Dear Dr Ismat,

Your question is multi dimensional and broadbanding. The answer may be a chapter in a book for telecommunication. The communication systems are conveyors of information from sources to destinations via communication mediums. The information sources are audio, video and data. They are converted into digital data streams.It is the demand from the customers to transmit and receive information which dictated and still dictating the band width need. Any digital communication system is characterized by an input bit rate, a bandwidth and a minimum signal to noise ratio S/N for certain specific bit error rate. As we all know, these parameters are related by the Shanon theorem:

The maximum channel capacity C = The bandwidth B logarithmic 2 ( 1+ S/N)

As the S/N is physically limited, To increase the data rate we have to increase the bandwidth.More traffic necessitates more band width. More bandwidth can practically achieved by wires or wireless. Every communication medium has maximum bit rate and consequently to increase the band width one has to duplicate the medium. That is more wires and more frequency reuse.

The broadband communication is existing since relatively long times for long distance transmission such as the coaxial cables, the microwave links, the optical fiber and the satellite. With the tremendous increase in data communications and mobile communications came the need for broad band communications in the local loop and short communication distances. The communication is now driven by computers and very large scale integrated electronics. Many communication concepts are old, they could be realized by these two technologies.

This was only an introduction by me for the white paper broadband technology overview in the link http://www.corning.com/docs/opticalfiber/wp6321.pdf

I found it useful in answering your question.

Thank you

Dear Dr Ismat,

Your question is multi dimensional and broadbanding. The answer may be a chapter in a book for telecommunication. The communication systems are conveyors of information from sources to destinations via communication mediums. The information sources are audio, video and data. They are converted into digital data streams.It is the demand from the customers to transmit and receive information which dictated and still dictating the band width need. Any digital communication system is characterized by an input bit rate, a bandwidth and a minimum signal to noise ratio S/N for certain specific bit error rate. As we all know, these parameters are related by the Shanon theorem:

The maximum channel capacity C = The bandwidth B logarithmic 2 ( 1+ S/N)

As the S/N is physically limited, To increase the data rate we have to increase the bandwidth.More traffic necessitates more band width. More bandwidth can practically achieved by wires or wireless. Every communication medium has maximum bit rate and consequently to increase the band width one has to duplicate the medium. That is more wires and more frequency reuse.

The broadband communication is existing since relatively long times for long distance transmission such as the coaxial cables, the microwave links, the optical fiber and the satellite. With the tremendous increase in data communications and mobile communications came the need for broad band communications in the local loop and short communication distances. The communication is now driven by computers and very large scale integrated electronics. Many communication concepts are old, they could be realized by these two technologies.

This was only an introduction by me for the white paper broadband technology overview in the link http://www.corning.com/docs/opticalfiber/wp6321.pdf

I found it useful in answering your question.

Thank you

Very Good Reference. Provides a really broad view of simultaneous Transmission /Reception of Multiple Signals like VOD,HDTV etc. Deals with Cable and Wireless transmissions.Generally Optical Fiber Cables are considered to be capable of providing Good Band Width,for large number of Signals.

This reference can be a good beginning for Search. If you go for Space Signals (Statistical Communication) you may have to go for Co-relaters, Weiner Hoft Filters etc. Refer 'Statistical Communication Theory' -Y.W.Lee Book.

P.S.

Thank you my dear colleagues. The white paper suggested by Dr. Zekry is a nice one, though it is a bit lacking the recent trends as it is dated 2005, e.g. the broadband of the 4G. Noticeably, those who wrote the paper seemed to contrast broadband wireless against broadband over the wire-line. This is nice as this is one objective of my question. They reviewed the wireline commenting mainly on the deficiencies and difficulties of wire-line broadband (e.g. "clearly neither ADSL or SDSL can meet the bandwidth requirements for HDTV", "Most, broadband by Power line-BPL- systems at present are limited to a range of 1km", " ...etc). But when they commented on the wireless, they were unable to say that wireless broadband can be a real competitive, I wonder what they will say now if they re-wrote their paper today taking into consideration the recent advancements and high data rates of HSPA+ and 4G-LTE advanced of >1Gbps peak traffic.

In my view, and if I will narrow my question to comparing current wireless and wireline broadband, I certainly go with the wireless as that will be dominant. Surely, not shocking to any one. I would say that wireless will even surpasses itself and more will be seen. I mean by more, even higher rates compared to wireline. This is because of reasons of weaknesses on the wireline side -that limits it- and strengths on the wireless side as I will outline.

On the wireline side, whatever the case, we have first the cost issue of wiring and infrastructure which is a burden (and even those technologies utilizing exiting wires, e.g. DSL and Broadband Powerline (BPL), they have their own limitations as outlined in the white paper itself). Second, wireline communication suffers higher attenuation at larger distances (cable attenuation is linear with distance) which necessitates repeaters (extra cost) while wireless is attenuated linearly with distance log (per decade basis and not per unit length). This what makes a satellite communication possible. Of course, the wireline technology enjoys that bandwidth can be doubled by laying wires in parallel and a nice channel with good signal conditions.

