile Internet access, video calls and mobile TV, all in a mobile environment. Compared to the older 2G and 2.5G standards, a 3G system must allow simultaneous use of speech and data services, and provide peak data rates of at least 200 kbit/s according to the IMT-2000 specification. Recent 3G releases, often denoted 3.5G and 3.75G, also provide mobile broadband access of several Mbit/s to laptop computers and smartphones.

The following standards are typically branded 3G:
  • The UMTS system, first offered in 2001, standardized by 3GPP, used primarily in Europe, Japan, China (however with a different radio interface) and other regions predominated by GSM 2G system infrastructure. The cell phones are typically UMTS and GSM hybrids. Several radio interfaces are offered, sharing the same infrastructure:
    • The original and most widespread radio interface is called W-CDMA.
    • The TD-SCDMA radio interface, was commercialized in 2009 and is only offered in China.
    • The latest UMTS release, HSPA+, can provide peak data rates up to 56 Mbit/s in the down link in theory (28 Mbit/s in existing services) and 22 Mbit/s in the up link.
  • The CDMA2000 system, first offered in 2002, standardized by 3GPP2, used especially in North America and South Korea, sharing infrastructure with the IS-95 2G standard. The cell phones are typically CDMA2000 and IS-95 hybrids. The latest release EVDO Rev B offers peak rates of 14.7 Mbit/s down streams.
The above systems and radio interfaces are based on kindred spread spectrum radio transmission technology. While the GSM EDGE standard ("2.9G"), DECT cordless phones and Mobile WiMAX standards formally also fulfill the IMT-2000 requirements and are approved as 3G standards by ITU, these are typically not branded 3G, and are based on completely different technologies.

A new generation of cellular standards has appeared approximately every tenth year since 1G systems were introduced in 1981/1982. Each generation is characterized by new frequency bands, higher data rates and non backwards compatible transmission technology. The first release of the 3GPP Long Term Evolution (LTE) standard does not completely fulfill the ITU 4G requirements called IMT-Advanced. First release LTE is not backwards compatible with 3G, but is a pre-4G or 3.9G technology, however sometimes branded "4G" by the service providers. WiMAX is another technology verging on or marketed as 4G.


Features:

Data rates

ITU has not provided a clear definition of the data rate users can expect from 3G equipment or providers. Thus users sold 3G service may not be able to point to a standard and say that the rates it specifies are not being met. While stating in commentary that "it is expected that IMT-2000 will provide higher transmission rates: a minimum data rate of 2 Mbit/s for stationary or walking users, and 384 kbit/s in a moving vehicle," the ITU does not actually clearly specify minimum or average rates or what modes of the interfaces qualify as 3G, so various rates are sold as 3G intended to meet customers expectations of broadband data.

Security

3G networks offer greater security than their 2G predecessors. By allowing the UE (User Equipment) to authenticate the network it is attaching to, the user can be sure the network is the intended one and not an impersonator. 3G networks use the KASUMI block crypto instead of the older A5/1 stream cipher. However, a number of serious weaknesses in the KASUMI cipher have been identified.In addition to the 3G network infrastructure security, end-to-end security is offered when application frameworks such as IMS are accessed, although this is not strictly a 3G property.

Applications

The bandwidth and location information available to 3G devices gives rise to applications not previously available to mobile phone users. Some of the applications are:
  • Mobile TV – a provider redirects a TV channel directly to the subscriber's phone where it can be watched.
  • Video on demand – a provider sends a movie to the subscriber's phone.
  • Video conferencing – subscribers can see as well as talk to each other.
  • Tele-medicine – a medical provider monitors or provides advice to the potentially isolated subscriber.
  • Location-based services – a provider sends localized weather or traffic conditions to the phone, or the phone allows the subscriber to find nearby businesses or friends..

Evolution:

Both 3GPP and 3GPP2 are currently working on extensions to 3G standard that are based on an all-IP network infrastructure and using advanced wireless technologies such as MIMO, these specifications already display features characteristic for IMT-Advanced (4G), the successor of 3G. However, falling short of the bandwidth requirements for 4G (which is 1 Gbit/s for stationary and 100 Mbit/s for mobile operation), these standards are classified as 3.9G or Pre-4G.

