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A History of Technologies

1.1 Introduction

Radio or wireless–there must be a big difference; they are spelled a little different. I hate to disappoint and disillusion some of you who have counted so much on a ‘big difference’. However, just brace yourselves and prepare for the shock: there is absolutely no difference between radio and wireless except the spelling. Wireless does not mean sparks, noise, or a lot of switches. Wireless means communication without the use of wires other than the antenna, the ether, and ground taking the place of wires. Radio means exactly the same thing: it is the same process. Communications by wireless waves may consist of an SOS or other messages from a ship at sea or the communication may be simply the reception of today’s top 10 music artists, or connecting to the to check your email. It does not become something different in either spelling or meaning. Table 1.1 demonstrates a simple timeline of Wireless Technologies evolution.

1.2 Where it all began – Marconi

In February 1896, journeyed from Italy to England in order to show the British telegraph authorities what he had developed in the way of an operational wireless telegraph apparatus. His first British patent application was filed on June 2 of that year. Through the cooperation of Mr W.H. Preece, who was at that time the chief electrical engineer of the British Post-office Telegraphs, signals were sent in July 1896 over a distance of one-and-three-fourths miles on Salisbury Plain.

Wireless Data Technologies. Vern A. Dubendorf  2003 John Wiley & Sons, Ltd ISBN: 0-470-84949-5 2 A HISTORY OF WIRELESS TECHNOLOGIES

Table 1.1 A simple timeline in Wireless Technologies evolution (this is not to be considered an ‘all inclusive’ timeline)

1896 Guglielmo Marconi develops the first wireless telegraph system 1927 First commercial service operated between Britain and the US 1946 First car-based mobile telephone set up in St. Louis, using ‘push-to-talk’ technology 1948 publishes two benchmark papers on Information Theory, containing the basis for (source encoding) and error detection and correction (channel encoding) 1950 TD-2, the first terrestrial microwave system, installed to support 2400 telephone circuits 1950s Late in the decade, several ‘push-to-talk’ mobile systems established in big cities for CB-radio, taxis, police, etc. 1950s Late in the decade, the first paging access control equipment (PACE) paging systems established 1960s Early in the decade, the Improved Mobile Telephone System (IMTS) developed with simultaneous transmit and receive, more channels, and greater power 1962 The first communication satellite, Telstar, launched into orbit 1964 The International Satellite Consortium (INTELSAT) established, and in 1965 launches the Early Bird geostationary satellite 1968 Defense Advanced Research Projects Agency – US (DARPA) selected BBN to develop the Advanced Research Projects Agency Network (ARPANET), the father of the modern Internet 1970s emerges as an efficient means of data communications, with the X.25 standard emerging late in the decade WHERE IT ALL BEGAN – MARCONI 3

Table 1.1 (continued)

1977 The Advanced Mobile Phone System (AMPS), invented by Bell Labs, first installed in the US with geographic regions divided into ‘cells’ (i.e. cellular telephone) 1983 January 1, TCP/IP selected as the official protocol for the ARPANET, leading to rapid growth 1990 Motorola files FCC application for permission to launch 77 (revised down to 66) low earth orbit communication satellites, known as the Iridium System (element 77 is Iridium) 1992 One-millionth host connected to the Internet, with the size now approximately doubling every year 1993 Internet Protocol version 4 (IPv4) established for reliable transmission over the Internet in conjunction with the Transport Control Protocol (TCP) 1994–5 FCC licenses the Personal Communication Services (PCS) spectrum (1.7 to 2.3 GHz) for $7.7 billion 1998 Ericsson, IBM, Intel, Nokia, and Toshiba announce they will join to develop Bluetooth for wireless data exchange between handheld computers or cellular phones and stationary computers 1990s Late in the decade, Virtual Private Networks (VPNs) based on the Layer 2 Tunneling Protocol (L2TP) and IPSEC security techniques become available 2000 802.11(b)-based networks are in popular demand 2000–1 Wired Equivalent Privacy (WEP) Security is broken. The search for greater security for 802.11(x)-based networks increases

In March 1897, a greater distance of four miles on Salisbury Plain was cov- ered with wireless signals. On May 13 of that same year, communication was established between Lavernock Point and Brean Down England, at distance of eight miles. In America, during the period of 1890 to 1896, many students of science were in touch with the discoveries made in Europe during this period; but it was not until 1897 that the utilitarian American mind sensed the commercial possibilities of the advances being made abroad. 4 A HISTORY OF WIRELESS TECHNOLOGIES

