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    • IS-54 and IS-136: TDMA

      IS-54 and IS-136: TDMA

      IS-54 and IS-136 are standards for TDMA American Digital Cellular. Mobile Frequency Range Rx: 869-894; Tx: 824-849 Multiple Access Method TDMA/FDM Duplex Method FDD Number of Channels 832 (3 users per channel) Channel Spacing 30Khz Modulation DQPSK Channel Bit Rate 48.6Kb IS-54 and IS-136: TDMA Security IS-54 and IS-136 use the CAVE (Cellular Authentication, Voice

    • 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.

    • How to Defeat Caller-ID Blocking

      How to Defeat Caller-ID Blocking

      One trick to defeat Caller-ID blocking is to forward your phone line to a friend who lives in another LATA. When your friend receives the anonymous phone call, have him use *69 Call Return to dial to offending party back. As he is now placing a long distance phone call, the telephone number of the

    • SIM Card

      SIM Card

      A SIM (Subscriber Identity Module) card is a type of interface card that is found in most modern cell phones and contains the user’s account information as well as some types of media, such as contacts, pictures, and sometimes ringtones. A SIM card contains an ICCID, or Integrated Circuit Card ID, number that identifies the

    • Mobile Software

      Mobile Software

      Mobile software refers to software that can be stored and executed on a mobile device such as a cell phone, PDA, smart phone, or similar device. Mobile software can range in its capabilities as some simply change the virtual appearance of the device while others provide important features such as menu layouts and password protection.

    • Forward and Reverse Channels

      Forward and Reverse Channels

      Forward and reverse channels refer to a number of frequencies that are used by a telecommunications broadcast system in order for a telephone tower and a cellular telephone to communicate with each other. A forward channel refers to the frequencies used by a telephone tower to communicate with all nearby cellular phones. Contrastingly, a reverse

    • PCS (Personal Communications Service)

      PCS (Personal Communications Service)

      PCS (Personal Communications Service) is a set of standards. Most PCS standards are based on an existing standard. PCS is little more than the operation of these standards on the frequency bands of 1930-1990MHz for receiving and 1850-1910Mhz for transmitting. PCS StandardBase Standard PCS TDMA IS-136 PCS CDMA IS-95 PCS 1900 GSM PACS PHS cordless

    • Who Invented the Cell Phone?

      Who Invented the Cell Phone?

      Dr. Martin Cooper is the person credited with both inventing the modern cell phone as well as making the first cell phone call in New York City, New York in April 1973. A related invention is the cave radio phone invented by Nathan Stubblefield who was awarded a patent for the idea in the early

    • Smartphone

      Smartphone

      A smartphone is a mobile phone with a considerably greater amount of functionality than an ordinary mobile phone or a feature phone. Smartphones can be considered a blend between a mobile phone and a full featured mobile computer, similar to the PDAs (Personal Digital Assistants) of the past, but even more capable. They typically include

    • What is SMS (Short Message Service)?

      What is SMS (Short Message Service)?

      SMS, or Short Messaging Service, is a text-based messaging service that is used by over 2.4 billion mobile phone users worldwide. SMS allows users to send and receive text-based messages, pictures, videos, and audio clips from other mobile phone users and desktop computer users who have applications that can interact with mobile phones. SMS differs

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