3GPP plans to meet the 4G goals with LTE Advanced, whereas Qualcomm has halted development of UMB in favor of the LTE family.

4G Network:

In telephony, 4G is the fourth generation of cellular wireless standards. It is a successor to 3G and 2G families of standards. A 4G system is expected to provide a comprehensive and secure all-IP based solution where facilities such as ultra-broadband (giga-bit speed such as 100+ MiB/s) Internet access, IP telephony, gaming services, and streamed multimedia may be provided to users.

Pre-4G technologies such as mobile WiMAX and first-release 3G Long term evolution (LTE) have been available on the market since 2006 and 2009 respectively, and are often branded as 4G. Current versions of these technologies do not fulfill the ITU-R requirements of data rates approximately up to 1 Gbit/s for 4G systems.

In all suggestions for 4G, the CDMA spread spectrum radio technology used in 3G systems and IS-95 is abandoned and replaced by frequency-domain equalization schemes, for example multi-carrier transmission such as OFDMA. This is combined with MIMO (Multiple In Multiple Out), e.g., multiple antennas, dynamic channel allocation and channel-dependent scheduling.

Background:

The nomenclature of the generations generally refers to a change in the fundamental nature of the service, non-backwards compatible transmission technology, and new frequency bands. The first was the move from 1981 analog (1G) to digital (2G) transmission in 1992. This was followed, in 2002, by 3G multi-media support, spread spectrum transmission and at least 200 kbit/s, soon expected to be followed by 4G, which refers to all-IP packet-switched networks, mobile ultra-broadband (gigabit speed) access and multi-carrier transmission.

Requirements:

This article uses 4G to refer to IMT-Advanced (International Mobile Telecommunications Advanced), as defined by ITU-R.

An IMT-Advanced cellular system must have target peak data rates of up to approximately 100 Mbit/s for high mobility such as mobile access and up to approximately 1 Gbit/s for low mobility such as nomadic/local wireless access, according to the ITU requirements. Scalable bandwidths up to at least 40 MHz should be provided.

4G Predecessors and candidate systems:

3GPP Long Term Evolution (LTE)


Telia-branded Samsung LTE modem

The pre-4G technology 3GPP Long Term Evolution (LTE) is often branded "4G", but the first LTE release does not fully comply with the IMT-Advanced requirements. LTE has a theoretical net bit rate capacity of up to 100 Mbit/s in the downlink and 50 Mbit/s in the uplink if a 20 MHz channel is used — and more if multiple-input multiple-output (MIMO), i.e. antenna arrays, are used.

The world's first publicly available LTE-service was opened in the two Scandinavian capitals Stockholm (Ericsson system) and Oslo (a Huawei system) on 14 December 2009, and branded 4G. The user terminals were manufactured by Samsung.The two largest major mobile carriers in the United States and several worldwide carriers have announced plans to convert their networks to LTE beginning in 2011.

The physical radio interface was at an early stage named High Speed OFDM Packet Access (HSOPA), now named Evolved UMTS Terrestrial Radio Access (E-UTRA).

The first LTE USB dongles do not support any other radio interface.

LTE Advanced

LTE Advanced (Long-term-evolution Advanced) is a candidate for IMT-Advanced standard, formally submitted by the 3GPP organization to ITU-T in the fall 2009, and expected to be released in 2012. The target of 3GPP LTE Advanced is to reach and surpass the ITU requirements. LTE Advanced should be compatible with first release LTE equipment, and should share frequency bands with first release LTE.

Mobile WiMAX (IEEE 802.16e)

The Mobile WiMAX (IEEE 802.16e-2005) mobile wireless broadband access (MWBA) standard (also known as WiBro in South Korea) is sometimes branded 4G, and offers peak data rates of 128 Mbit/s downlink and 56 Mbit/s uplink over 20 MHz wide channels.

The world's first commercial mobile WiMAX service was opened by KT in Seoul, South Korea on 30 June 2006

Sprint Nextel has begun using Mobile WiMAX, as of September 29, 2008 branded as a "4G" network even though current version does not fulfill the IMT Advanced requirements on 4G systems.

