Calculators

A series of Calculators for radio frequency engineers. These calculators help with unit conversions, VSWR calculations, attenuator design, antenna design, radars, and various other basic calculations that are often required.

SatNow Calculators

Anomalistic Period Calculator

The Anomalistic Period calculator calculates the time required by a satellite to complete one orbital period when measured from perigee to perigee (closest approach) or from apogee to apogee (farthest point). The Anomalistic Period is also referred to as the time elapsed between the successive perigee passages.
Antenna Efficiency Calculator

Antenna efficiency, also referred to as radiation efficiency, gauges how well an antenna can transmit its output power with the least amount of losses. Antenna efficiency calculator refers to the ratio of power radiated by the antenna to the power supplied to the antenna. Radiated power is the sum of all power radiated by an antenna connected to a transmitter.
Antenna G/T Ratio Calculator

Antenna Gain to Noise Temperature Ratio (G/T) is referred to as figure of merit of the antenna system. The ability of an antenna to emit more or less in any direction as compared to a theoretical antenna is known as antenna gain. All noise that enters a receiver through its antenna is measured as the antenna noise temperature.
Antenna Polarization Loss Factor (PLF) Calculator

The Antenna Polarization Loss Factor (PLF) is given as the efficiency of an antenna in capturing the incident power, accounting for polarization mismatches between the transmitting and receiving antennas. The Antenna Polarization Loss Factor (PLF) is important as it enables engineers to measure potential signal loss caused by polarization mismatches between transmitting and receiving antennas. This helps optimize antenna alignment and system design, reducing signal degradation and ensuring efficient communication in wireless systems.
Apogee and Perigee Distance Calculator

The Apogee and Perigee Distance Calculator is used to calculate the farthest and the closest distance of an object (satellite or moon) from the Earth. According to Kepler’s First Law, the orbit of a satellite revolving around the Earth is elliptical with the center of the Earth lying at one of the foci of the ellipse. This elliptical orbit is defined by its semi-major axis ‘a’ and eccentricity ‘e’.
Azimuth Angle Calculator

The azimuth angle of an Earth station is defined as the angle formed between the line of intersection of the plane passing through the satellite, the Earth station, and the center of the Earth with the true north and the local horizontal plane. This line of intersection between the two planes can be visualized as one of the many tangent lines at the Earth’s station location.
Bi-Elliptic Transfer Calculator

The Bi-elliptic Transfer is an orbital maneuver used to transition a spacecraft from one orbit to another. It involves transitioning through two elliptical orbits, making it a three-step process. Although it requires more time than a Hohmann transfer, it can sometimes save fuel for transfers between orbits with a large difference in radii.
Circular Orbit Satellite Velocity Calculator

The Circular Orbit Satellite Velocity Calculator is used to calculate the speed at which the satellite travels along the circular orbital path around the Earth. For calculating the velocity we assume a circular orbit with radius ‘r’. A circular orbit is a special case of an elliptical orbit where the semi-minor axis and the semi-major axis are equal to the radius.
Circular Orbit Time Period Calculator

The circular orbital period also know as the revolution period is the time taken by an object to complete one orbit around a celestial body. The orbit is a regular, repeating path and refers to the time it takes for a celestial body to orbit around its star, such as the Moon's orbit around the Earth or the time it takes for the Earth to orbit the Sun.
Coverage Angle of a satellite

The coverage angle (a) of a satellite is an angle that defines the area on the Earth's surface that the satellite can "see" or cover at any given time. It helps in planning satellite constellations, optimizing communication, and ensuring efficient coverage for services like broadcasting, navigation, and the Internet. Coverage Area is the area on Earth where a satellite can be seen at a minimum elevation angle. This coverage area is circular and determined by the satellite's orbital parameters such as Semi-Major Axis (a), Eccentricity (e), Inclination (I), etc. Satellite coverage can be influenced by factors such as atmospheric attenuation, obstacles blocking transmission, and electrical background noise from Earth.
Distance between Earth's Geocenter and Satellite Calculator

Geocenter refers to the Earth’s center and is the point around which the mass of the Earth is evenly distributed. The distance between the geocenter and the satellite is calculated by adding the distances between the ground station and the satellite and the earth’s radius. The theoretically calculated value of the Earth’s radius is the distance between the geocenter and the ground station which is approximated to be 6,378 km (3,963 mi).
Earth Station Altitude Calculator

A group of devices placed on the surface of the earth that allow communication over one or more satellites is known as an earth station altitude. For the purpose of estimating the effectiveness of satellite communication, the height of the rain is a crucial input element. The Slant Length is the length from the base to the peak of a lateral face. The angle of elevation is the angle formed between the object and the horizontal line of sight.
Earth Station Elevation Angle Calculator

The Earth Station Elevation Angle Calculator is used to calculate the angle between the line of intersection of the plane passing through the Earth station, the satellite, and the center of the Earth and the local horizontal plane with the line joining the Earth station and the satellite.
Effective Antenna Aperture Calculator

