difference between balanced line and unbalanced line
This page on balanced line vs unbalanced line describes difference between balanced line and unbalanced transmission line types. Link to types and basics of transmission line is also mentioned.
A transmission line is a 2-wire cable which connects transmitter/receiver parts of wireless system with the antenna. The purpose of transmission line is to carry RF energy from one end to the other.
Usually antenna is located outdoor for best RF signal reception and equipments are located indoor to have protection against environmental factors such as rain, wind, dust etc.
There are two types of wire transmission line viz. balanced line and unbalanced line.
The figure-1 depicts balanced type of transmission line. Balanced line is constructed using two parallel conductors which are spaced about 1/2 inch to several inches. Insulating spacers are used to keep the wires separated. These spacers are made using ceramic or plastic materials.
The term "balanced line" means same amount of current flows in each wire with reference to ground. The direction of current in one wire is 180 degree out of phase with the current in the other wire. In balanced line, none of the wires are connected to the ground.
The figure-2 depicts unbalanced coaxial type of transmission line. In this type of unbalanced line, one conductor is connected to the ground.
As shown in the figure, coaxial cable (i.e. coax) consists of solid center conductor surrounded by plastic insulator(e.g. teflon). Over the insulator there is another conductor made of fine wires. At outer cover is made of plastic which protects the fine wire braid shield.
Coaxial cable is unbalanced line because current in center conductor is referenced to braid. The braid conductor is connected to the ground. Coaxial cables are available in various sizes starting from 1/4 inch to several inches.
Out of the two transmission line types, coaxial cable is widely used.
Transmission line, microstrip line and coaxial line
What is Difference between
difference between FDM and OFDM
Difference between SC-FDMA and OFDM
Difference between SISO and MIMO
Difference between TDD and FDD
Difference between 802.11 standards viz.11-a,11-b,11-g and 11-n
OFDM vs OFDMA
CDMA vs GSM
Bluetooth vs zigbee
Fixed wimax vs mobile
wibro vs mobile wimax
Microcontroller vs microprocessor