The History Of The Wireless Technology

Published Date: 02 Nov 2017

Operating System

Telemedicine is one of the fastest growing field in the area of managed health-care. It may be formally defined as the use of medical information being exchanged from one place to another via electronic communications to improve patients’ clinical health. This is new technology where two way video, emails, smart phones, wireless tools and other forms of telecommunications technology are used.

Telemedicine is not a separate branch of medical specialty. The products and services offered by this technology is the outcome of investment by health care institutions.It has made lives easier both for the doctors and the patients. Now the doctor can advise the patient sitting half the way round the world treating them just like the patient is right in front of him.

With so many innovations happening in this area and with the advent of internet and infrastructures playing such an important role, it is not advisable to run such a critical applications like high quality audio and video without proper quality of service built on to the network. Since the patient’s life could be at stake the quality of services could not be compromised with.

Homeopathy:

It is a branch of medical science that was first developed by Samuel Hahnemann, in 1796. Ayurveda in greek means like suffering. The main technique that is used here is that the substance that causes the symptoms of disease in healthy people will cure similar symptoms in sick people.

Ayurveda:

Ayurveda in Sanskrit means life-knowledge. The cure for various diseases are found in the form of herbs and plants and the various technique with these are applied also depends which are mentioned in ayurvedic texts like SusrutaSamhitaand the CharakaSammhita.

Naturopathy:

It is an alternative medicine absed on the belief that all living aorganisms are fundamentally different from non-living entities because hey contain some non-physical element or in other word vitalism. This believes that a special energy called vital energy guides all the bodily processes.

Unani:

It means Greek medicine which was taught by Greek physician Hippocrates, and is practiced in South Asia.

The services that can be provided by telemedicine.

-Primary care and specialist referral services that provides an allied health professional providing a consultation to the patient or a specialist assisting the patient. This includes the use of live interactive video or the use of stored or recorded transmission of diagnostic images for later reviews.

Remote patient monitoring- uses devices to send patient’s health data to a health agency or to a remote diagnostic testing facility.

Consumer medical and health information- includes the use of internet to the consumer to obtain health advice.

Medical education-provides medical education to the professional.

The delivery mechanism that can be used are:

Networked programs –it includes tertiary health care centers of in rural areas linking it to its main branch in some city. The links may be connected by using dedicated high-speed lines or internet for telecommunication links.

Point to point connections-it uses private high speed links that are used by hospitals that provide telecommunication services to independent medical service providers.

Monitoring center links-are used for cardiac, pulmonary etc and other monitoring based data which are provided by patient directly from his home to the service providers.

Web based e-health patient services sites- provides direct consumer outreach over internet.

Wired communication has pros cons which are discussed below:

Pros:

they are reliable and are not affected by other wireless signals such as cellular phones microwaves etc.

its cheap.

has high life expectancy.

has high speed.

provides Quality of Service.

Cons:

affected by moisture and other weather conditions.

can be affected by noise generated by machinery and magnetics.

Thus the proper support for QoS was a challenge in wireless network rather than wired one because the various issues like bandwidth scarcity, latency and high bit error rate. At the time of transmission due to lot of disturbances the quality might have to suffer.

Wireless technology:

Wireless isn’t really a new technology. These were first used in transmitting AM and FM to televisions and radios in the early 1950’s. the military has been using "line of sight" micro-wave towers for decades. Nowadays the most common wireless technology which everyone knows is cellular phones. However this technology has several problems. The pros and cons of wireless technology are also discussed below:

Pros:

it is convenient

its range is very large

it has high life expectancy.

Cons:

mostly affected by other wireless signals.

high price.

signals can be easily intercepted.

speed id much slower than wired.

does not provide QoS.

QoSare majorly affected by various factors which can be divided into human and technical factors. While human factors could be dealt with upto some extend ,the technical factors that include: reliability , scalability ,effectiveness ,maintainability, etc. Many things could happen during the transmission resulting a few problems , some of which are listed below:

Low throughput

If many data streams get the same scheduling priority then the bit rate that can be provided to a certain data stream may be too low for real time multimedia.

Dropped packets:

Some packets might get failed to be delivered due to several reasons causing the packet to be retransmitted altogether causing sever delays.

Errors:

Packets might get corrupted due to bit errors cause by interferences.

Latency:

The packet might take a long time to reach its destination, because it gets held up in long queues.

Jitter:

The packets might choose different path to reach its destination creating different delays which would affect seriously the quality of audio and video.

Out of order delivery:

The jitter may cause different delays due to which the packets may reach in different order.

