Cellular Essay (ameritech)

The orange is the home digital service area and the yellow is analog service area. Ameritech also offers free long distance all over the U.S.A. With a special package deal they have going right now. For sixty-five dollars a month you get 325 minutes per month. For their Chicago land service area it depends on which plan you pick, because the local rate per minute could either be .25 cents or .29 cents per minute for local calls that went over your minutes you received for free already. The price per minute also changes depending on if you are in the peak or off peak time slots. Peak hours are from 6 a.m. to 10 p.m. Monday through Friday. Off peak times are from 10:01 p.m. to 5:59 a.m. Monday through Friday. Saturday and Sunday are all day off peak and some holidays. Long distance runs from .25 cents per minute to .35 cents per minute. Depending on the distance it varies. If you leave your service area and enter another then roaming charges will be also added. If you decide to go with a cellular phone they have package deals that include a cell phone for a thirty five-dollar activation fee. They offer several packages to meet everyone's needs. You may also upgrade to a better phone, but then you must purchase that phone.

I contacted Ameritech and they told me that because I wasn't a business that they were unable to release that information. They then told me that they would get a hold of one of their managers and maybe they could give me this information. They took my name and number and I never received anymore information. I told them this was for a school project, but that didn't matter.

The PBX I chose was Meridian1 option 11c. This is a powerful PBX that comes in a small package. It supports 30 to 400 lines. Some other features are digital telephones, in building wireless communications, voice messaging, call center, PC-based system management, Ethernet connection, remote connection, keycode software activation, and multimedia applications. This PBX can be easily upgraded to new capabilities. Some of the programs that this PBX can run are Computer Telephony Integration (CTI), Customer Controlled Routing (CCR), and Integrated Voice Response (IVR).

Dual-tone multifrequency dial (DTMF) is a keypad containing 12 to 16 buttons. These are arranged in columns and rows. When the buttons are pushed they send two tones to the central exchange. The central exchange decodes the tones and rings the destination. A rotary phone or pulse dialing phone is sent over by clicks. The rotary dial contains two separate contacts. These contacts open and close for every digit. So if the number 3 were dialed, then the contacts would open and close 3 times. But a pulse dial will not pass through the central exchange. Which means that if a voice mail system answers you can not get through to the menu options. The number 8 tones are column 1336 Hz and row 852 Hz. For the central office to receive the tone it must be present for 40 ms and a pause of 60 ms between digits. For a rotary phone it takes 15 seconds to transmit 10 digits.

Carried Load: calls that are served, traffic that is carried to its destination

Offered load: arriving calls, calls attempting to enter a system

Blocked calls: traffic that can not be carried to its destination, blocked calls leave the system or overflow to another circuit

Blocked Calls-Cleared: upon receiving indication that all circuit are busy and can not be handled, the caller hangs up and is lost to the system.

Blocked Calls-Delayed: upon receiving indication that all circuits are busy, the caller waits and is held in the system until it can be processed.

First attempt traffic is a formula that Jacobsen developed to figure the percentage of people who retry their call immediately.

The Jacobsen retrial table assumes that 70% of the people retry immediately. Henry Jacobsen developed all of the retry tables. These tables help the server's figure out how many blocked calls that they receive. This allows them to figure if they need more lines or how many lines they will need in a certain area.

PCS: Personal communication service, transmit 1850-1910 MHz, receive 1930-1990 MHz

PCS 1900: Provided by time division multiple access or code division