This is also not ideal. The result is less signal strength. We are no longer picking up as much of a half cycle of a wave as possible, hence loss of overall signal. The final experiment we can try is to greatly increase the length of the arms of the dipole. If we make them long enough, there is no longer complete cancellation at the signal point at the junction of the arms. However, there are still bits of opposite-going signals induced on the individual arms, which will still cancel out on the arms themselves.
Any smaller and we will not be maximizing our signal pickup. Any longer and we will began seeing interesting cancellation effects in the dipole. A monopole antenna consists of one arm of a dipole placed over a ground plane, which serves as the other arm. You must be logged in to post a comment. Skip to content Search for: Search. The Simple Dipole Example The dipole is a basic antenna with two arms.
So what happens if we lengthen the dipole arms so that they are half a wavelength each? So what happens if we go shorter than half a wavelength? The Monopole Example A monopole antenna consists of one arm of a dipole placed over a ground plane, which serves as the other arm. Click here to register now.
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You should upgrade or use an alternative browser. Thread starter hiyan Start date Jan 16, Status Not open for further replies. Re: why have you read the book regarding these topics or mearly asking after attending any lecture? Re: why hiyan said:. Click to expand Re: why :?
Re: why hey , the high impedence is for matching purpose.. Add a comment. Active Oldest Votes. Improve this answer. John Rennie John Rennie k gold badges silver badges bronze badges. The match can be changed to work in at non-resonant frequency of the antenna and the efficiency of the antenna will be identical. For example notice how the impedance of an antenna repeats at multiples e. The two major disadvantages are: Due to the length the impedance will most likely cause a mismatch in the receiver causing loss of efficiency Longer length also will tend to pick up more background noise.
The impedance is only an issue between the antenna and the receiver. This is where the efficiency loss occurs, not in the interface of the EM wave to the Antenna. Also as they get longer they lose some signal power due to resistance. Sign up or log in Sign up using Google.
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