Now due to these few problems, in this paper OSI protocol stack is being used i.e. Open Systems Interconnection. OSI protocols are split into seven layers. It has several layers starting with physical hardware components to the user interfaces at the software application level. Each layer processes the relevant information and passes it to the level below. Each layer adds its own encapsulation to the information before it passes to the next level. Their various levels are named as follows

Physical layer, data link layer, WAN protocol architecture, IEEE 802 LAN architecture, Network layer, transport layer, session layer presentation layer,application layer.

Now in any field of research nowadays the proper knowledge of the related area is very important. And especially in the areas of computer science our main motto before developing a proper system that contains data in a very atomic basis Data Mining is considered to be very important. Data mining is nothing but a computational process of discovering patterns in large data sets involving methods at the intersection of artificial intelligence, machine learning, statistics and database systems. The overall goal of the data mining is to extract information from a data set and transform it into an understandable structure for further use. As discussed in this paper the medicine have its unique history especially in India. Data mining helps us to gather all such relevant past and present data here which is the knowledge about the medicines and convert it into proper information. In this data mining we need to evaluate the data by applying methods and algorithms for getting the clear view of the data which is stored in repository. It helps in planning for the future. It also helps in various applications such as education, business and scientific application.

Data mining in education view:

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Data mining plays an important rule education system for giving proper information to the students. It increases the interest in the students for education. The goals of educational data mining research are as follows:

Predicting students’ future learning behavior by creating student models that incorporate such detailed information as students’ knowledge, motivation, metacognition, and attitudes.

Discovering or improving domain models that characterize the content to be learned and optimal instructional sequences.

Studying the effects of different kinds of pedagogical support that can be provided by learning software; and

Advancing scientific knowledge about learning and learners through building computational models that incorporate models of the students, the domain, and the software’s pedagogy.

In this paper the data mining in the educational view is divided into three categories namely 1.predictable changes in future 2.grouping of objects 3.network among data mining.

Predictable changes in future

It allows the student to change the future. This also allows them to assess their performances. Further it has been divided into three sub categories. It entails developing a model that can infer a single aspect of the data from some combination of other aspects of the data. The example of prediction could be detecting such student behaviors as when they are gaming the system, engaging in off-task behavior, or failing to answer a question correctly despite having a skill. Prediction shows promise in developing domain models, such as connecting procedures or facts with the specific sequence and amount of practice items that best teach them, and forecasting and understanding students educational outcomes, such as success on post test tutoring.

Classification

- it is the problem of identifying to which set of categories a new observation belongs, on the basis of training set of data containing observations whose category membership is known. An algorithm that implements classification, especially in a concrete implementation, is known as a classifier.

Regression

- it is a statistical technique for estimating the relationships among variables. There are several types of regression.

Density estimation

- it is the construction of an estimate, based on observed data, of an unobservable underlying probability density function.

Apart from these classifications discussed in this paper there are some other categories are :

Relationship mining

: involves discovering relationships between variables in a dataset and encoding them as rules for later use. Foe example, relationship mining can identify the relationships among products purchased in online shopping.

Association rule mining can be used for finding students mistakes that co-occur, associating content with user types to build recommendations for content that is likely to be interesting, or for making changes to teaching approaches. These techniques can be used to associate student activity, in a learning management system or discussion forums, with student grades or to investigate such students.

Sequential pattern mining build rules that capture the connections between occurrences of sequential events, for example, finding temporal sequences, such as students mistakes followed by help seeking.

Grouping of objects:

Clustering:

Similar objects grouped together are known as cluster. And this process is known as clustering. It refers to finding data points that naturally group together and can be used to split a full dataset into categories. Examples of clustering applications are grouping students based on their learning difficulties and interaction patterns, such as how and how much they use tools in a learning management system, and grouping users for purposes of recommending actions and resources to similar users. Clustering can be used in any domain that involves classifying, even to determine how much collaboration users exhibit based on postings in discussion forums. There are two important algorithm for clustering those are K-mean and Expectation- maximization algorithm(EM clustering).

K-mean clustering

–it is a method of cluster analysis which aims to partition n observations into k clusters in which each observation belongs to the cluster with the nearest mean. This results in partitioning of the data space into Voronoi cells.The standard algorithm is known as k-means algorithm or Lloyd’s algorithm.

Expectation-maximization algorithm or EM clustering

It is an iterativemethod for finding maximumlikelihood or maximum a posteriori(MAP) estimates of parameters in statistical models, where the model depends on unobserved latent variables. This is used when equations cannot be solved directly or are not easily solved. In addition to the variables ,it also involves latent variables. The EM algorithm is used to find the maximum likelihood parameters of a statistical model in cases where the equations cannot be solved directly. Finding a maximum likelihood solution requires taking the derivatives of the likelihood function with respect to all the unknown values- eg. Both the parameters and the latent variables – and simultaneously solving the resulting equation.

