Communications Engineering Coaching Materials: Section 5 Module 22

This is the Section 5 Module 22 of the compiled Communications Coaching Materials taken from various sources including but not limited to past Board Examination Questions in Electronic System and Technologies (EST), Communications Books, Journals and other Communications References. This particular Coaching Notes in Communications Engineering has random Questions and Answers in random topics. Make sure to familiarize each questions to increase the chance of passing the ECE Board Exam.

Communications Engineering Coaching: Section 5 Module 22

QUESTIONS	ANSWER
121. Corresponds to a resonant transmission line, and the dipole antennas describe so far have been resonant	Resonant antenna
122. Which of the following is referred to as true 3G	UMTS
123. Bis means	Encore
124. Which of the following causes great damage to the cornea of the eye	Longer wavelength
125. Which of the following causes great damage to the retina of the eye	shorter wavelength
126. Variation delay form in ATM	Cell jitter
127. Embedded overhead bit	Payload
128. Commonly used in electro-optic crystal for polarization modulation	Lithium Niobate
129. Combination of circular and elliptical orbit	ELLIPSO
130. _______ ratio measures accuracy of cell transmission	Cell error
131. A coupler consist of series of lenses and partly reflective surfaces	Beam Splitting Coupler
132. Major difference of SONET and SDH	Data rate
133. Coherence of laser light is important to _______.	Holography
134. An optical detector for high sensitivity and bandwidth	PMT
135. Same information with dynamic range	Optical input power
136. Spectral width of laser in fiber optic	2nm
137. Spectral width of LED in fiber optic	30nm
138. Typical spectral width of laser ranges from 1nm to ____	5nm
139. Different packet types in X.25 switching	6
140. A single mode fiber optic cable has a diameter of	0.01
141. A step index multimode fiber optic cable has a diameter of	0.02
142. Packet switching	Layer 3
143. Thickness of optical disk	5mils
144. Used in 3D,.form depth video signal	Anti-logarithmic amplifier
145. Which of the following is not a fiber optic loss	Reflection
146. Diameter of VSAT is between 0.3m to _______	0.9m
147. Morning primetime block for AM in Metro Manila	5am to 9am
148. Parameter determines the range or the spectral length	Spectral response
149. Refers to variety of value added features	Control Information
150. Refers to mobile station identifier sent over on the air interface	Temporary Mobile Station Identifier
151. White streak	Blip
152. 16 bit network number (IP Addressing)	Class B
153. Illuminates only small portion of the fiber core	Effective Modal Bandwidth
154. National Building Code	PD 1096
155. Completely fills the core and the cladding of the front end of the fiber.	Overfilled launched bandwidth
156. Helium laser was discovered by A. Javen in	1960
157. Ratio of the speed of air and the speed of another substance	Index of refraction
158. Number of electrons emitted per second times the electron charge	Photocurrent
159. Integration of video, data in high speed	Fast Packet Concept
160. Laser light is bright mainly because it is	coherent
161. Angle separation of 8PSK	45O
162. Wavelength dependence index of refraction	Modal Dispersion
163. An episode used to give sample of the style of a writer?	Pilot
164. The Bandwidth of a fiber is limited to	Dispersion
165. The loudness of a sound depends upon the energy of motion imparted to ____________ molecules of the medium transmitting the sound.	vibrating
166. What alloy is formed using Iron, aluminum and silicon used as videoheads in video recording tapes	Alfecon
167. A technique used in transmitting multiple copies of information over the network to avoid deep fade	Diversity
168. In KBP television broadcasting, the commercial payload for a station should not exceed ________ minutes in Metro Manila	18
169. In KBP television broadcasting, each station should allot ____ minutes of newscast (local or foreign) from Monday to Friday	30
170. In acoustics, it is a sequential musical note	Tempo
171. The harmonically related carrier (HRC) shifts all cable channels 2 to 125 down to frequency -1.25 MHz are done to what channel pairs?	3-4, 5-6, 4-6
172. The OSI layer responsible for network availability, data storage and process capacity	Session Layer
173. A type of error of which two or more data units have changed	Burst Error
174. Which of the following is/are true about Spectrum Management?	It performs forward error correction; It provides automatic congestion control in the upstream direction; It performs upstream frequency agility to avoid igress in noise
175. The time it takes for the intensity of sound energy in the room to drop to one millionth of its initial value	Reverberation time
176. The persistence of sound even after a sound reflection occurred	Reverberation
177. Which of the following is true about Consumer DSL	It has a data rate of 176 kbps in the upward direction; It has a data rate of 1Mbps in the downward direction; It has lower speech communication capability
178. In an empty GSM timeslot or certain timeslot, data service is sent to the direction of packet switch data over what GSM network	GPRS
179. There are _________ primary unshielded twisted pair cables as classified by EIA/TIA 568 standard	7
	Dead Zone
181. Is a modulation / multiplexing technique wherein the information and sidebands are distributed over very wide bandwidth	Spread Spectrum
