A 'polar' antenna radiation diagram. The radial distance from the center represents signal strength.Electronic scanning of a main lobe of a phased array. There are higher-order main lobes when scan is performed wide range.
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Bell Laboratories Layered Space-Time (BLAST)
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In a radio antennas, the main lobe or main beam is the region of the radiation pattern containing the highest power or exhibiting the greatest field strength.
The radiation pattern of most antennas shows a pattern of "lobes" at various directions, where the radiated signal strength reaches a local maximum, separated by "nulls", at which the radiation falls to zero. In a directional antenna in which the objective is to emit the radio waves in one direction, the lobe in that direction is designed to have higher field strength than the others, so on a graph of the radiation pattern it appears biggest; this is the main lobe. The other lobes are called "sidelobes", and usually represent unwanted radiation in undesired directions. The sidelobe in the opposite direction from the main lobe is called the "backlobe".
The radiation pattern referred to above is usually the horizontal radiation pattern, which is plotted as a function of azimuth about the antenna, although the vertical radiation pattern may also have a main lobe. The beamwidth of the antenna is the width of the main lobe, usually specified by the half power beam width (HPBW), the angle encompassed between the points on the side of the lobe where the power has fallen to half (-3 dB) of its maximum value.
The concepts of main lobe and sidelobes also apply to acoustics and optics, and are used to describe the radiation pattern of optical systems like telescopes, and acoustic transducers like microphones and loudspeakers.
In a radio antennas, the mainlobe or main beam is the region of the radiation pattern containing the highest power or exhibiting the greatest field strength...
sidelobes are the lobes (local maxima) of the far field radiation pattern of an antenna or other radiation source, that are not the mainlobe. The radiation...
Look up lobe in Wiktionary, the free dictionary. Lobe may refer to: Lobe (surname) Lobe (anatomy) Lobe, a large-scale structure of a radio galaxy Glacial...
causing grating lobes. Grating lobes are undesirable and identical to the mainlobe. The perceived difference seen in the grating lobes is because of the...
the mainlobe are called "side lobes". The minor lobe in the opposite direction (180°) from the mainlobe is called the "back lobe". Minor lobes usually...
determines the tradeoff between mainlobe width and side lobe levels of the spectral leakage pattern. The mainlobe width, in between the nulls, is given...
divided grossly into four parts or lobes: the right lobe, the left lobe, the caudate lobe, and the quadrate lobe. Seen from the front – the diaphragmatic...
distant receiver located in the direction of the antenna's strongest beam (mainlobe). ERP measures the combination of the power emitted by the transmitter...
parietal lobe is one of the four major lobes of the cerebral cortex in the brain of mammals. The parietal lobe is positioned above the temporal lobe and behind...
lobe the sound level, at the crossover frequency is much higher as compared to outside the lobe. Therefore loudspeaker designers try to make the main...
approximates the DPSS window which maximizes the energy concentration in the mainlobe but which is difficult to compute. The Kaiser window and its Fourier transform...
desired sensitivity patterns. A mainlobe is produced together with nulls and sidelobes. As well as controlling the mainlobe width (beamwidth) and the sidelobe...
antennas, virtually all the power radiated is concentrated in a narrow mainlobe along the antenna's axis. The residual power is radiated in sidelobes...
Lobe switching is a method used on early radar sets to improve tracking accuracy. It uses two slightly separated antenna elements to send the beam slightly...
Beam steering is a technique for changing the direction of the mainlobe of a radiation pattern. In radio and radar systems, beam steering may be accomplished...
frontal lobe is located at the front of each cerebral hemisphere and positioned in front of the parietal lobe and above and in front of the temporal lobe. It...
of the anterior pituitary lobe, the posterior pituitary lobe, and an intermediate lobe that joins them. The intermediate lobe is avascular and almost absent...
nulls, mainlobe, and grating lobes of the array. Referring to the exponents in the array factor equation, we can say that major and grating lobes will...
pattern of such an antenna consists of a strong beam in one direction, the mainlobe, plus a series of weaker beams at different angles called sidelobes, usually...
wavelength long, including the common quarter wave whip, have a single mainlobe, and with a perfectly conducting ground plane under it maximum field strength...
to ground. The antenna has a unidirectional radiation pattern with the mainlobe of the pattern at a shallow angle into the sky off the resistor-terminated...
the sidebands is significantly reduced compared to the mainlobe and the amplitude of the mainlobe is increased. Similarly, the use of a cosine pulse profile...
antenna would need to radiate to match the intensity of the transmitter's mainlobe. The terms power and energy are closely related but distinct physical...
symmetry of the parabolic dish, and the antenna radiation pattern (the mainlobe) is symmetrical about the boresight axis. Most antennas boresight axis...
direction of maximum gain (the mainlobe) is no longer perpendicular to the rods. Still, the radiation pattern will have lobes at an angle to the rods, making...
lobe disorder, also frontal lobe syndrome, is an impairment of the frontal lobe of the brain due to disease or frontal lobe injury. The frontal lobe plays...
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