CHAPTER 6
SINGLE – SIDEBAND COMMUNICATIONS
SYSTEMS
SINGLE – SIDEBAND COMMUNICATIONS
SYSTEMS
1) A form of amplitude modulation in which the carrier is transmitted at full power but only one of the sidebands is transmitted. AM Single-sideband Full Carrier ( SSBFC )
2) A form of amplitude modulation in which the carrier is totally suppressed and one of the sidebands removed. AM Single-sideband Suppressed Carrier ( SSBSC )
3) A form of amplitude modulation in which one sideband is totally removed and the carrier voltage is reduced to approximately 10% of its unmodulated amplitude. Sometimes called single-sideband reinserted carrier. AM Single-sideband Reduced Carrier ( SSBRC )
4) It is the reinserted carrier in SSBRC for demodulation purposes. Pilot Carrier
5) A form of amplitude modulation in which a single carrier frequency is independently modulated by two different modulating signals. AM Independent Sideband ( ISB )
6) A form of amplitude modulation in which the carrier and one complete sideband are transmitted, but only part of the second sideband is transmitted. AM Vestigial Sideband ( VSB )
7) ________ is the picture portion of a commercial television broadcasting signal. VSB System
8) Are obvious advantages of single-sideband suppressed- and reduced- carrier transmission over conventional double- sideband full-carrier transmission. Bandwidth Conservation and Power Efficiency
18) The small carrier component that is always present in the output signal of a balanced modulator. Carrier Leak
19) The operation of this balanced modulator as the balanced ring modulator, is completely dependent on the switching action of diodes D1 through D4 under the influence of the carrier and modulating signal voltages. Balanced Bridge Modulator
20) A double-balanced modulator/demodulator that produces an output signal that is proportional to the product of its input signals. LM1497 / 1596 Balanced Modulator IC
21) The circuit where the carrier is reinserted. Linear Summer
22) Three methods for single-sideband generation. Filter, Phase-Shift, and Third Method
23) Types of single-sideband filters. Crystal Lattice, Ceramic, Mechanical, Saw Filters
24) A mechanically resonant transducer that receives electrical energy, converts it to mechanical vibrations, and then converts the vibrations back to electrical energy at its output. Mechanical Filter
25) Filters that use acoustic energy rather than electro-mechanical energy to provide excellent performance for precise bandpass filtering. Surface Acoustic Wave Filters
26) Reflected energy that cancels and attenuates the incident wave energy. Destructive Interference
27) Reflected energy that aids the incident wave energy. Constructive Interference
28) A transducer which launches the acoustic wave in only one direction. Unidirectional Transducer
29) Any difference between the transmit and receive local oscillator frequencies produces a _______ in the demodulated information signal. frequency offset error
30) Fifty hertz or more offset is distinguishable by a normal listener as a _______. tonal variation
31) A narrowband PLL that tracks the pilot carrier in the composite SSBRC receiver signal and uses the recovered carrier to generate coherent local oscillator frequencies in the synthesizer. Carrier Recovery Circuit
32) An SSB receiver that uses a PLL carrier recovery circuit and a frequency synthesizer to produce coherent local and beat frequency oscillator frequencies. Multichannel Pilto Carrier
33) Systems that provide narrowband voice communications for land-mobile services with nearly the quality achieved with FM systems and do it using less than one-third the bandwidth. Amplitude Compandoring Single-Sideband ( ACSSB )
34) The process of combining transmissions from more than one source and transmitting them over a common facility, such as metallic or optical fiber cable or a radio-frequency channel. Multiplexing
35) A transmission that can be used to combine hundreds or even thousands of narrowband channels into single, composite wideband channel without the channels interfering with each other. Single-Sideband Suppressed-Carrier Transmission
36) Single-sideband transmitters are rated in ________ and ________. Peak Envelope Power ( PEP ) & Peak Envelope Voltage ( PEV )
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