Network among data mining:

The relationship among the various variables are acknowledged here

It has again broadly divided into four types.

Association rule mining:

it is a popularly used for discovering interesting relations between variables in large databases as it is well researched. Based on the works of RakeshAgarwal, it includes the concept of finding regularities and something common between the articles based on their products. Like for example {onions, potatoes}={burgers} found in the sales data of a supermarket would indicate that if a customer buys onions and potatoes he is more likely to also buys some bread or ketchup. It is also used to predict the errors likely to be made by students when they are solving a problem. Association rules are usually required to satisfy a user-specified minimum support and a user-specified minimum confidence at the same time. Association rule generation are usually split into two separate steps:

All the frequent items are grouped together in a database.

These frequent itemsets and the minimum confidence constraints are used to form rules.

Correlation mining:

it provides a method for clustering a set of objects into optimum number of clusters without specifying that numberin advance. It also relates to a different task, where correlations among attributes of features vectors are assumed to exist guiding the clustering process. Correlations among subsets of attributes result in different shapes of clusters. Hence, the similarity between cluster of objects is defined into account the local correlation patterns. With, this notion, the term has been introduced in simultaneously with the notion discussed. Correlation clustering can be shown to be closely related to biclustering.

Sequential data mining

-it orders everything. The sequence of information to be followed is also determined here. For example the link from one page to another is ordered using this. It is helpful in improving student’s performances. It is a series of alphabets or numbers. The other types of sequential data are :Spatial data(biological sequence, text document, a computer program, web page, a missile trajectory) and Temporal sequence data(speech, movie clips, stock prices, a series of web clicks).

Casual data mining

-it is helped to compare one action with another. Measures such as conditional probability and correlation have been used to infer rules of the form "the existence of item A implies the existence of item B". However such rules indicate only a statistical relationship between A and B. They do not specify the nature of the relationship: whether the presence of A causes the presence of B, or the converse, or some other attribute or phenomenon causes both to appear together. In applications, knowing such casual relationships is extremely useful for enhancing understanding and effecting change.

Text mining

-refers to the process of deriving high-quality information from text. It is generally derived by devising patterns and trends through means such as statistical pattern learning. It is closely related to web-mining which is a technique to determine patterns from the web. Like for example providing the web user with only those e-mails or advertisements which are relevant to his needs which is evaluated using statistical patterns.Text analysis involves information retrieval, lexical analysis to study word frequency distribution, pattern recognition, tagging, information extraction, data mining techniques including link and association analysis, visualization, and predictive analytics. The overarching goal is, essentially, to turn text into data for analysis, via application of natural language processing and analytical methods. It has its application in various fields like :

security applications

biomedical applications

software applications

online media applications

marketing applications

sentiment analysis

academic applications

Network analysis

- it gives the idea about network information using network theory which concerns itself with the study of graphs as a representation of either symmetrical or asymmetrical relations between discreet objects.It is used to analyze online thread. Network analysis helps to keep the track of online education communities.

Literature survey:

The key features of telemedicine are voice, video and data. These things are to be taken care of and made sure that there is no wastage of data. The critical application involved in this like audio and video should be executed with high quality QoS, which it lacks.

The transfer of digital data is taken care of by IETF- internet engineering task force that develops and design internet standards. The IETF is a large open international community of network designers, operators, vendors, and researchers concerned with the evolution if the Inernet architecture and the smooth operation of the internet. It is open to any interested individual.

It has standardized DVOIP – digital video over IP- to convert video streams into packets and adding headers and timestamps into each IP packet.The quality of the video stream should be high and the response time taken should be less. Due to the traffic, the bandwidth specification should be done like its maximum, minimum, and average bandwidth. The traffic of each data stream should be treated differently.

DVOIP

- it uses some existing standard video codec to reduce the program material to a bit stream and then to use an IP network to carry that bitstream encapsulated in a stream of IP packets. Some of the problems faced during IP network transmission are packet loss, network delay variation, timing reconstruction, adequate bandwidth, etc.

Packet loss- it should have small packet loss rate caused by low-probability statistical congestion events and amplification of bit errors in the underlying hardware. The forward error correction technique is used mostly to ensure that the encoded can be reconstructed even if the few packets have been lost.

