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Without modulation, there's be no way to get any information onto a carrier signal.
There are several different types of modulation schemes for radio carriers and almost as many different types demodulators to decode the information so that it can be converted into a usable form. For instance, AM (amplitude modulation), FM (frequency modulation), digital modulation, quadrature amplitude, etc.
What else can I help you with?
What is meant by non constant envelope modulation?
A constant-envelope modualtion is a modualtion scheme in which the amplitude of the modualted tone remains constant with time. Main advantage of such modualtion schmes is that they relax the linearity requirements of the power amplifier (PA) and hence a less linear and more efficient PA can be used. Most modualtion schemes are not constant-envelope. For example, BPSK, QPSK, 16-QAM are not constant-envelope. Few modualtion schemes such as GFSK are constant-envelope.
What factor determines the spacing of the sidebands in an amplitude modulated signal?
Its a function of the signal bandwidth. If you modulate a 1 MHz carrier with a 1 KHz sine wave, you will see three peaks in the frequency domain - the carrier - the carrier minus 1 KHz - and the carrier plus 1 KHz. If the carrier is 100 MHz, the spacing is still the same, unless you consider spacing to be proportional to the carrier frequency - but that does not seem to be the question. Improved. Bandwidth is a function of modulating frequency in simple Amplitude Modulation. As described above, 1 MHz signal with 1 kHz modulation creates a lower side frequency (1000 - 1) = 999 kHz, the carrier = 1000 kHz and the upper side frequency 1001 kHz. These two side frequencies exist up to the point of 100% modulation. Over 100% modualtion, large numbers of extra side frequencies ("Splatter") will exist. Since we rarely use single-tone modualtion, but a spectrum of modulating frequencies, the upper and lower energy appears within the two side bands - commonly called sidebands. The composite signal now comprises a lower sideband, which (for a maximum modulating frequency Fm) extends "down" to Fc-Fm, the carrier (Fc), and the upper sideband, which extends "up" to Fc+Fm. Be aware that advanced AM techniques, such as SSB-SC and VSB may use half the bandwidth of full-carrier, both-sidebands AM. Also, be aware that AM techniques used in digital data (QAM, Trellis coding, etc) processing differ from the "audio/broadcast" descriptions above.
Is the YOU NEED a verb?
You need. You is a pronoun; need is a verb.
Does pentagon have perpendicular lines?
It can, but need not.It can, but need not.It can, but need not.It can, but need not.
What is the future tense of need?
Needed is the past tense of need. The future tense of need is will need.
What is project delphis?
i need a answer i need a answer i need a answer
Do you need to be a doctor to be a hospital administrator?
No you do not. You need to be an excellent administrator.No you do not. You need to be an excellent administrator.No you do not. You need to be an excellent administrator.No you do not. You need to be an excellent administrator.No you do not. You need to be an excellent administrator.No you do not. You need to be an excellent administrator.
How many planes of symmetry does a icosahedron have?
It need not have any.It need not have any.It need not have any.It need not have any.
No, You need to add cables in the lengths you need.?
No, You need to add cables in the lengths you need.
What do you need to be a pedtricain?
what do i need and what do i need to know to be a pedtricain
Need to clarify or need your clarification?
need your clarification
What i need to do?
what i need to do
