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    • Types of Mobile Telephone Systems

      Types of Mobile Telephone Systems

      The main mobile telephone systems in the last twenty five years have been: YearMobile Telephone System 1981 Nordic Mobile Telephone (NMT) 1983 Advanced Mobile Phone System (AMPS) 1985 Total Access Communication Systems (TACS) 1986 Nordic Mobile Telephony (NMT) 1991 American Digital Cellular (ADC) 1991 Global System for Mobile Communication (GSM) 1992 Digital Cellular System (DCS)

    • Prepaid Cell Phones vs Contract Phones

      Prepaid Cell Phones vs Contract Phones

      Prepaid cell phones are mobile phones that are not associated with a long term contract and, therefore, do not incur the overage charges and late fees associate with contract plans. Prepaid cell phones are paid before the mobile service is activated on a monthly or “pay-as-you-go” basis and are deactivated when the service term expires

    • IMSI (International Mobile Subscriber Identity)

      IMSI (International Mobile Subscriber Identity)

      IMSI (International Mobile Subscriber identity) is the information that is used for identification of a mobile phone end-user on a network  and is uniquely associated with a given cell phone The IMSI code is stored as a 64 bit number or field, and is sent by the mobile phone to the cellular network. The code

    • SCM: Station Class Mark

      SCM: Station Class Mark

      The SCM (Station Class Mark) is a 4 bit number which holds three different pieces of information. Your cellular telephone transmits this information (and more) to the cell tower. Bit 1 of the SCM tells the cell tower whether your cellphone uses the older 666 channel cellular system, or the newer 832 channel cellular system.

    • IMEI (International Mobile Equipment Identity)

      IMEI (International Mobile Equipment Identity)

      Each GSM and UMTS mobile phone has a unique IMEI (International Mobile Equipment Identity) number. An IMEI number facilitates an important function – it easily identifies a mobile phone being used on a GSM (Global System for Mobile Communications) network. The IMEI is a useful tool to stop a stolen phone from accessing a network

    • How Video Conferencing Works

      How Video Conferencing Works

      Video conferencing has become popular over the last decade. Video conferencing is when two or more parties communicate in real time in separate locations with both video and audio signals. Technology Used in Video Conferencing Video conferencing works by using a few different technologies. Some of these technologies are hardware, others technologies involved in the

    • AMPS (EIA/TIA-553) and NAMPS (IS-91)

      AMPS (EIA/TIA-553) and NAMPS (IS-91)

      Mobile Frequency Range Rx: 869-894; Tx 824-849 Multiple Access Method FDM Duplex Method FDD Number of Channels 832 Channel Spacing 30kHz Modulation FM AMPS AMPS (Advanced Mobile Phone Service) was the first cellular mobile system in the United States. AMPS operates as an analog system using 30 kHz wide channels. NAMPS AMPS was later enhanced

    • 15 Ways to Improve Your Phone’s Battery Life

      15 Ways to Improve Your Phone’s Battery Life

      Although mobile phones have become almost ubiquitous in modern culture, device manufacturers have yet to solve the problem of significantly improving the battery life of mobile phones significantly. As a result, consumers must seek out methods to manage the overall application and program usage on their cell phones in order to improve the overall life

    • Cell Phone Frequencies

      Cell Phone Frequencies

      Cell phone frequencies are the frequency ranges within the Ultra High Frequency (UHF) band that are designated for cell phone use. Bluetooth devices, wireless networks, and television signals also use this frequency band. Although cellular phone systems divide cities and geographic areas into smaller cells of coverage, it allows for a fair amount of frequency

    • How Mobile Phones Are Dangerous to Health

      How Mobile Phones Are Dangerous to Health

      Since the number of cell phone users has continued to increase to more than six billion subscriptions at the turn of the decade, a common question that continues to get asked is how dangerous are mobile phones to one’s health? This question has continued to be asked over the past several decades since mobile phones

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