The half power beam width represents the angle within the main lobe of the antenna where its gain is above 50% of the peak gain (angle between -3dB points of the main lobe). First null beam width (B fn)

A helical antenna in a normal configuration has a high impedance of 140 ohms. Ideally this should be reduced close to 50 ohm to minimize the mismatch loss between the helix and the coaxial connector and cable. One simple way this can be done is by deforming a portion of the first turn so that its pitch gradually changes, from almost parallel to the reflector to the nominal pitch of the rest of the helix. Helix Length Calculator Radius of Helix (in cm): Pitch of Helix (in cm): Calculate Length of Helix (in cm): Introduction: This tells you which diameter to aim for when selecting your conductor to make the helix. As has been proven by many people though, it is not a critical design restriction, especially when using conductor thinner than recommended. Reflector diameter (R min and R max) Same as S λ, except calculated for the current wavelength. This value together with diameter D are the two important measurements for constructing your helical antenna. Half power beam width (B hp) To calculate the length of a helical antenna, multiply the circumference of the helix by the wavelength of the signal. Divide the result by 4 times π. What is a Helical Antenna?Coil diameter (Dc) is the diameter measured from the center of the coil to the neutral circle (the circle right between the inner and outer circles). Self-explanatory; F defines the frequency in MHz that the helix should operate at. At lower frequencies (below ~500 MHz), antennas such as the cross-dipole/cross-yagi are usually preferred for circular polarization due to the large scale of the helical antenna at those wavelengths. At high microwave frequencies (above ~3000 MHz), linear waveguide antennas and dish feeds with depolarizers become more convenient for DIY projects. Of course, when proper thought and care is given to the construction, helical antennas can work even outside of this range just fine, and in fact have been used in practice by amateurs and professionals alike (for example large helicals for the 2m ham band, or tiny ones for 5 GHz WiFi or drone/FPV use). Turn spacing (S λ) h: Represents the vertical distance covered by the helix in one complete cycle, also measured in any unit of length.

The helix is not just a curve in 3-dimensional space, but a fundamental shape in higher dimensions too, with applications in advanced mathematical physics.A Helix Length Calculator is a tool that calculates the length of a helix based on the rise of the helix in one revolution and the circumference of the helix. A helix is a three-dimensional shape that looks like a spiral, such as a spring or a corkscrew. The helix calculator can be useful in a variety of fields, such as engineering, biology, and architecture. For example, in engineering, the helix length formula can be used to design screws, bolts, and other types of fasteners. In biology, the formula can be used to study the structure of DNA, which has a double helix structure. In architecture, the formula can be used to design spiral staircases, which are a popular feature in many buildings. Conclusion: Length (L). The total length of the wire used to create the coil. Below is the coil length formula: Depending on the way the helical conductor is wound, the resulting antenna will be either right-hand circularly polarized (RHCP) or left-hand circularly polarized (LHCP). A RHCP antenna will not be able to receive LHCP signals, while a LHCP antenna fails to receive RHCP. This is because of a theoretical infinite dB mismatch loss between RHCP and LHCP, although in the real world - where no antenna is perfect - even a RHCP helix will come with a (highly suppressed) LHCP component.

Helix Length Calculators can be useful in a variety of applications, such as in engineering, architecture, and design. For example, a Helix Length Calculator can be used to determine the length of a spiral staircase or the length of a spring for a particular application. A helical antenna is a specialized type of antenna that is designed to radiate and receive electromagnetic waves in circular or elliptical polarization. It is constructed by winding a wire in the shape of a helix or spring around a cylindrical or conical form. The key parameters of a helical antenna are the diameter and pitch of the helix, the number of turns, and the overall length of the antenna. These parameters determine the antenna’s operating frequency, gain, and radiation pattern. The helical antenna is widely used in applications such as satellite communication, space probe communication, and radio astronomy due to its ability to produce a directional radiation pattern and to operate over a wide frequency band. How to Calculate Helical Antenna? This shows the angle at which the helical conductor is wound. When using a circumference C λ of 1, it essentially expresses the same thing as the turn spacing S λ. Similarly to the height A, this does not consider the pitch angle change in any impedance matching sections of the helix. Length of 1 turn (L t) The mathematical representation of a helix curve cannot be attributed to a single individual. It is a cumulative effort by many mathematicians and scientists across centuries. However, the concept of parametric equations, which is central to defining a helix curve, was introduced by mathematicians such as Carl Friedrich Gauss and Pierre-Simon Laplace in the 18th and 19th centuries. Real Life Application where HXL is the helix length, R is the rise of the helix in one revolution, and C is the circumference of the helix.The Length of a Helix calculator computes the linear length of a spiral or helix where the helix is pulled into a straight line. A HELIX is a three dimensional spiraling circular object. The most common application of the helix shape is in the common spring. A helix has a height or length, diameter and pitch, where pitch is the measurement between the spirals (see diagram). Helix Calculators:

Similar to the half power beam width, except the first null angle is estimated between the points of the lowest gain around the main lobe (nulls). Gain (G) Predicted total height of the helix. This does not include things like the reflector plate or the connector that increase the total height, or impedance matching which can decrease the height. Pitch angle (α) The field of geometry, particularly the study of curves and surfaces, has been shaped by many notable individuals. The Greek mathematician Euclid, known as the father of geometry, laid much of the groundwork. Later, the contributions of mathematicians like Carl Friedrich Gauss in differential geometry and Pierre-Simon Laplace in mathematical physics have significantly influenced our understanding of geometric structures like the helix curve. Interesting Facts The diameter of the helical antenna, measured between the center points of the conductor. Turn spacing - real (S) TL;DR: Keep your expectations realistic, if the theoretical performance shown by this calculator seems too good to be true, then it probably is. After building your helix, do a few tests to observe its performance and adjust it if necessary. For general purpose receive-only (or very low power transmit) applications based on already tested specifications, the estimations will be good enough. Height of the helix (A)

How does a helix work?

To calculate the helix length, the calculator uses the Pythagorean theorem to find the hypotenuse of a right triangle, where the rise of the helix is the height of the triangle and the circumference of the helix is the base of the triangle. The hypotenuse of the triangle is the helix length. Same as operating frequency F, except converted to wavelenght. Intermediary value used in other equations mainly for simplicity. For the purposes of this calculator, the wavelength is expressed in millimeters. Helix circumference - real (C) A helix, sometimes also called a coil, is a curve for which the tangent makes a constant angle with a fixed line. The shortest