Network delay variation- the delay in the reaching of the packets to its required destination can be kept minimum by using a high-speed backbone and ensuring that video traffic does not encounter excessive queue delays. This is usually done by ensuring that the network is not too close to its full capacity.

Timing reconstruction- the recovery of the video signal sometimes very difficult to be synchronized by making recovery of the underlying timing of the video far more difficult.

Adequate bandwidth- the video over IP will only work if the network is capable of carrying the content with some reasonable maximum packet loss rate. In reality it will not work at overloaded networks. To solve this the packet cannot be altered, the network engineering has to be dealt with from its root level.

Connection admission control- it has a job to ensure that data packets are not sent through congested routes as it could result in time delay. It also ensures Traffic differentiation, real time traffic management and congestion control. It also handles the allowance of bandwidth when the real time video are used because the data packets vary if the raw data is sent or a compressed form is sent.

At present the telemedicine applications focuses mainly on:

reliability

efficiency

portability

functionality

usability

maintainability

Telemedicine system is being used in fields like:

Tele-radiology – it is the transmission of radiological patient images, such as X-rays, CTs and MRIs, from one location to another for the purposes of sharing studies with other radiologists and physicians. It improves patient care by allowing Radiologists to provide services without actually having to be at the location of the patient.

Tele-pathology –it is the practice of pathology at a distance. It uses telecommunications technology to facilitate the transfer of image-rich pathology data between distant locations for the purposes of diagnosis, education, and research.

Tele-cardiology – it is the transmission of ECG or electrocardiograph using telephone and wireless.

Tele-oncology

Tele-homecare- it involves the delivery of healthcare services to patients at home through the use of telecommunications technology, which enable the interaction of voice, video, and health-related data.

Tele-surgery – is the ability for a doctor to perform surgery on a patient without being physically present at the patient’s location. A robot surgical system is used to perform the actual surgery which has one or more arms, master controller and a sensory system giving feedback to the doctors and thus they control the robotic arms.

Tele-psychiatry – it includes a videotelephony between the patient and the psychiatrist for treatments.

The bandwidth used for data transmission vary with various purposes. Although standard telephone lines could be used, higher bandwidth are for many other telemedicine application. Disaster management team need to always arrange for alternative communication medium even though they have setup a standard medium. The telecommunication methods used are:

Single channel

- it uses only one channel at a time at a given frequency and bandwidth. In it the satellite bandwidth is dedicated to a single source. This makes sense if it is being used for something like satellite radio, which broadcasts continuously.Its very common application is voice, where a small amount of fixed bandwidth is required. Its advantages could be listed as below:

Simple and reliable technology

Low-cost equipment

Any bandwidth(up to a full transponder)

Usually 64 bit/s to 50 Mbit/s

Easy to add additional receive sites(earth stations)

It has disadvantages that are listed below

Inefficient use of satellite bandwidth for burst transmissions, typically encountered with packet data transmission

Usually requires on-site control

When used in remote locations, the transmitting dish must be protected.

A dish which is moved out of alignment can result in fines as high as $1100 per minute from the satellite operator.

Trunked

– it allows a few radio frequency channels among a large group of users. It is a complex type of two way radio computer controlled system. The traffic channel are distributed dynamically based on their availability. Instead of providing particular radio channel, they are assigned a "talk group". When any individual in that group wants to talk to another individual in that group, a vacant radio channel is automatically found by the system and allocated to them. The primary purpose of this type of system is efficiency; many people can carry many conversations over only a few distinct frequencies. Trunking is used by many government entities to provide two-way communication for fire departments, police and other municipal services, who all share spectrum allocated to a city, county, or other entity. Its advantage is that with any given number of users units, not everyone will need channel access at the same time, therefore fewer discrete radio channels are required. Another way, with a given number of radio channels, a much greater number of user groups can be accommodated.

Microwave transmission

- this the technology of transmission of the data over large distances by using microwaves. It is highly directional is appropriate for point to point communication. Its capacity is very large due its high frequency. It uses small wavelength that allows conveniently-sized antennas to direct them in narrow beams, which can be pointed directly at the receiving antenna. This allows nearby microwave equipment to use the same frequencies without interfering with each other, as lower frequency radio waves do.

Its disadvantage are listed below

it is limited to line of sight. That is they cannot pass around hills or mountains as lower frequency radio waves can.

Affected greatly by environmental constraints, including rain fade

Have very limited penetration capabilities through obstacles such as hills, buildings and trees

Sensitive to high pollen count

Signals can be degraded during solar proton events.

LAN-

local area network is a small network covering a small area or office. It has high data transfer rate. Its only disadvantage is that it is very limited. It interconnects computers in a limited area such as a home, school, computer laboratory, or office building using network media.