The effective antenna aperture/area is a theoretical value which is a measure of how effective an antenna is at receiving power. The effective aperture/area can be calculated by knowing the gain of the receiving antenna. Here we will calculate the effective antenna aperture of an antenna.
Effective Path Length for Estimating Rain Attenuation

The size of the rain cell, the rate of the rain, and the height of the rain, which are all influenced by the types of rain, define the effective path length for the estimation of rain attenuation over the Earth-space path.
EIRP Calculator

Effective Isotropic Radiated Power or Equivalent Isotropically Radiated Power (EIRP) is a measure of the radiated output power from an ideal isotropic antenna in a single direction. It is the maximum available radiation at the antenna after all power losses and gains in the system have been taken into consideration. This calculator calculates the Effective Isotropic Radiated Power.
Elliptical Orbit Satellite Velocity Calculator

The Elliptical Orbit Satellite Velocity Calculator is used to calculate the speed at which the satellite travels along the elliptical orbit path around the Earth. According to Keper’s first law, the orbit of a satellite around Earth is elliptical with the center of the Earth lying at one of the foci of the ellipse. Here for the velocity calculation, we assume an elliptical orbit with semi-major axis ‘a’.
Elliptical Orbit Time Period Calculator

The elliptical orbital period also known as the revolution period is the time taken by an object to complete one orbit around a celestial body. The orbit is a regular, repeating path and the orbital period in astronomy applies to satellites revolving around the earth, the moon orbiting the planets, asteroids, and planets orbiting the Sun.
Exhaust Velocity Calculator

Exhaust Velocity of a Rocket is the speed, in relation to the rocket, at which exhaust gases emerge from the nozzle of the rocket's engine. Specific impulse measures how effectively the energy content of the propellants is transformed into thrust, is the overall change in impulse per unit of fuel consumed.
Free Space Path Loss Calculator

The signal strength that is lost as a signal moves through empty space is known as the free space path loss. Typically, its value is determined by discounting any potential impediments or reflections in its path. The loss between two isotropic radiators in free space, as stated as a power ratio, according to IEEE standards. To determine the Free Space Path Loss, enter the Frequency, Distance, and System Gains. It's measured in dB.
Hohmann Transfer Calculator

The Hohmann Transfer orbit is a cost-effective technique for transferring a spacecraft between two circular orbits. The Hohmann transfer orbit involves two propulsion maneuvers: the first propels the spacecraft into an elliptical transfer orbit, and the second adjust it to achieve a circular orbit at the desired altitude. The Hohmann transfer is commonly used for orbital maneuvers, especially when transferring between low Earth orbit (LEO) and geostationary orbit (GEO) or other orbits at varying altitudes.
LEO Satellite Acceleration Calculator

The acceleration of the Low Earth Orbit (LEO) satellite can be calculated using the centripetal acceleration formula, which is the acceleration required to keep an object in circular motion, considering the orbit to be circular. Here we will calculate the acceleration of the satellite specifically for those satellites placed in LEO orbit. The radius of LEO is ranged within 2000 km as it is the maximum height of satellite that can be placed in the orbit.
LEO Satellite Angular Velocity Calculator

Angular Velocity of LEO satellite is the rate at which it moves around the Earth in radians per second. Here we will calculate the Angular velocity of the satellite specifically for those satellites placed in LEO orbit. The radius of LEO is ranged within 2000 km as it is the maximum height of satellite that can be placed in the orbit.
Light Speed Distance Calculator

We use light-time to measure the vast distances of space. It's the distance that light travels in a specific period of time. Also: LIGHT IS FAST, nothing travels faster than light.
Lumens Distance Calculator

A lumen (lm) is the unit of the International Measurement System that measures the luminous flux emitted by a light source. Luminous flux is the measure of brightness of a light source in terms of energy being emitted.
MEO Satellite Acceleration Calculator

The acceleration of the MEO satellite can be calculated using the centripetal acceleration formula, which is the acceleration required to keep an object in circular motion, considering the orbit to be circular. Medium Earth Orbit (MEO) satellite refers to the satellite placed in between 2000 Km and 35786 km height, which is above the LEO orbit and below the GEO orbit. Here we will calculate the acceleration of the satellite specifically for those satellites placed in MEO orbit.
MEO Satellite Angular Velocity Calculator

Angular Velocity of MEO satellite is the rate at which it moves around the Earth in radians per second. Medium Earth Orbit (MEO) satellite refers to the satellite placed in between 2000 Km and 35786 km height, which is above the LEO orbit and below the GEO orbit. Here we will calculate the Angular velocity of the satellite specifically for those satellites placed in MEO orbit.
Minimum Energy Required to launch a satellite

Minimum Energy Required to launch a satellite of mass m from the surface of the earth is the sum of gravitational potential energy and kinetic energy needed for the satellite to achieve the desired orbit.
Orbital Acceleration Calculator