IEEE 802.16m:

The IEEE 802.16m evolution of 802.16e is under development, with the objective to fulfill the IMT-Advanced criteria of 1 Gbit/s for stationary reception and 100 Mbit/s for mobile reception.

UMB (formerly EV-DO Rev. C):

UMB (Ultra Mobile Broadband) was the brand name for a discontinued 4G project within the 3GPP2 standardization group to improve the CDMA2000 mobile phone standard for next generation applications and requirements. In November 2008, Qualcomm, UMB's lead sponsor, announced it was ending development of the technology, favouring LTE instead.The objective was to achieve data speeds over 275 Mbit/s downstream and over 75 Mbit/s upstream.

Flash-OFDM:

At an early stage the Flash-OFDM system was expected to be further developed into a 4G standard.

iBurst and MBWA (IEEE 802.20) systems

The iBurst system ( or HC-SDMA, High Capacity Spatial Division Multiple Access) was at an early stage considered as a 4G predecessor. It was later further developed into the Mobile Broadband Wireless Access (MBWA) system, also known as IEEE 802.20.

Objective and Approach:

Objectives:

4G is being developed to accommodate the quality of service (QoS) and rate requirements set by further development of existing 3G applications like mobile broadband access, Multimedia Messaging Service (MMS), video chat, mobile TV, but also new services like HDTV. 4G may allow roaming with wireless local area networks, and may interact with digital video broadcasting systems.
The 4G working group has defined the following as objectives of the 4G wireless communication standard:
  • Flexible channel bandwidth, between 5 and 20 MHz, optionally up to 40 MHz
  • A nominal data rate of 100 Mbit/s while the client physically moves at high speeds relative to the station, and 1 Gbit/s while client and station are in relatively fixed positions as defined by the ITU-R
  • A data rate of at least 100 Mbit/s between any two points in the world,
  • Peak link spectral efficiency of 15 bit/s/Hz in the downlink, and 6.75 bit/s/Hz in the uplink (meaning that 1 Gbit/s in the downlink should be possible over less than 67 MHz bandwidth)
  • System spectral efficiency of up to 3 bit/s/Hz/cell in the downlink and 2.25 bit/s/Hz/cell for indoor usage.
  • Smooth handoff across heterogeneous networks,
  • Seamless connectivity and global roaming across multiple networks,
  • High quality of service for next generation multimedia support (real time audio, high speed data, HDTV video content, mobile TV, etc.)
  • Interoperability with existing wireless standards,
  • An all IP, packet switched network.
  • Femtocells (home nodes connected to fixed Internet broadband infrastructure)

Approaches:

Consideration points

  • Coverage, radio environment, spectrum, services, business models and deployment types, users.

Principal technologies

  • Physical layer transmission techniques
    • MIMO: To attain ultra high spectral efficiency by means of spatial processing including multi-antenna and multi-user MIMO
    • Frequency-domain-equalization, for example Multi-carrier modulation (OFDM) or single-carrier frequency-domain-equalization (SC-FDE) in the downlink: To exploit the frequency selective channel property without complex equalization.
    • Frequency-domain statistical multiplexing, for example (OFDMA) or (Single-carrier FDMA) (SC-FDMA, a.k.a. Linearly precoded OFDMA, LP-OFDMA) in the uplink: Variable bit rate by assigning different sub-channels to different users based on the channel conditions
    • Turbo principle error-correcting codes: To minimize the required SNR at the reception side
  • Channel-dependent scheduling: To utilize the time-varying channel.
  • Link adaptation: Adaptive modulation and error-correcting codes
  • Relaying, including fixed relay networks (FRNs), and the cooperative relaying concept, known as multi-mode protocol

4G Features:

The 4G system was originally envisioned by the Defense Advanced Research Projects Agency (DARPA). The DARPA selected the distributed architecture, end-to-end Internet protocol (IP), and believed at an early stage in peer-to-peer networking in which every mobile device would be both a transceiver and a router for other devices in the network eliminating the spoke-and-hub weakness of 2G and 3G cellular systems.Since the 2.5G GPRS system, cellular systems have provided dual infrastructures: packet switched nodes for data services, and circuit switched nodes for voice calls. In 4G systems, the circuit-switched infrastructure is abandoned, and only a packet-switched network is provided. This means that traditional voice calls are replaced by IP telephony.