182. Which of the following is true about UMTS?	The ITU-T named it IMT2000; Has packet data service; Has initial speed of 28.8 kbps
183. What modulation technique is used by GSM?	Frequency Hopping
184. A system which has access to all individual users of the entire network	Server
185. A system which contains shared files to all individual users	Servers
186. A single transmission path from transmitter to receiver in the direction of line of sight range	Hop
187. A fixed cell length is how many bytes	53 bytes
188. Which of the following materials is sensitive to light?	Photoresist
189. A loss incurred of an electromagnetic wave travelling in a straight direction in a vacuum without absorption or reflection of medium of nearby objects	Free Space Path loss
190. An executive order regulating the operation of cable antenna television systems in the Philippines, and for other purposes	EO 205
191. An executive order which grants the NTC jurisdiction, control and regulation over the Philippine Commercial Satellite Corporation.	EO 196
192. A type of fiber optic cable which is always tightly buffered.	Plastic Clad Silica
193. It states that light wave behaves as if it is consists of many tiny particles	Quantum Theory
194. The highest central office in the DDD network	Regional Center
195. When a photodiode is used as fiber optic detector, it must be	Reversed bias
196. A diode used as an optical transmitter in fiber optics communication system	APD
197. From mobile station to base station	Reverse Link
198. Refers to the number of electrons emitted per second, times the electron charge	Photocurrent
199. A portion of the geosynchronous orbit where optimum coverage of a country is known as __________ location	Arc of Good
200. A geosynchronous satellite must be positioned at _______	0 degrees latitude
201. How many polar satellites are needed to complete one revolution	1
202. A licensed ECE is needed if a station transmit power exceeds?	3kW
	Conduit
204. For a music lover concert “A” is 440 Hz, if a musical note one octave higher were played, it would be ____ that frequency	Double
205. In a 220 Hz tone, an octave lower will result to ________?	110Hz
206. The digital signal level __ uses binary line coding scheme	1
207. Voice channels are also known as	Traffic channel
208. Connects to other offices and does not go directly to subscribers	Tandem Office
209. In a telephone channel bandwidth of 300 to 3000 Hz, the highest theoretical bandwidth rate is	5400 bps
210. With 8-bit processing, how many elements are contained in the channel?	2048 ports
211. What happens to the frequency and wavelength of a material if it enters from one medium to another type of medium with a change in speed?	The frequency remains the same but the wavelength changes
212. The main benefit of light-wave communications over microwaves or any other communications media	Wider bandwidth
213. Microwave communications is used in frequencies above?	1GHz
214. Waveguide becomes compulsory above what frequencies?	3GHz
215. It refers to an electromagnetic wave of which it is contained in a conduit	Guided Transmission Medium
216. What is the average loss in fiber splice?	0.15 dB
217. Is the sound energy per unit area at right angles of the propagation direction per unit time	Sound Intensity
218. Octave A ratio of two frequencies at	2:1
219. Pin 21 in the RS 232 Interface D connection	Signal Quality detector
220. An additional noise attributed to wind and environmental noise	Ambience
221. Refers to the direction of the electric field vector in space	Polarization
222. Is an antenna array which is highly directional at right angles to the plane of the array	Broadside Array
223. The transmission of information from multiple sources occurring on the same facility but not at the same time	TDM
224. The most widely used fax standard	Group III
	63, 535 octets
226. The highest layer in the ISO protocol Hierarchy	Application Layer
227. Is a non-coherent light source fo optical communications system	LED
228. Which of the following is used as an optical receiver in fiber optics communications	APD
229. Is the result of photons of light that are absorbed by the atoms of the glass core molecules	Infrared Absorption
230. What parameter of light detector determines the range or system length that can be achieved for a given wavelength?	Spectral Response
231. Dark current in light detectors is caused by?	Thermally generated carriers in the diode
232. What is the typical wavelength of light emitted from epitaxially grown LEDs?	940 nm
233. Which is not a possible cause of fiber optic loss?	Stepped Index Operation
234. When light strikes a flat polished end of a fiber, it produces a loss of?	4%
235. An increase in light intensity produces fast optic switching due to?	Amplification of optical signal
236. Optical fibers for telecommunications are typically about ___ mils thick and consist of a glass core, a glass cladding of lower index of refraction, and a protective coating	5
237. Material dispersion is caused by the?	Wavelength dependence of the index of refraction
238. One of the following is not a solid state optical detector?	PMT
239. Which optical detector is used when high sensitivity and bandwidth are required?	PMT
240. A radio station has a _ years of legal operation and shall renew for the same duration of operation	15

Complete List of Communications Engineering Coaching Materials

Communications Engineering Coaching Materials

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