GSM-

global system for mobile is a standard set to describe protocols for cellular networks used by mobile phones. It is cellular network, which means that cell phones connect to it by searching for cells in the immediate vicinity. It is widely used because of its mobility, portability and security.GSM standard was developed as a replacement for first generation analog cellular networks, and originally described a digital, circuit switched network optimized for full duplex voice telephony. This was expanded over time to include data transport via GPRS(general packet radio services) and EDGE(enhanced data rates for GSM evolution or EGPRS).

In this paper using data mining technique different data transmission techniques are tabulated. Based on the identity of what typr of traffic stream is being taken over, the data are separated for its necessary to group them according to QoS metrics. Some of the data to be transferred cant compromise on data loss at all, while some of the data cannot compromise on delay at all though they both be CBR-constant bitrate. For example an e-mail cannot be considered to be same as an ECG report while both are CBR, because a delay in the ECG report could result in life or death.

ATM

- Asynchronous Transfer Mode is designed to unify telecommunication and computer-networks. It has a different approach that from IP or Ethernet that uses variables packets. It provides data-link layer services that run over a wide range of physical layer links. It is a carriage of complete range of user traffic, including voice, data, and video signals. It uses asynchronous time-division multiplexing, and it encodes data into small, fixed-sized cells. It has functional similarity with both circuit switched networking and small packet switched networking. It uses a connection-oriented model in which a virtual circuit must be established between two end-points before the actual data exchange begins.

MPLS

–multipath layer switching is a mechanism in high-performance telecommunication networks that directs data from one network addresses. Like ATM it also develops a virtual link between two end points. It is highly scalable, protocol agnostic, data-carrying mechanism. In an MPLS network data packets are assigned labels. It allows to create end-to-end circuits across any type of transport medium, using any protocol. The primary benefit is to eliminate dependence on a particular OSI model data link layer technology, such as ATM etc. and eliminate the need for multiple layer-2 networks to satisfy different types of traffic.

In both technologies, connections are signaled between endpoints, connection state is maintained at each node in path, and encapsulation technique are used to carry data across the connection.

Although they both support QoS, they lack in the terms of mobility and scalability.

UMTS

- Unified Mobile Telecommunication System –it a mobile cellular system of third generation for networks based on GSM standard. It uses wideband code division multiple access radio technology to offer greater efficiency and bandwidth to mobile networks operators. It supports high speed data transfer. But the only thing it lacks is that it does not support QoS. It supports maximum theoretical data transfer rates of 42Mbit/s . Users in deployed networks can expect a transfer rate of up to 384 kbit/s R99 handsets.

Therefore technology that is preferred over all the others these days is IEEE 802.11 WLAN computer communication because it provides proper scalability, mobility, reliability, low cost. IEEE 802.11 is set of standards for implementing wide area network (WLAN). These standards provides the basis for today world Wi-Fi brand. The earlier versions of IEEE were 802.11a & b. They both were incompatible to each other and the users were confused as to what was to be used. Then came the 802.11g which overcame the difficulties against higher data rates, extended range and compatibility with already installed Wi-Fi devices. Till now the latest version is 802.11ad which yet to be released in early 2014 which will have throughput of up to 7 Gbit/s against that of earliest version which had mid-20 Mbit/s.

In this paper the version that was used is 802.11g. The video is sent as a data is broken into frames using a convertor which is in-built. Those frames are transferred via the network are again got back at the destination.

Knowledge management system:

It comprises of the range of strategies and practices used in an organization to identify, create, represent, distribute and enable adoption of insights which comprise knowledge.

In this paper the design that is formulated is divided into two parts that is medical expert station and patient station. The primary goal of this design, and therefore this whole paper is thatthe patient is being treated without the physical presence of the medical expert at the patient’s area. The medical expert treats the patiet in some rural area by getting his medical condition comprising of both video and audio and some digital data to formulate his condition and determine the kind treatment he needs to undergo so as to become fit. The data relating to the patient’s condition is being sent over by the help of cross layer optimizer that optimizes the physical layer, data link layer and application layer which is given the data that it optimizes and hands it over to the medical expert. The medical expert assess the condition of the patient like his heart rate, etc. and draws a suitable conclusion and instructs the technician who is locally available to the patient there and he takes the steps given by the doctor.The medical expert station has the IEEEaccess point.

Since the delay in any kind data in this design could be disastrous but at least by knowing the exact delay the medical expert could think accordingly in order to give the perfect assessment. So to calculate the delay the formula that is provided is

Delay=send time – receiving time.