Cellular systems such as 4G allow seamless mobility; thus a file transfer is not interrupted in case a terminal moves from one call (one base station coverage area) to another, but handover is carried out. The terminal also keeps the same IP address while moving, meaning that a mobile server is reachable as long as it is within the coverage area of any server. In 4G systems this mobility is provided by the mobile IP protocol, part of IP version 6, while in earlier cellular generations it was only provided by physical layer and datalink layer protocols. In addition to seamless mobility, 4G provides flexible interoperability of the various kinds of existing wirelss networks, such as satellite, cellular wirelss, WLAN, PAN and systems for acessing fixed wireless networks.

While maintaining seamless mobility, 4G will offer very high data rates with expectations of 100Mbps wireless service. The increased bandwidth and higher data transmission rates will allow 4G users the ability to utilize high definition video and the video conferencing features of mobile devices attached to a 4G network. The 4G wireless system is expected to provide a comprehensive IP solution where multimedia applications and services can be delivered to the user on an ‘Anytime, Anywhere' basis with a satisfactory high data rate, premium quality and high security.

4G is described as MAGIC — Mobile multimedia, Anytime anywhere, Global mobility support, Integrated wireless solution, and Customized personal service

Some key features (primarily from users' points of view) of 4G mobile networks are as follows:
  • High usability: anytime, anywhere, and with any technology
  • Support for multimedia services at low transmission cost
  • Personalization
  • Integrated services
Some candidate systems suggest having an open Internet platform.

Components:

Access schemes:

As the wireless standards evolved, the access techniques used also exhibited increase in efficiency, capacity and scalability. The first generation wireless standards used plain TDMA and FDMA. In the wireless channels, TDMA proved to be less efficient in handling the high data rate channels as it requires large guard periods to alleviate the multipath impact. Similarly, FDMA consumed more bandwidth for guard to avoid inter carrier interference. So in second generation systems, one set of standard used the combination of FDMA and TDMA and the other set introduced an access scheme called CDMA. Usage of CDMA increased the system capacity, but as a theoretical drawback placed a soft limit on it rather than the hard limit (i.e. a CDMA network setup does not inherently reject new clients when it approaches its limits, resulting in a denial of service to all clients when the network overloads; though this outcome is avoided in practical implementations by admission control of circuit switched or fixed bitrate communication services). Data rate is also increased as this access scheme (providing the network is not reaching its capacity) is efficient enough to handle the multipath channel. This enabled the third generation systems, such as IS-2000, UMTS, HSXPA, 1xEV-DO, TD-CDMA and TD-SCDMA, to use CDMA as the access scheme. However, the issue with CDMA is that it suffers from poor spectral flexibility and computationally intensive time-domain equalization (high number of multiplications per second) for wideband channels.

Recently, new access schemes like Orthogonal FDMA (OFDMA), Single Carrier FDMA (SC-FDMA), Interleaved FDMA and Multi-carrier CDMA (MC-CDMA) are gaining more importance for the next generation systems. These are based on efficient FFT algorithms and frequency domain equalization, resulting in a lower number of multiplications per second. They also make it possible to control the bandwidth and form the spectrum in a flexible way. However, they require advanced dynamic channel allocation and traffic adaptive scheduling.

WiMax is using OFDMA in the downlink and in the uplink. For the next generation UMTS, OFDMA is used for the downlink. By contrast, IFDMA is being considered for the uplink since OFDMA contributes more to the PAPR related issues and results in nonlinear operation of amplifiers. IFDMA provides less power fluctuation and thus avoids amplifier issues. Similarly, MC-CDMA is in the proposal for the IEEE 802.20 standard. These access schemes offer the same efficiencies as older technologies like CDMA. Apart from this, scalability and higher data rates can be achieved.

The other important advantage of the above mentioned access techniques is that they require less complexity for equalization at the receiver. This is an added advantage especially in the MIMO environments since the spatial multiplexing transmission of MIMO systems inherently requires high complexity equalization at the receiver.

