A half-wave antenna designed for 915MHz is excited with I- 100mA. Calculate the power density at...
Calculate the maximum power density 1 km away from a half-wave dipole antenna that is radiating 100 milliwatts. Repeat the calculation for a dipole antenna that is much shorter than a wavelength. (The gain of a half-wave dipole antenna is 2.15 dBi.)
5.8 : Calculate the antenna calibration factor for a half-wave dipole designed to operate at 1 GHz. When this antenna is connected to a cable having 0.5 dB loss, the power available at the receiver input terminals is −10 dBm. Under these conditions, what is the measured electric field strength in dBV/m?
A half-wave dipole (antenna efficiency= 80%) is driven by an input current of 0.5A (RMS). Determine the maximum radiation power density and the corresponding electric field strength at a point 200 m away from antenna.
An array antenna consists of two identical half-wave dipole antenna elements. The array operates in air at 100 MHz. User A is in the azimuth plane of the array, on a line that makes 60° with the line defined by the antenna elements. The driving current has no phase shift. What is the shortest physical distance, d, between the antenna elements in the array that will ensure maximum signal strength in the direction of the user? I lew 600 d
A linearly polarized uniform plane wave traveling in the + z direction, with a power density of 10 milliwatts per square meter, is incident upon a CW circularly polarized antenna whose gain is 9 dB at 11 GHz. Find the (a) maximum effective area of the antenna (in square meters) (b) power (in watts) that will be delivered to a load attached directly to the terminals of the antenna. m2 Watts
A linear antenna array comprises 5 half-wave dipoles arranged parallel to each other, lying in a plane and spaced \/2 apart. If the dipoles are fed 'in phase" (a) Write the expression for the normalised field pattern of the array (b) Plot, with aid of a computer, the field pattern in (a) (c) Calculate the angular width of the main beam at the half-power points and between the first nulls. A linear antenna array comprises 5 half-wave dipoles arranged parallel...
Consider a horn antenna that a half-power beam widths in the principal planes of HPBpl19, HP29°. What is the approximate directivity in dB if the pattern is a single lobe? If the radiation efficiency of the antenna is ε-90% , what is the gain of the antenna in dB. E-plane H-plane
A radio antenna broadcasts a 1.0 MHz radio wave with 25 kW power. Assume the radiation is emitted uniformly in all directions. 1) what is the wave's intensity 30 km from the antenna 2) what is the electric field amplitude at this distance?
2. a. Discuss the practical importance of the antenna beam width b. For an Omni-directional antenna the measurements show the Half Power Beam Width (HPBW) in vertical and horizontal planes are 30° and 20° respectively, antenna has loss resistance of 25Ω and efficiency η-0.8,Find: i. Antenna's gain in dB, and ii. Radiation resistance. 2. a. Discuss the practical importance of the antenna beam width b. For an Omni-directional antenna the measurements show the Half Power Beam Width (HPBW) in vertical...
11.12 The amplitude of the electric field intensity of a half-wave dipole antenna at r 5 km and /6rad is 0.01 V/m in free space. If the operating frequency is 30 MHz, determine its length and the total power that it radiates. Alse, write express 11.12 The amplitude of the electric field intensity of a half-wave dipole antenna at r 5 km and /6rad is 0.01 V/m in free space. If the operating frequency is 30 MHz, determine its length...