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CIS 513
Assignment One
Unicode & Frequency Hopping Spread Spectrum (FHSS)

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Abstract
Unicode provides a standardized means for text in nearly any language to be shared across the Internet.
Frequency Hopping Spread Spectrum is a means by which transmissions “hop” between a variety of frequencies, lessening the transmission’s vulnerability to outside sources.
Assignment One
Unicode
Our world is increasingly shrinking as new technologies are bringing people and their cultures in closer contact with each other. Two technologies that are helping make this happen are wireless computing in all its various forms and Unicode. To understand how important Unicode is to the future of the Internet and computing, first we need to understand why Unicode was developed. Its main predecessor, the American Standard Code for Information Interchange (ACSII), which is “stored as 1 byte (8 bits) in binary code.” (Olenewa, J. & Ciampa; M. (2007) However, “one of the limitations of ASCII is that there are not enough codes for all the symbols used by foreign languages.” (Olenewa, J. & Ciampa, M.; 2007) Additionally, ACSII is only useful for up to 128 different codes. Unicode breaks this barrier by using 2 bytes (16 bits) in order to represent nearly all of the languages of the world. From this it’s not too much of a leap to see that using Unicode is useful to global businesses in a variety of ways. As these global businesses become more mobile, relying on wireless technologies to do business, some of the top benefits of Unicode are, “Text in any language can be exchanged worldwide” meaning that it “Eliminates data corruption and other problems due to incompatible pages of missing conversion tables.” (Texin, T., 2003) “Widespread industry support provides platform and vendor independence” (Texin, T., 2003) allows cross-operating systems (OSs) to freely exchange information without concern that the languages exchanged may not be compatible with a different OS. And the last major benefit for global companies is that Unicode “allows for multilingual text using any or all languages you desire.” (Texin, T., 2003) An example of this is that “invoice or ticketing applications can print customer information in their native languages from a single database.” (Texin, T., 2003) These three benefits and examples are just the beginning of what global businesses are looking for to successfully compete. Perhaps a simpler way to express why Unicode is a good thing for globalization can be found in Richard Cook’s “Unicode gives people what they want.” The five words, “data, easy, find, give, keep” (Cook, R., 2001) express this idea neatly. “Data” means they want all sorts of useful information. “Easy” it should be inexpensive. “Find” means it should be accessible. “Give” means the transfer of data that can be easily swapped. And “keep” means that the information should be available for a very long time and that once bought it should not have to be reacquired. He says it best, “Unicode support is a modest long term investment that will have big future payoffs. Building Unicode support opens and keeps open doors to rich data.” (Cook, R., 2001) What does this all have to do with a wireless environment? Looking at Mr. Cook’s five words another way, Unicode facilitates access to any information anywhere in the world in nearly any language in an easy and affordable manner. This is exactly what businesses crave not only for their employees but also for the customers that frequent these global enterprises.
Frequency Hopping Spread Spectrum (FHSS) One alternative to narrow band radio frequency (RF) transmissions is spread spectrum transmissions. Narrow band RF means that transmission and reception occurs on only one specific frequency. This is a simple method, but is “vulnerable to outside interference from another signal.” (Olenewa, J. & Ciampa, M.; 2007) Frequency Hopping Spread Spectrum (FHSS) is the one method by which spread spectrum can be achieved. “With FHSS, a short burst is transmitted at one frequency and then a short burst is transmitted at another frequency, and so on until the transmission is completed.” (Olenewa, J. & Ciampa, M.; 2007) FHSS has two main disadvantages in comparison to Direct Sequence Spread Spectrum (DSSS), another method of spread spectrum: “Greater tolerance of signal interference because of operation over wider (83.5 MHz) bandwidth, and Capability to operate up to 10 collocated access points without significant interference.” (Geier, J.; 2000) FHSS also has three main disadvantages to DSSS: “Lowers potential data rates from individual physical layers, Less range than direct sequence because of need for at least 18dB SNR at receiver, and Potential obsolescence as more companies continue to favor the higher-speed (802.11b) direct sequence products.” (Geier, J.; 2000) These disadvantages not-withstanding, many commercial applications use FHSS, including cordless phones and multi-handset units for small business. (Olenewa, J. & Ciampa, M.; 2007) Bluetooth (IEEE Standard 802.15.1-2002) also uses FHSS. Although not strictly FHSS, one military application that is similar to FHSS, is the AN/WSC-3(V)11 transceiver. Also known as the Have Quick transceiver, it operates in a frequency hopping method that is very similar to FHSS.
References
Olenewa, J. & Ciampa, M. (2007). Wireless# Guide to Wireless Communications. Boston: Thompson Course Technology
Texin, T. (2003-11-10). “Benefits of the Unicode Standard” retrieved 7:19 P.M. JST on 14 July 2010 from http://www.i18nguy.com/UnicodeBenefits.html
Cook, R. (March 9, 2001). “Unicode gives people what they want” retrieved 7:29 P.M. JST 14 July 2010 from http://linguistics.berkeley.edu/~rscook/html/UnicodeGives.html
Geier, J. (Nov 29, 2000). “IEEE 802.11 Standard Overview > IEEE 802.11 Frequency Hopping Spread Spectrum (FHSS)” retrieved at 8:06 P.M. 14 July 2010 from http://www.informit.com/articles/article.aspx?p=19825&seqNum=4