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Analog vs digital technology?
The difference is how the messages are transmitted and the sound quality of those voice transmissions. Analog technology uses a system called Advanced Mobile Phone Service (AMPS). AMPS uses analog radio frequency modulation (FM) for voice transmission. Digital technology uses one of the following systems: CDMA, TDMA, or GSM. In general, digital transmissions provide for highly private conversations with superior sound quality to analog transmissions. TDMA, CDMA and GSM?
TDMA, or Time Division Multiple Access, sorts messages into time slots in order to send them. Voice and data are converted to digital signals that are sent and received in bursts in specific time slots. CDMA, or Code Division Multiple Access, was developed by Qualcomm for military antijamming systems, which translates into highly private conversations. It spreads a low power signal across a wide frequency width, which provides for a significant increase in subscriber capacity. GSM, or Global System for Mobile Communications, was originally developed in Europe and works similarly to the TDMA system: it sorts messages into time slots. The unique feature of this technology is that it allows for a short message service, up to 124 characters, while simultaneously carrying voice traffic. Cellular vs PCS service?
The main difference is the bandwidth on which the two services operate. PCS operates on a 1.9 GHz bandwidth, while Cellular providers use 800 MHz. Furthermore, the Cellular 800 MHz bandwidth supports analog transmissions, unlike the 1.9 GHz. In most cases, however, PCS carriers will license bandwidth from cellular providers so that they can provide a fall back analog service. Can I browse the Web on my telephone?
There are some phones with a built-in Web browser. This allows you to view text-only versions of web pages on your phones screen. It can be useful if you are looking for a stock quote, want to keep up with the latest news, sports scores, etc. Of course, the technology is brand new and will develop over time. What's the difference between text messaging and email services?
Email service is a type of text messaging. Many carriers will offer an email account that is something like yournumber@carriername.com. However, there are also other types of text messaging, such as operator assisted text messaging. This service allows someone to call in and leave a message with an operator who will then dispatch it in a textual format to your phone. The third type of text messaging is phone-to-phone text messaging. You can use your phone's keypad to send messages to other people on your network. You push "2" for "A" and push "2, 2" for "B", etc. The majority of the time, this type of text messaging is only available for people on similar networks. How does the two-way radio function work on a telephone?
The two-way radio function on a telephone is currently only available from Nextel. It uses Specialized Mobile Radio (SMR) to facilitate a one-to-many or many-to-one dispatch service. It is called the Nextel Direct Connect feature and is superior to a walkie-talkie because of its range. Converse with people up to 75 miles away with complete privacy. Are cell phones really dangerous?
Today's major medical studies have not shown any conclusive evidence that cell phones are dangerous to humans.
International Journal of Wireless Information NetworksEditor-in-Chief: Kaveh Pahlavan ISSN: 1068-9605 (print version)
ISSN: 1572-8129 (electronic version) Journal no. 10776 - Examines applications such as sensor and mobile ad-hoc networks, wireless personal area networks, wireless LANs, mobile data networks, etc.
- Features four categories of papers: invited openings, overview reports, technical papers, and letters
- Responds to the needs of researchers in the telecommunications and computer industries
The International Journal of Wireless Information Networks features high quality, original papers examining applications such as sensor and mobile ad-hoc networks, wireless personal area networks, wireless LANs, mobile data networks, location aware networks and services, and RF localization and RFID techniques. The journal also covers performance-predictions methodologies, radio propagation studies, modulation and coding, multiple access methods, security and privacy considerations, antenna and RF subsystems, VLSI and ASIC design, experimental trials, traffic and frequency management, and network signaling and architecture. Four categories of papers are published: invited openings reviewing current and future directions; overview reports addressing the philosophy and technical details of standards and field trials; technical papers presenting contributions of archival value; and letters enhancing and expanding upon published works. ABSTRACTED/INDEXED IN:SCOPUS, INSPEC, Google Scholar, EBSCO, Academic OneFile, Computer Science Index, Current Abstracts, DBLP, EI-Compendex, Gale, io-port.net, Library, Information Science & Technology Abstracts (LISTA), OCLC, SCImago, Summon by Serial Solutions, VINITI - Russian Academy of Science DOWNLOADS6 Jun 7 Jun 8 Jun 9 Jun 10 Jun 11 Jun 12 Jun Articles
| 48 | A Statistical Model for On-Body Dynamic ChannelsD’Errico, Raffaele; Ouvry, Laurent |
| 35 | Channel Models for Medical Implant CommunicationSayrafian-Pour, Kamran; Yang, Wen-Bin; Hagedorn, John Show all authors (6) |
| 30 | Improved Frequency Domain Channel Estimation and Equalization for MIMO Wireless CommunicationsZhang, Jian; Zheng, Yahong Rosa |
| 29 | Energy-Aware Georouting with Guaranteed Delivery in Wireless Sensor Networks with ObstaclesHamouda, Essia; Mitton, Nathalie; Pavkovic, Bogdan Show all authors (4) |
| 24 | WCDMA Uplink Capacity of a Long Tunnel Cigar-shaped Microcells for Underground Train ServiceTaha-Ahmed, Bazil; Calvo-Ramón, Miguel; Haro-Ariet, Leandro |
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