I would like to greet Malcolm for his explanations. Assume that we have a dipole antenna which stands vertically and is fed from the mid point. Then the electric field will be always in the vertical direction parallel to the dipole while the magnetic field lines is circulating the antenna. The radiation pattern is like a closed circular tube surrounding the antenna. So the height of the tube will be the range of the existence of the the E-field and the length of the arc will be the range of the existence of the magnetic field. Where an electric field exists, there will be a magnetic field perpendicular to it and both are perpendicular to the propagation direction in space.

When you put a receiving antenna you have to put it vertical since the the magnetic field is vertical. It is said that the antenna is vertically polarized.

In this way the magnetic field flux will be circular and perpendicular to it so it will induce an emf in it. If you put the receiving antenna horizontally no emf will be induced in it since it is perpendicular to the electric field.

You must imagine that the antenna is like a lamp positioned in its feed point. But the filament is not a point but a short line.

Best wishes

Hi Parisa, Please follow the following two links. Useful info is given about ur query.

1. https://www.researchgate.net/post/What_is_meant_by_E-plane_and_H-plane

2. https://www.researchgate.net/post/How_to_check_E-Plane_H-plane_radiation_patterns_in_HFSS

Hope this helps...

Dear Parisa

If you have to design your antenna structure in xy-plane in CST Microwave Studio (direction of propagation is z-direction) then, for xz-plane (phi = 0 degree) you can find the H-field Co-polarized component (E_phi) and Cross-polarized component (E_theta).

Similarly, for yz-plane (phi = 90 degree) you can find the E-field co-polarized component (E_theta) and cross-polarized component (E_phi).

In CST MWS--->go to far-field tab--->consider theta and phi component. In both cases, the angle theta is varying and phi is constant value (either 0 degree or 90 degree).

Hope you find answer.

When your antenna has linear polarization the direction of the E field defines the E-plane. The H plane is at 90 degrees to this. If the polarization is vertical then the E-plane is an elevation cut, and the H-plane is an azimuth cut.

For waveguide antennas the sidelobes are often higher in the E-plane and lower in the H-plane because of the way the electric field has to fall to zero next to the waveguide walls in the H-plane but not in the E-plane.

Electric dipoles are omnidirectional in the H-plane but not in the E-plane.

Magnetic dipoles are omnidirectional in the E-plane, not in the H-plane.

If your antenna is not linearly polarized then the E-plane and H-plane do not exist.

Dear Parisa Keihani

The answer of your question is so simple, but you need to know some background knowledge in antenna and its associated parameters:

As you know the antenna acts as an intervening structure to radiate ( in transmit-mode) or to receive ( in Receive-mode) the electromagnetic energy to/from the surrounding space, i.e. the Air. Imagine a theoretical "Point" antenna in space. As yo may know, this antenna will radiate equally in any arbitrary direction, and we call it an Isotropic antenna. the radiation pattern of iso-antenna is a sphere.

lets assume yo know the direction of variation of electrical and magnetic field in that sphere. they will be two plate perpendicular to each other. can you imagine the projection of the radiation pattern on these plates? they are two circles. one of the is the E-plane and other is the H-plane radiation pattern.

I Hope you find it useful

do not hesitate to answer any questions

Best regards

Ahmad

E-plane contain the maximum amount of electric field whereas H-plane contain the max amount of magnetic field. Therefore, these two are the co-pol planes which can be used to design an antenna efficiently.

S11 can be found for resonator/filter/oscillator etc microwave devices whereas E-plane and H-planes can be found for an antenna. Without the proper knowledge of those planes, we say that it is an antenna.

Hello. There are tangential components of electric and magnetic fields in the aperture of the antenna. The E-plane is associated with the tangential component of the electric field, and the H-plane is associated with the tangential magnetic component of the field in the aperture of the antenna.

E-plane means direction of electric field plus direction of propagation and H-plane means direction of Magnetic field plus direction of propagation.

Dear Krunal, this observation is not correct according to P=ExH (poynting theorem). Direction of propagation is the direction of power flow, not E or H flow. The definitions as given above is correct. I do use those definitions to obtain E and H plane theoretically.

Krunal The E-plane is usually the plane containing the E field vector and the forward direction (the direction that you say the antenna is pointing for this plot). For all antennas, only some of the energy propagates in the forward direction, there is no one direction of propagation, energy propagates in all directions contained in the polar diagram.

As suggested by others E-plane is the plane containing maximum E-feild vector along the plane and H-plane is the plane containing maximum H-feild vector along the plane. Attached image can give us clarity.

