What is Cellular Network?

Cellular network also known as mobile network is a telecommunication network where the link to and from end nodes is wireless. The cellular network is distributed over land areas known as cells, each cell be in service of at least one Fixed Transceiver (is an electronic device which is a combination of a radio transmitter and a receiver) also known as Mobile Tower. The base station provides the cell with coverage which is used for transmission of voice, data, video, calls, and many more.
As the increase in capacity of cellular network, with compared with a network with a single transmitter, for mobile communication switching system which is developed by Amos Edward Joel Jr. of Bell Labs that enables multiple callers in a given area to use the same frequency by switching calls with the nearest available cellular tower which have that same frequency available. This method of cellular signal is not safe as a given radio frequency can be reused in different area for a discrete transmission. As there is some level of interference in signal from other cellular devices which uses same frequency. To overcome this interference of signal there must be at least one cell gap between cells which reuse the same frequency in std. format FDMA (Frequency Division Multiple Access)

Frequency Reuse

The key characteristic of a cellular network is the ability to re-use frequencies to increase both coverage and capacity. adjacent cells may be run on different frequencies, however, there is no problem with two cells sufficiently far apart operating on the same frequency, provided the masts and cellular network users equipment do not transmit with too much power. The cellular network haves a coverage in a circular form which ranges from 1km to 30km i.e., 0.62miles to 18.64miles.
If you wise to calculate the element which determine the frequency reuse that are reuse distance and the reuse factor as ;
R=Cell radius
N=Number of cells per cluster

Mobile phone network

The mobile phone network is most common example of cellular network. It is a portable device which receives or makes calls through a cell site or transmitting tower. A cellular network is used by the mobile phone operator to reach both coverage and capacity for the users. The all cell sites are connected to telephone exchange or central office, which in turn connect to the Public Switched Telephone Network(PSTN).
The different types of digital cellular technologies includes;
  1. GSM (Global System for Mobile Communication)
  2. CDMA(Code-division Multiple Access)
  3. AMPS(Advanced Mobile Phone System)
  4. EDGE(Enhanced Data Rates for GSM Evolution)
  5. UTMS(Universal Mobile Telecommunications System)
  6. DECT(Digital Enhanced Cordless Telecommunications)
  7. LTE(Long Term Evolution)

Assembly of the mobile phone cellular network 

A mobile phone cellular network consists of following structure
  1. A network of radio base station forming the base station subsystem.
  2. The core circuit switched network for managing voice calls and text on cellular network.
  3. A packet switched network for handling mobile data.
  4. The public switched telephone network to connect subscribers to the wider telephony network.
Any cellular device uses a mobile data to connect that network via an RBS (Radio Base Station) with corresponding cell which connects to MSC (Mobile Switching Center). MSC provides a connection to a PSTN (Public Switched Telephone Network). The uplink and downlink from a phone is transfer through RBS.

Radio channels effectively uses transmission medium through the use of the following multiplexing and access points:
  1. Frequency-Division Multiple Access (FDMA)
  2. Time-Division Multiple Access (TDMA)
  3. Code-Division Multiple Access (CDMA)
  4. Space-Division Multiple Access (SDMA)

Cellular frequencies

Cellular frequencies are the sets of frequency that ranges between the ultra high frequency band that have been appointed for cellular compatible mobile devices to connect with cellular network. The effect of cellular frequency on cell coverage means that different frequencies serve better for different uses. Such as Low frequencies like 450 MHz NMT that be in the service very well for countryside coverage, 900MHz suites well for light urban coverage. Higher frequencies gives fast cellular speed but has disadvantage when it comes to coverage,
Here are some Example of the coverage area of one cell on the frequency shown in table below
Frequency (MHz) Cell radius (km) Cell area (km2) Relative cell count
450 48.9 7521 1
950 26.9 2269 3.3
1800 14.0 618 12.2