Ib qhov tsis muaj qhov nruab nrab yog qhov nruab nrab nrog xoom conductivity thiab finite permeability thiab permittivity. Thaum lub electromagnetic yoj propagates los ntawm ib tug lossless nruab nrab, lub amplitude ntawm nws hluav taws xob teb los yog magnetic teb tseem nyob tas mus li thoob plaws hauv lub propagation.
Rau qhov nruab nrab qhov attenuation tas li yog xoom?
Kev piav qhia: Lub attenuation yog qhov poob ntawm lub zog ntawm nthwv dej thaum nws nthuav tawm. Nyob rau hauv ib qho tsis muaj dielectric, qhov poob ntawm lub zog yuav tsis tshwm sim. Yog li qhov attenuation yuav yog xoom.
Dab tsi yog qhov kev sib raug zoo ntawm theem tshaj tawm thiab qhov chaw dawb tshaj tawm hauv qhov nruab nrab tsis muaj dielectric?
Phase tshaj tawm yog qhov siab tshaj plaws (=c) hauv qhov chaw dawb, thiab qeeb los ntawm qhov ua tau ntawm 1 / √μrϵr hauv lwm qhov nruab nrab tsis poob.
Yuav ua li cas yog qhov tseeb yoj kab zauv rau hluav taws xob teb rau cov xov xwm lossless?
Rau qhov zoo meej lossis tsis muaj dielectric cov khoom tau muab raws li, σ=0, є=єo єr thiab µ=µo µr. Nyob rau hauv ob qho tib si dawb qhov chaw nruab nrab thiab lossless dielectric nruab nrab σ=0, yog li kev tsom xam ntawm nthwv dej propagation yog zoo sib xws nyob rau hauv ob qho tib si.
Plane Waves in Lossless Medium