Orbital acceleration is the acceleration directed at the center of the orbital path taken by a body in a circular motion. Orbital acceleration is also known as centripetal acceleration. The centripetal acceleration has a magnitude equal to the square of the body's speed v along the curve divided by the distance r from the center of the circle to the moving body.
Orbital Distance Calculator

Orbital Distance is used to determinate how long it takes for an object to revolve around another one. Here the objective is to calculate the orbital distance, squared the orbital period, then raise the result to the one-third power.
Orbital Speed Calculator

Orbital Speed is the speed at which an object travels in its orbit around another object relative to the center of mass of the larger object. In the case of Earth, Orbital Speed is the speed at which the Earth travels around the Sun in its orbit. This Calculator calculates the Orbital Speed of a celestial body around the Earth given its Radius of Orbit.
Parabolic Antenna Half Power Beamwidth Calculator

Half power beam width of a parabolic antenna is the angle in which relative power is more than 50% of the peak power, in the effective radiated field of the antenna. Here we will calculate the HPBW of a parabolic antenna.
Planet Mass Calculator

The masses of the planets are calculated most accurately from Newton's law of gravity-Every mass attracts every other mass.
Propellant Mass Fraction Calculator

A propellant (or propellent) is a mass that is expelled or expanded in such a way as to create a thrust or other motive force in accordance with Newton's third law of motion. The propellant mass fraction is the ratio between the propellant mass and the initial mass of the vehicle.
Rocket Acceleration Calculator

The acceleration of the rocket can be determined by Newton's Second Law of Motion. For a constant mass, this law can be written as force (F) equals mass (m) times acceleration (a); (F = m * A). We can solve for the acceleration using algebra ( A = F / m).
Rocket Equation Calculation

The rocket equation defines the relationship between the velocity of an object and exhaust speed and mass. In other words, it’s a way of describing the conservation of mass when applied to the mass.
Satellite Coverage Area

Satellite Coverage Area (%) of a satellite is the geographical region or area over which a satellite provides communication, broadcasting, or other services. In general, satellites are designed to cover specific regions or continents, although some satellites may offer global coverage. Here we will calculate the coverage area of the satellite for specific regions given the distance and radius.
Satellite Line-of-Sight Distance Calculator

The Satellites Line-of-Sight Distance Calculator calculates the distance between two satellites in an orbital path. This distance is computed from the triangle formed by the center of the earth and the points of location of the two satellites.
Satellite Slant Range Calculator

The Satellite Slant Range Calculator is used to calculate the range or distance of the satellite from the Earth station. The slant range of a satellite is directly proportional to the elevation angle. The larger the elevation angle of an Earth station, the smaller the slant range.
Slant Length Calculator

Slant Length is the distance measured along a lateral face from the base to the apex. This calculator helps to find the slant length using effective path length and reduction factor.
Specific Impulse Calculator

The Specific Impulse Calculator is used to calculate how efficiently a rocket engine or a thruster uses propellant to generate thrust. A propulsion system with a higher specific impulse value indicates that the propellant mass is utilized more efficiently.
Specific Orbital Energy for Elliptical Orbit

Specific orbital energy is a measure of the total energy (kinetic plus potential) per unit mass of an object in orbit. It describes the energy a satellite or any object in orbit has due to its position and velocity relative to the central body it is orbiting (such as a planet or star). The specific orbital energy of an elliptical orbit is determined by the semi-major axis and the gravitational constant of the central body.
Star Distance Calculator

The parallax angle is the angle between the Earth at one time of year, and the Earth six months later, as measured from a nearby star. Astronomers use this angle to find the distance from the Earth to that star. A second of arc, arcsecond (arcsec), or arc second, denoted by the symbol ?, is 1/60 of an arcminute and 1/3600 of a degree.
Symbol Rate Calculator

The number of symbols that are changed in a signal every second is known as the Symbol Rate or Baud Rate. Each symbol can represent one, two, three, four, or more bits of transmission rate data depending on the modulation coding method (MODCOD) being utilized. The rate at which symbols are transmitted is the baud rate.
Thrust Calculator

Thrust is defined as the total force generated by the exhaust of burning fuel in a rocket. It is a reaction force described quantitatively by Newton's third law. When a system expels or accelerates mass in one direction, the accelerated mass will cause a force of equal magnitude but opposite direction to be applied to that system.
Vis-Viva Equation

The Vis-Viva Equation is a formula used to calculate the speed of an object in orbit based on its distance from the center of the body it is orbiting and the mass of that body. It is the fundamental formula in orbital mechanics that describes the relationship between a satellite's speed, its distance from the central body, and the orbit's size. It applies to objects in circular, elliptical, parabolic, and hyperbolic orbits around a massive central body, such as Earth or the Sun. Orbital Mechanics is the branch of physics and engineering that deals with the study of the movement of objects in space, influenced primarily by gravity. It is a specialized area within celestial mechanics that focuses on understanding the paths, or orbits, that objects like satellites, spacecraft, and natural bodies follow as they are governed by gravitational forces, especially from celestial bodies such as planets, moons, and stars.