In the figure top left H-plane horn because H-field is maximum along horizontal direction so it is H-plane. In this case magnetic field will be horizontal side.

In the figure bottom left E-plane horn because E-field is maximum along vertical direction so it is E-plane. In this case electric field will be vertical side.

Sudipta Maity Sir, Since we are defining a plane , only orientation of Electric or Magnetic field can not be used to define E or H-plane. Always we have to consider the direction of power flow i.e. forward direction that is governed by Pointing Vector. Since E and H fields both are perpendicular to propagation direction, only presence of these field at a particular point defines the direction of propagation.

Hello all,

I really thank you for taking your time to help me. I want to know what is difference between two antenna if have same E-plane but their H-plane is different? it means why do antenna engineers report H-plane? and why H-filed pattern is important. For instance, in some antenna books writers mention that H-filed of antenna A is narrow than H-filed of antenna B. what does it mean? Is it bad to have narrow or wide H-filed pattern for example based on this picture?

If their E-plane is the same then the width and flare length in the E-plane is the same. If the H plane is different then the width and/or flare in the H-plane is different.

People want different beam-widths for different purposes. The E-plane is often the vertical beamwidth, which is usually narrow so energy is not wasted into the air or into the ground, but the H-plane is horizontal so the beam may be wide or narrow depending on whether the antenna is supposed to have a narrow beam to talk to one other antenna or to see/transmit over a wide angle.

The antenna radiates electromagnetic waves in the surrounding space. This electromagnetic wave in space is transverse electromagnetic wave TEM where the electric field vector is perpendicular to the magnetic field vector and both are perpendicular to the direction of propagation. So, the E-plane hosts the electric field vector and the H plane hosts the H- vector.

The importance of these planes is their role in the radiation pattern where one determines the intensity of the EM radiation in the E -plane and in the H-plane.

Best wishes

Dear Prof. Malcolm White and Prof. Abdelhalim Zekry

I am really appreciative of your response and explanation and sorry for delay in response.

As a matter of fact I can't find the role of H-plane diagram. I am familiar with how to define E-plane and H-plane via calculating and using antenna equation in different phi and theta but the effect of H-plane is unknown to me.

I know that electromagnetic waves E and H fields are source of each other based on Max-well equation but in the real wold, I can't distinguished the pros and cons of narrow and wide H-plane diagram. Because in every references that I have ever seen they focus on E-filed and explain the antenna's operation based on E-filed.

Sorry that I am a little bit confused.

In the far field (at a distance twice [the square of the antenna width] divided by the wavelength) the ratio of electric field to magnetic field is 377 ohms in all parts of the polar diagram, and the electric field and the magnetic field are always at right-angles to each other, and both are at right angles to the radius going back to the antenna.

Because E and H are at right angles to each other and to the radius, and in the cardinal planes, usually have the same directions as the E-field and the H field in the aperture, these directions can be used instead of x and y or theta and phi or phi and z to describe axis directions. This is all that it means when it says E-plane and H-plane.

I would like to greet Malcolm for his explanations. Assume that we have a dipole antenna which stands vertically and is fed from the mid point. Then the electric field will be always in the vertical direction parallel to the dipole while the magnetic field lines is circulating the antenna. The radiation pattern is like a closed circular tube surrounding the antenna. So the height of the tube will be the range of the existence of the the E-field and the length of the arc will be the range of the existence of the magnetic field. Where an electric field exists, there will be a magnetic field perpendicular to it and both are perpendicular to the propagation direction in space.

When you put a receiving antenna you have to put it vertical since the the magnetic field is vertical. It is said that the antenna is vertically polarized.

In this way the magnetic field flux will be circular and perpendicular to it so it will induce an emf in it. If you put the receiving antenna horizontally no emf will be induced in it since it is perpendicular to the electric field.

You must imagine that the antenna is like a lamp positioned in its feed point. But the filament is not a point but a short line.

Best wishes

Variation of Electric and Magnetic field patterns confined to particular plane of geometry.

generally electric field becomes more at open end (where voltage becomes maximum) and magnetic field near to ground side (where current becomes maximum). Now for dipole antenna vertical plane (parallel to dipole antenna) is electric strength is more thus e-plane and horizontal plane ( orthogonal to vertical plane and circular in nature) is h-plane

Can E plane and H plane be same for an antenna

Yes, it is possible. But, most of time at fundamental mode of a microstrip antenna or a DRA, E-plane (phi = 0 deg) is little bit wider than H-plane (phi = 90 deg). In that case, the antenna is placed on x-y surface and the height of the antenna is along the z-axis.

