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  • Has it ever struck your curious mind how 4G evolved from simple Push to talk system ?

  • Is there any governing body which regulates the spectrum ?

  • what kind of services we will have in next generation of communication?

  • So friends, Lets start the journey of wireless communication.

  • Mobile radio telephones were introduced for military communications in the early 20th

  • century. Car-based telephones was first tested in Saint Louis in 1946. This system used a

  • single large transmitter on top of a high rise building. A single channel was used for

  • sending and receiving similar to a half duplex system. To talk, the user pushed a button

  • that enabled transmission and disabled reception. Due to this, these became known aspush-to-talk

  • systems in the 1950s. To allow users to talk and listen at the same time, IMTS (Improved

  • Mobile Telephone System) was introduced in the 1960s. It used two channels one for sending

  • and one for receiving bringing telecommunication to full duplex mode.

  • In the 1970s Private companies have started developing their own systems to evolve the

  • existing further..Those private systems are Analogue Mobile Phone System, used in America,

  • Total Access Communication System and Nordic Mobile Telephone, used in parts of Europe

  • and Japanese Total Access Communication System, used in Japan and Hong Kong.

  • Independently developed systems are called as 1st Generation communication. It was introduced

  • in 1982 by Bell Labs and popularly known as Advanced Mobile Phone System (AMPS). The key

  • idea here was to divide geographical areas into cells. and each cell was served by a

  • base station so that frequency reuse can be implemented. As a result AMPS could support

  • 5 to 10 times more users than IMTS. Major concern for the 1st generation was weak Security

  • on air interface, full analog mode of communication. and No roaming.

  • Now, To implement roaming. Individual organisations started working under one umbrella, European

  • Telecommunications Standards Institute (E T S I) and developed 2nd Generation system.

  • Second generation cellular telecom networks were commercially launched in 1991 in Finland

  • based on GSM standards. It could deliver data at the rate of up to 9.6 Kbps.

  • Three primary benefits of 2G networks over their predecessors were.

  • phone conversations were now digitally encrypted. It was significantly more efficient on the

  • spectrum and allowed far greater mobile phone penetration level.

  • 2G introduced data services for mobile, starting with SMS text message.

  • Further To achieve higher data rates GSM carriers started developing a service called General

  • Packet Radio Service (GPRS). This system overlaid a packet switching network on the existing

  • circuit switched GSM network. GPRS could transmit data at up to 160 Kbps

  • The phase after GPRS is called Enhanced Data Rates for GSM Evolution (EDGE). It introduced

  • 8 PSK modulation and could deliver data at up to 500 Kbps using the same GPRS infrastructure.

  • During this time the internet was becoming popular and data services were becoming more

  • prevalent. Post 2.5G, Multimedia services and streaming started growing and Phones now

  • started supporting web browsing. Development of 3G,

  • 3GPP UMTS, the Universal Mobile Telecommunications System succeeded EDGE in 1999.This system

  • uses Wideband CDMA ( W-CDMA) to carry the radio transmissions, and often the system

  • is referred to by the name WCDMA.

  • Now before we go further let us understand how the governing bodies were developed.

  • In the interests of producing truly global standards, the collaboration for both GSM

  • and UMTS was expanded further from ETSI to encompass regional Standards Development Organizations

  • such as ARIB and TTC from Japan, TTA from Korea, ATIS from North America and CCSA from

  • China. The successful creation of such a large and

  • complex system specification required a well-structured organization. This gave birth to 3GPP and

  • which worked under the observation of ITU-R. ITU-R is one of the sector of ITU, Its role

  • is to manage the international radio-frequency spectrum and to ensure the effective use of

  • spectrum. ITU-R defines technology families and associates specific parts of the spectrum

  • with these families. ITU-R also proposed requirement for radio technology.

  • 3 organization started developing standards to meet the requirements proposed by ITU-R.

  • 3GPP, 3GPP2, IEEE Evolution of 3gpp, started from GSM to Long

  • term evolution Advanced. Evolution of 3GPP2, started from IS95 to CDMA

  • Revision B. Evolution of IEEE started from 8o2.16 Fixed

  • Wimax, to 8o2.16M

  • Since 3GPP was dominated and widely accepted, we will only incorporated roadmap evolved

  • by 3GPP.

