{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

WilliamsA2

# WilliamsA2 - Shadia Williams Patrick Behr Naman Batt 1 All...

This preview shows pages 1–5. Sign up to view the full content.

Shadia Williams Patrick Behr Naman Batt 1. All the frequency: 1502 kHz, 1500 kHz, 1498 kHz 2. 2 kHz 3. The increase and decrease in the AM waveform’s amplitude causes the side band frequency. 4. The upper side band and lower side band determine bandwidth. 5. A sideband carries the modulation or "information". In old fashioned AM and FM transmission schemes, a carrier is broadcast in addition to the sideband(s). Only the sideband is needed to communicate. A spurious frequency that happens when a carrier is transmitted has no added "information" and just adds to the transmission bandwidth. Sometimes these occur by intermixing within the transmitter. A common example is CB splatter from overdrive of RF amps. 6. At point 6 the side bands combine to equal the opposite of the carrier, resulting in the zero amplitude AM signal. 7. The length of the phasor will be equal to the amplitude of the signal (or if the amplitude is very big it has to be analogous to it) and if the phasor has a phase shift relative to other phasors with the same frequency you have to draw it with the appropriate angle on the diagram. 8. Phasor Representation

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Shadia Williams Patrick Behr Naman Batt 9. Percentage modulation 10. Overmodulation results in spurious emissions by the modulated carrier, and distortion of the recovered modulating signal. 11. %m= (400-300/ 400+300)*100% = 14% %m= (500-300/500+300)*100% = 25% %m= (600-300/600+300)*100% = 33% 12. % m = B-A/B+A x 100% % m = (200-60/200+60) x 100% % m = 140/260 x 100% % m = .53846 x 100%
Shadia Williams Patrick Behr Naman Batt % m = 53.846 = 53.85% 13. 53.85 = Em/65 x 100% 53.85 = Em/65 Em = 53.85 x 65 Em = 35 Vpk 53.85 = 35/Ec x 100% 53.85 x Ec/35 = 100% Ec/35 = 1/53.85 Ec = .0185701021 x 35 Ec = .649953 = 65 Vpk 14. ESF = m Ec/2 - The carrier amplitude and frequency always remain constant, while the sidebands are usually changing in amplitude and frequency. 15. ESF = m Ec/2 ESF = .75 x 100/2 = 37.5 V 16. Pt = Pc (1 + m ²/2) Pt = 16 (1 + .7²/2)

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Shadia Williams Patrick Behr Naman Batt Pt = 19.92 19.92 = Pc (1 + .7²/2) Pc = 19.92 / (1 + (.7²/2)) = 16W (19.92 – 16) / 2 = 1.96 Pusb = Plsb = 1.96W 17. Pc = 500 / (1 + (.75²/2)) = 390 W Pi = Pt – Pc = 500 – 390 = 110 W 18. It = Ic v(1 + ( m ²/2)) 6.7 = 6.2 v(1 + ( m ²/2)) 1 + m ²/2 = (6.7/6.2)² m ² = 2((6.7/6.2)² - 1) = .34 m = v(.34) = .5793 % m = .5793 x 100% = 57.93% 19. It is important to use as high a percentage modulation as possible.
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 11

WilliamsA2 - Shadia Williams Patrick Behr Naman Batt 1 All...

This preview shows document pages 1 - 5. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online