Sudipta Maity thank you for answering. Yes E-Plane (phi =0degree) is wider than the H plane (phi = 90 degrees) but is there any advantage of having them same?

You choose your beamwidths to do what the antenna is supposed to do. If the beamwidth is too narrow it won't work in directions you want it to and if it is too wide it will have less gain in the directions you want than it could have had. For many antennas, having equal beamwidths in the two planes is of no value.

Lets consider x,y and z axis. Lets assume that the z is the direction of electromagnetic propagation , x is the electric component and y is the magnetic component. Now with respect to x (electric component ) axis the x-z is defined as E plane. Like wise with respect to y axis(magnetic component) axis , y-axis is defined as H plane. E Plane is also called azimuth and H plane is called as elevation. The E Plane is changed from 0 degree to 360 degree and H plane is changed from -90 degree to + 90 degree. Actually this is the method to define how an antenna must behave while transmitting or receiving. the basic concept is to see how an antenna behaves in a sphere when it is Omni directional. When the antenna is directional, the pattern becomes restrictive to particular direction and we say E plane and H plane patterns have changed. For a simple understanding consider a dish antenna on the top of roof for DTH services. We can rotate it 360 degree in elevation and 180 degree in azimuth . With this rotation the complete possibility to cover the antenna range is complete. Hence the purpose of E plane and H plane is a concept assumption to understand the behavior of antenna. The behavior of E plane and H plane w r t each other decide the polarization isolation. When the antenna is placed in such a way that its electric component is vertical to the electric component of earth (far field assumption), it is called vertical polarization and if the electric component is horizontal to earth electric component it is horizontal polarised. As Malcolm bought out, if the beam width of antenna is equal for both E and H, the polarisation isolation (which must be greater to 10dB), will be zero and significance of polarisation vanish which is not possible

In a specific case, we may get same E plane and H plane, I did not get it. But, I think, 1st TM mode of a DRA ( rectangular and equilateral trinagle may be, not sure) is same as per I can remember. This is theoretical data obtained from cavity model approximation.

In practice, we give excitation. Most of the time, we prwfer to give coaxial probe. Hence the symmetry of the geometry disturbed w.r.t. electron and magnetic field. Hence, we do not get same E plane H plane in practice.

If we get same bemwidth for E plane and H plane in practice, it will be helpful and can be used for mobile signal transmission. If the region have uniform population density, all user will get same amount of signal.

The mobile industry will prefer it always.

In my earlier ( just previous) post, I told that in practice we will never get same E and H plane

I think, slanted polarization (45 deg polarization) shows same E plane and H plane theoretically.

Due to coaxial probe excitation ( or other excitation), we never get same beamwidth in orthogonal planes.

For the same reason, CP does not show same beam with in two orthogonal planes.

E plane means the (XOZ) plane or else ϕ = 0°

H plane means the (YOZ) plane or else ϕ = 90°

E plane and H planes are corresponding to phi = 0 and 90 deg respectively, is not correct all time. We can give patterns at phi =0 and 90 deg, but we can't say those are E and H planes respectively.

Can you explain more (Sudipta Maity). when we can find the E plane does not correspond to 0 ° and also the H plane does not correspond to 90 °?

thank you

For any antenna having tilted beam patterns, we will get E-plane and H-plane at other planes (not at phi = 0 and phi = 90 deg planes). Same thing is also valid for antenna having perturbed geometry

But, to understand the results (or re-generation), we need standardization. Hence, we prefer to provide patterns at phi = 0 (xoz plane) and phi = 90 (yoz) planes. We do not mention E-plane and H-planes.

From HFSS 'compute antenna parameters' option, we can find the orientation at which E-field is maximum. That will be E-plane and the orthogonal one is H-plane.

I agree with Dr. Maity's Response. If the beam is tilted in one plane like the case of one dimensional Leaky wave antenna, The patterns should be like XZ- YZ plane rather should not be called as Purely E Plane and H palne Pattern.

Mr. Maity , Mr. Majumder,

according to your answers, and if we reread the content of this article '' Asymmetric Half-Bowtie Antennas with Tilted

Beam Patterns ''. The E plane and the H plane for this work don't present the XZ plane and the YZ plane, respectively?

thanks

Yes, as it is ' Asymmetric ', we may not get the E plane and the H plane at phi = 0 and phi = 90 deg respectively.

It would be better if you consult Antenna Theory by Balanis (1982/1996) and ( E A Wolff, 1965). Lots of examples are there where E and H planes are not corresponding to phi = 0 and phi = 90 deg.