  • Now coming back to 3rd Generation. The goal of UMTS or 3G wireless systems was

  • to provide a minimum data rate of 2 Mbit/s for stationary or walking users, and 384 kbit/s

  • in a moving vehicle. 3GPP designated it as Release 99.

  • The upgrades and additional facilities were introduced at successive releases of the 3GPP

  • standard. Release 4: This release of the 3GPP standard

  • provided for the efficient use of IP, this was a key enabler for 3G HSDPA.

  • Release 5: This release included the core of HSDPA. It provided reduced delays for downlink

  • packet and provided a data rate of 14 Mbps. Release 6: This included the core of HSUPA

  • with a reduction in uplink delay it enhanced uplink raw data rate of 5.74 Mbps. This release

  • also included MBMS for broadcasting services. Release 7: This release of the 3GPP standard

  • included downlink MIMO operation as well as support for higher order modulation of up

  • to 64-QAM. Either MIMO or 64-QAM could be used at a time.Evolved HSPA provides data

  • rates up to 28 Mbit/s in the downlink and 11 Mbit/s in the uplink.

  • This brings us to the most awaited part. Long term evolution (LTE)

  • Initial goal of telecommunication was mobility and global connectivity, but as the technology

  • evolved the Services started expanding. Now Services were not restricted to Voice and

  • SMS only. For This expansion and efficient execution in LTE, whole new architecture was

  • adopted for both non Radio part ( SAE System Architecture Evolution) and Radio part using

  • pure IP Architecture (packet switching)

  • To fulfill the requirement proposed by ITU-R, Study group formed and LTE standardization

  • began in 2004. Large number of telecom companies collaborated to achieve their common vision.

  • In June 2005 Release 8 was finally crystallized after series of refining.

  • Some of the significant features of Release 8 were-

  • reduced delays, for both connection establishment and transmission latency;

  • increased user data throughput; • increased cell-edge bit-rate, for uniformity

  • of service provision; • reduced cost per bit, implying improved

  • spectral efficiency. • simplified network architecture;

  • seamless mobility, including between different radio-access technologies;

  • reasonable power consumption for the mobile terminal.

  • These requirements were fulfilled by advancement in the underlying mobile radio technology.

  • The three fundamental technologies that have shaped the LTE radio interface design were:

  • multicarrier technology, multiple-antenna technology, and the application of packet-switching

  • to the radio interface.

  • As a result of intense activity by a larger number of organisations, the specifications

  • for the Release 8 was completed by December 2007. The first commercial deployment took

  • place by the end of 2009 in northern Europe.

  • In The subsequent releases multiple services such as Multi Cell HSDPA, HETNET, Coordinate

  • Multipoint, Carrier Aggregation, Massive MIMO and many more were targeted for a rich customer

  • experience.

  • Now it's time to move from services to multiservices approach, in other word from LTE Advanced

  • to next Generation communication system which is 5th Generation.

  • Features have been planned to be added in the 5th Generation Or next generation systems

  • are, Pervasive networks : where a user can concurrently

  • be connected to several wireless access technologies and seamlessly move between them.

  • Group cooperative relay: This is a technique that is being considered to make the high

  • data rates available over a wider area of the cell.

  • Cognitive radio technology: it would enable the user equipment / handset to look at the

  • radio landscape in which it is located and choose the optimum radio access network, modulation

  • scheme and other parameters to configure itself to gain the best connection and optimum performance.

  • Smart antennas: Another major element of any 5G cellular system will be that of smart antennas.

  • Using these it will be possible to alter the beam direction to enable more direct communications

  • and limit interference and increase overall cell capacity.

  • So friends, here we have covered history of wireless communication starting from single

  • channel based Push to Talk system to, multiple services based purely advanced digital communication

  • system. In the future videos we will start exploring

  • fundamental of advanced communication which will help us to understand next generation

  • system better. Don't forget to subscribe to our channel,

  • like our videos and comments your views, or suggestions. Thanks for watching

Has it ever struck your curious mind how 4G evolved from simple Push to talk system ?

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2--從1G到4G,再到5G--通信的發展。 (2 - From 1G to 4G & Towards 5G - Evolution Of Communication)

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    趙浚成 發佈於 2021 年 01 月 14 日
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