On the wireless side, on the other hand, we have a vagarious channel with limited bandwidth. Therefore, the two points of BW and S/N ratio contributing to data throughput (as Dr Zakrey raised out above) are limited. This is true. However, many wireless advancements are now in place to overcome these two.

- First, regarding BW, more efficient spectral techniques are in place and more importantly, the use of spatial multiplexing using MIMO techniques to increase the throughput (in effect I like calling this "wireless channel wiring", i.e. doubling the MIMO we double the paths between the transmitter and the receiver that can double the throughput which looks as we doubled the wires (BW) -of course, no wires).

- Second (S/N ratio): the methods to overcome the channel vagaries of multipaths and interference from others are continuously developing. Amongst these are equalization methods, diversity techniques, interference cancellation and management, beamforming antenna, ...etc. Lately, small cells, e.g femto, pico,...cells, tend to allow for higher throughputs because of the improved channel conditions. Also, new methods are devised in 4G to overcome the low S/N ratio of cell edge users like the coordinated multipoint (CoMP) in which more one base station cooperate on sending the signal to the mobile unit thereby increasing S/N (coherence reception).

I think that wireless is currently a real competitor with most wire line technologies. But, If wireless data rates can't compete with the high data rates of a direct fiber, e.g. Fiber to Home, wireless have other advantages that can't be overlooked, cost as mentioned, mobility, and ease of upgrading (as you don't have to change anything in between the transmitter and the receiver). I think the driving for wireline will be the wireless itself. Wireline will continue to be needed for backhaul, especially with the outspread of small cells like Femto cells which require a DSL or broadband backhaul. Thanks. @AlDmour.

Hi Isamat

From my point of veiw optical fiber is the emerging one offering very high data rates. It overwhelms the wireless technologies like LTE and Wi-max too in delivering high data rates.

Please refer to the links below

http://venturebeat.com/2012/02/15/the-next-big-trends-in-broadband/

www.akamaiuniversity.us/PJST8_1_118.pdf

These may be helpful in this discussion

Thanks

Sailaja

Dr Adam, your contribution is appreciated any time.

Sailaja is saying that fiber is the emerging technology offering very high data rates. No one can argue this as fiber will be the backhaul for the high data rates of the wireless cell of point to multipoint nature. Fibers existed long before the current wireless technologies, therefore they are not recent but recent ways of increasing their bit rates are explored. I wish if you or some one in this field can tell us about these developments in fiber technology. Thanks Sailaja.

Setting fiber aside, other wireline technologies cable technology- coax, twisted pair DSL, power line broadband, and even fiber ended with cable, all seem lagged or started to lag behind wireless broadband, especially when considering 4G broadband. The factors that were mentioned by Dr Adam and me above are partial list of the factors that will enhance wireless broadband more and more.

For example, as outlined in the article: LTE vision for 2020 (http://www.3gpp.org/IMG/pdf/wiseharbor.pdf) many technologies and features introduced in previous releases are being enhanced and supplemented with new additions in Releases 12 and 13, 256QAM, coordinated multiple point transmission,. 3D MIMO and massive antenna beamforming with arrays of as many as 64 antenna elements. These developments will increase network capacity, while also providing more consistent service quality, with the product of three compounding factors

- 3x increase in spectrum employed

- 6x improvement in spectral efficiency

- 56x higher average cell density

So, Imagine improvement figures of 3 x 6 x 56 = 1,008 !. Can we ask for more !. Thanks.@AlDmour.

Sorry Dr. Adam as I forgot to comment on your question to me above : (BTW - Ismat, can we be sure that the attenuation of a cable changes in linear with its length or have I missed/mixed sth?). My answer that it something you surely know but I probably didn't explain my words properly.

Attenuation of cables is linear because it is the result of voltage drop on cable per unit length (IR drop) and power loss (I2R) is linear, so every unit length suffers a certain fixed decibel per unit length as resistance is α L (length or distance). However, for wireless link power loss (assuming free space) is the result of the continuously increasing size of circles emanating from antenna. In free space will have loss α d^2 (Friss equation) which results in 20 dB/decade (or 20 logdB) loss due to distance. In other environments, i.e. the power loss doubles whenever the distance is increased 10 folds (in contrary to wireline where loss doubles when distance doubles. This makes the loss higher for wireless after a certain distance compared to wireless. The following numerical example from (the book by Pahlavan and Krishnamurthy, Principles of wireless networks, a unified approach, 2002, page 78) explains this:

The category 3 UTP wires used for Ethernet lose around 13 dB per 100 meters of distance. Therefore, the path loss for 1 km is 130 dB. In free-space, the path loss of a 1 GHz radio in the first meter is around 30 dB (with an omnidirectional dipole antenna), and after that the path loss is 20 dB per decade of distance. Therefore, path loss at 100 meters is 70 dB and for 1 km it is 90 dB. Indeed for 130 dB path loss, the 1 GHz radio can cover 1,000 km"!.

Thanks. @AlDmour.

Dear Dr Adam, Thanks a lot, I think I will do, especially for the first 3 (3x, 6x, 56x) and I suggest you handle the second set (extending ..,energy.., managing). This way we activate together a serious beneficial discussion tackling near explosive future of the wireless era. Thanks again. @AlDmour