In addition to improvements in these multiplexing systems, improved modulation techniques are being used. Whereas earlier standards largely used Phase-shift keying, more efficient systems such as 64QAM are being proposed for use with the 3GPP Long Term Evolution standards.

IPv6 support:

Unlike 3G, which is based on two parallel infrastructures consisting of circuit switched and packet switched network nodes respectively, 4G will be based on packet switching only. This will require low-latency data transmission.
By the time that 4G is deployed, the process of IPv4 address exhaustion is expected to be in its final stages. Therefore, in the context of 4G, IPv6 support is essential in order to support a large number of wireless-enabled devices. By increasing the number of IP addresses, IPv6 removes the need for network address translation (NAT), a method of sharing a limited number of addresses among a larger group of devices, although NAT will still be required to communicate with devices that are on existing IPv4 networks.

Advanced antenna systems:

The performance of radio communications depends on an antenna system, termed smart or intelligent antenna. Recently, multiple antenna technologies are emerging to achieve the goal of 4G systems such as high rate, high reliability, and long range communications. In the early 1990s, to cater for the growing data rate needs of data communication, many transmission schemes were proposed. One technology, spatial multiplexing, gained importance for its bandwidth conservation and power efficiency. Spatial multiplexing involves deploying multiple antennas at the transmitter and at the receiver. Independent streams can then be transmitted simultaneously from all the antennas. This technology, called MIMO (as a branch of intelligent antenna), multiplies the base data rate by (the smaller of) the number of transmit antennas or the number of receive antennas. Apart from this, the reliability in transmitting high speed data in the fading channel can be improved by using more antennas at the transmitter or at the receiver. This is called transmit or receive diversity. Both transmit/receive diversity and transmit spatial multiplexing are categorized into the space-time coding techniques, which does not necessarily require the channel knowledge at the transmitter. The other category is closed-loop multiple antenna technologies, which require channel knowledge at the transmitter.

Software-defined radio (SDR):

SDR is one form of open wireless architecture (OWA). Since 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 technology, which is categorized to the area of the radio convergence.

4G Mobile technology - The mobile race to innovate, includes the following innovations: 

The mobile communications comprise two steps: access to the mobile network, and access to the mobile services. Traditionally, these two steps are all controlled by one operator in a closed and proprietary way. In the 4G mobile era, the access to the mobile services will be evolved to an open Mobile Cloud so that it is fully open to any developers and providers. In this way, any non-wireless industries, such as Google, Microsoft, Oracle, SAP, GM, Bank of America can provide services for their mobile users. The access to the mobile network is still controlled by the traditional wireless operators such as AT&T, Verizon,  T-Mobile and China Mobile. Of course, the operators are very reluctant to go this trend, but for the mobile users and for the future global movement, it is just a matter of time to do it. 

The mobile device system architecture will be open in order to converge multiple RTTs (radio transmission technologies) in one same device. Same as laptop computer, the future Smartphone will be based on open wireless architecture (OWA) technology which means, when you change the wireless standards, you do not need to change phone. It is totally different from current multi-standards phone which is in closed system architecture, and users can not remove the unused RTT modules and basically can not do anything on the mobile phone system. In the OWA system, you can just change RTT card in your Smartphone to switch your wireless standards, or you can integrate multiple wireless standards in one RTT SIM card. Based on this OWA platform, you can integrate home phone, office phone and mobile phone into one common Personal device - it is more beyond just a phone. In fact, this 4G mobile device is a system to bring the world to your hand, or we call it iHand - the World in Hand, which is more better than calling it an iPhone.
  1. Any portable consumer electronics device can be a mobile phone by inserting the OWA-powered mobile RTT(s) card. This approach is truly converging the mobile wireless technology with the computer technology by providing the OWA virtualization layer between the high-layer computer-based OS (operating systems) & applications solutions and the underlying wireless transmission-based different mobile networks access means.
  2. More breakthrough technologies are being developed for efficient utilization of wireless spectrum, and the dynamic and open spectrum management. Wireless is totally different from wired communications, and therefore the overall performance relies on both system performance and transmission performance where spectrum is one of the key issues.
  3. Power efficiency is another critical issue for mobile device. The system architecture must be open to enable removable of unused modules, and the processing architecture must be optimized to the lowest possible in terms of the whole system performance. Meanwhile, the RF radio modules should be narrowed to the minimal meeting the basic requirements of necessary RTTs.
The world is moving rapidly towards this 4G open mobile movement. In China, the government has in fact,  targeted for 4G mobile industry. In European Union, evolution to 4G has been the mission-critical strategy since 2003. Japan and Korea started 4G regulations in 2002. The US mobile market is a pretty different case, because FCC as a law enforcement agency, basically has no power to enforce law. The operators pay huge to the congress, and congress manages the FCC. So eventually, the operator "makes" the law. However, nobody can stop future and it is just a matter of time when this 4G open mobile comes to life.