In its March 1897 issue, McClure’s Magazine presented a long illustrated article entitled ‘Telegraphing Without Wires,’ by H.J.W. Dam, describing the experi- ments of Hertz, Dr Chunder Bose, and the youthful Marconi. Telegraph Age, New York, in its issues of November 1 and November 15, 1897, reprinted a long article from the London Electrician, entitled ‘Marconi Telegra- phy.’ This article consisted chiefly of the technical description that accompanied Marconi’s British patent specification number 12 039 of 1896. In September 1899, during the International Yacht Races held off of New York harbor, the steamer Ponce was equipped with radio devices by Marconi, for the purpose of transmitting reports on the progress of the race. Two receiving stations were equipped: one on the Commercial Cable Company’s cable ship Mackay Bennett, stationed near Sandy Hook, and connected with a land line station on shore by means of a regulation cable; the other at Navasink Highlands. This demonstration, even though it wasn’t very successful, immediately brought the subject to the front in the United States interest. In 1900, the erection of the first Marconi station at Cape Cod, Massachusetts, began. In March 1901, the Marconi Company installed radio devices at five stations on five islands of the Hawaiian group. For a long time these installations were to prove to be of little or no value due to the restricted availability scarcity of qualified operatives. During this same year, the Canadian government installed two stations in the Strait of Belle Isle; also constructed were the New York Herald stations at Nan- tucket, MA, and Nantucket light ship. The greatest radio event of 1901 was the reception by Dr Marconi at St Johns, Newfoundland, of what has become known as the famous letter ‘S’, transmitted as a test signal from his English station; this was on December 11, 1901. In 1904, several US government agencies, which included the Navy, the Depart- ment of Agriculture, and the Army’s Signal Corps, all began setting up their own radio transmitters, with little or no coordination between the various departments. In 1904, President Theodore Roosevelt appointed a board, which consisted of representatives from these agencies. This board was tasked with preparing rec- ommendations for coordination of governmental development of radio services. The 1904 ‘Roosevelt Board’ Report proposed assigning most of the oversight of government radio to the Navy Department and proposed imposing significant restrictions on commercial stations.

1.3 Packet Data

Packet Data technology was developed in the mid-1960s and was put into practical application in the ARPANET, which was established in 1969. Initiated in 1970, PACKET DATA 5 the ALOHANET, based at the University of Hawaii, was the first large-scale packet radio project. Amateur packet radio began in Montreal, Canada, in 1978 with the first trans- mission occurring on May 31. This was followed by the Vancouver Amateur Digital Communication Group (VADCG) development of a Terminal Con- troller (TNC) in 1980. The current TNC standard grew from a discussion in October of 1981 at a meeting of the Tucson Chapter of the IEEE Computer Society. A week later, six of the attendees gathered together and discussed the feasibility of developing a TNC that would be available to amateurs at a modest cost. The Tucson Amateur Packet Radio Corporation (TAPR) was formed from this project. On June 26 1982, Lyle Johnson and Den Connors initiated a packet contact with the first TAPR unit. The project progressed from these first prototype units to the TNC-1 and then finally to the TNC-2 which is now the basis for most packet operations worldwide. Packet has three great advantages over other digital modes: transparency, error correction, and automatic control. The operation of a packet station is transparent to the end user. Connect to the other station, type in your message, and it is sent automatically. The Termi- nal Node Controller (TNC) automatically divides the message into packets, keys the transmitter, and then sends the packets. While receiving packets, the TNC automatically decodes, checks for errors, and displays the received messages. Packet radio provides error-free communications due to the built-in error detec- tion schemes. If a packet is received, it is checked for errors and will be displayed only if it is correct. In addition, any packet TNC can be used as a packet relay station, sometimes called a digipeater. This allows for greater range by stringing several packet stations together. Users can connect to their friends’ TNCs at any time they wish, to see if they are at home. Another advantage of packet over other modes is the ability for many users to be able to use the same frequency channel simultaneously. Since packet radio is most commonly used at the higher radio frequencies (VHF), the range of the transmission is somewhat limited. Generally, transmis- sion range is limited to ‘unobstructed line-of-sight’ plus approximately 10–15% additional distance. The transmission range is influenced by the transmitter power and the type and location of the antenna, as well as the actual frequency used and the length of the antenna feed line (the cable connecting the radio to the antenna). Another factor influencing the transmission range is the existence of obstruc- tions (hills, groups of buildings, etc.). Connections made in the 144–148 Mhz range could be 10 to 100 miles, depending on the specific combination of the variables mentioned above. 6 A HISTORY OF WIRELESS TECHNOLOGIES

1.4 Voice Technologies

In the November 7, 1920 issue of the Boston Sunday Post there was an article authored by John T. Brady covering the topic of ‘Talking by Wireless as You Travel by Train or Motor,’ which noted ‘It is now possible for a business man to talk with his office from a moving vehicle.’ This was a review of two-way radio conversation tested by Mr Brady and with Harold J. Power who was then the head of the American Radio and Research Corporation, while Power was in a moving automobile. It would not be until the 1980s that the technology needed for such things as and wireless telephones would be perfected to the point that they became widely available consumer products. Although the telephone’s use for individual communication largely overshadowed applications for distributing entertainment and news, the reverse would be true for radio, with broadcasting dominating for decades, before radio transmissions would be significantly developed for personal, mobile communication.

1.5 Cellular Technologies

In cellular networks there are radio ports with antennas that connect to base stations (BSs) that serve the user equipment known as mobile stations (MSs). The communication that takes place from the MS to the BS is knows as the uplink while the communication from the BS to the MS is known as the down- link. The downlink is contentionless, however several MSs access the uplink simultaneously. This uplink uses a very important characteristic, which is the multiple-access technique. Frequency-division multiple access (FDMA), time-division multiple access (TDMA) and code-division multiple access (CDMA) are the most widely used physical-layer multiple access techniques in use today. The infrastructures of cellular networks include mobile switching centers (MSCs). These control one or more BSs and provide the interface for them to the wired public switched telephone network (PSTN), a central home location register (HLR) and the visiting location register (VLR) for each MSC. The VLR and HLR are databases that keep the registered and current locations of MSs to be used in the handoffs. Handoff is the process of handing a call from one cell to a new cell as the MS moves around.