Difference between coaxial line and waveguide

	Coaxial Cable	Wave-guide
1.	It consists of center conductor and outer conductor.	Waveguide consists of single metallic walls acting as conductor. There is no center conductor in the waveguide.
2.	The fundamental or dominant mode wave in a coaxial line is TEM.	TEM wave can not propagate through it. Wave transmission takes place using TE or TM modes.
3.	There is no concept of cutoff frequency.	Each waveguide has a finite cut-off frequency.
4.	The coaxial lines have PTFE as di-electric and have relatively higher loss.	As waveguide is air filled there will be less loss compare to coaxial line.
5.	The power handling ability of coaxial-cable is relatively lesser.	Waveguide can handle higher power compared to coaxial cable because waveguide is filled with air as dielectric and air has higher break down voltage.
6.	The bandwidth of coaxial line is broad.	The bandwidth of waveguide is smaller.