5G Network:

5G (5th generation mobile networks or 5th generation wireless systems) is a name used in some research papers and projects to denote the next major phase of mobile telecommunications standards beyond the upcoming 4G standards (expected to be finalized between approximately 2011 and 2013). Currently, 5G is not a term officially used for any particular specification or in any official document yet made public by telecommunication companies or standardization bodies such as 3GPP, WiMAX Forum or ITU-R. New 3GPP standard releases beyond 4G and LTE Advanced are in progress, but not considered as new mobile generations.

Prognoses:

The implementation of standards under a 5G umbrella would likely be around the year of 2020.A new mobile generation has appeared every 10th year since the first 1G system (NMT) was introduced in 1981, including the 2G (GSM) system that started to roll out in 1992, and 3G (W-CDMA/FOMA) which appeared in 2001. The development of the 2G (GSM) and 3G (IMT-2000 and UMTS) standards took about 10 years from the official start of the R&D projects, and development of 4G systems started in 2001 or 2002.

It is expected that in terms of data streams, a 5G standard would have peak download and upload speeds of more than 1 Gbps.The development of the bit rates offered by cellular systems is however hard to predict, since the historical bit rate development has shown very little resemblance with a simple exponential function of time (as opposed to for example Moore's law for computing capacity). The data rate increased by a factor 8 from 1G (NMT 1.2 kbps) to 2G (GSM 9.6 kbps). The peak bit rate increased by a factor 40 from 2G to 3G for mobile users (384 kbps), and by a factor of 200 from 2G to 3G for stationary users (2 Mbps). The peak bit rates are expected to increase by a factor 260 from 3G to 4G for mobile users (100 Mbps) and by a factor 500 from 4G to 5G for stationary users (1 Gbps).

Research:

Key concepts suggested in research papers discussing 5G and beyond 4G wireless communications are:
  • Real wireless world with no more limitation with access and zone issues.
  • Wearable devices with AI capabilities. 
  • Internet protocol version 6 (IPv6), where a visiting care-of mobile IP address is assigned according to location and connected network.
  • One unified global standard.
  • Pervasive networks providing ubiquitous computing: The user can simultaneously be connected to several wireless access technologies and seamlessly move between them.These access technologies can be a 2.5G, 3G, 4G or 5G mobile networks, Wi-Fi, WPAN or any other future access technology. In 5G, the concept may be further developed into multiple concurrent data transfer paths.
  • Cognitive radio technology, also known as smart-radio: allowing different radio technologies to share the same spectrum efficiently by adaptively finding unused spectrum and adapting the transmission scheme to the requirements of the technologies currently sharing the spectrum. This dynamic radio resource management is achieved in a distributed fashion, and relies on software defined radio.
  • High altitude stratospheric platform station (HAPS) systems.
The radio interface of 5G communication systems is suggested in a Korean research and development program to be based on beam division multiple access (BDMA) and group cooperative relay techniques.

5G Networks provides its own suite of specialized connectivity solutions to deliver "Plug and Play" high speed Internet access to end-users in hotels, apartments, office buildings and other high density environments.

5G's Last Yard Connectivity(TM) solutions operate over existing telephone wiring as well as high quality data and fiber-optic cable and wireless. 5G Networks bridges the gap between the carrier's broadband fiber-optic network and the user's desktop.

5G Networks has developed Speed Test(TM), which is a tool to help you measure and determine your true Internet network connection speed and data throughput. Speed Test(TM) is the simplest and most accurate performance measurement tool available on the market.