1. Radio interference can be broadly categorized into ( ) levels.
A. Level 3 B. Level 4 C. Level 5 D. Level 6
Answer: A (permissible interference, acceptable interference, harmful interference).
2. In a GSM base station test, the operating frequency of a transmitter was measured to be 950.200 MHz, and the transmitter was operating on the ( ) channel.
A. 86 B. 76 C. 66 D. 96
Answer:B.
3. In a GSM base station test, a transmitter is measured to be operating on channel 100, which is ( ).
A. 945.000MHz
B. 955.000MHz
C. 965.000MHz
D. 985.000MHz
Answer: B.
4. The operating frequency range of 80-meter-band radio direction-finding is ( ).
A. 144-146 MHz
B. 3.5-3.6 MHz
C. 88-108 MHz
D. 825-835 MHz
Answer: B.
5. The transmit power of the public walkie-talkie should be no more than ( ).
A. 1 W B. 3 W C. 0.5 W D. 0.25 W
Answer:C.
6. The public intercom channel interval is ( ).
A. 10.50 kHz B. 12.50 kHz C. 15.50 kHz D. 12.00 kHz
Answer.
7. The international letter OFTA stands for ( ).
A. oliver, foxtrot, tango, alfa
B. oscar, francis, tommy, alfa
C. oscar, francis, tommy, anna
D. oscar, foxtrot, tango, alfa
D. alfa
Answer: d .
8. When a very strong interference signal exists in the outside world, due to the nonlinearity of the receiver can still cause a reduction in the gain of the useful signal (suppressed) or the noise is increased, so that the sensitivity of the receiver is reduced, this kind of interference is called ( ) interference.
A. Same channel
B. Neighboring channels
C. Spurious radiation
D. Blocking
Answer: D
9, two or more radio stations using the same frequency and the resulting interference is ( ).
A. Neighboring Channel Interference
B. Same Frequency Interference
C. Blocking Interference
D. Spurious Interference
Answer: B.
10. Radio waves propagating on the surface of the earth are called ( ).
A. Sky waves B. Earth waves C. Space waves D. Scattered waves
Answer: B.
11. The required bandwidth that is just sufficient to ensure the required information transmission at the appropriate rate and under the specified conditions for a given class of emission is called ( ).
A. Occupied bandwidth B. Channel C. Bandwidth D. Necessary bandwidth
Answer: D.
12, in the 1860s, the British physicist ( ) in the summarization of the results of the previous study of electromagnetic phenomena on the basis of the establishment of a complete theory of the electromagnetic field.
A.Einstein B.Hertz C.Newton D.Maxwell
Answer:D.
13, the units of both gain and loss can be expressed in ( ).
A. Hz B. dB C. W D. G
Answer：B.
14、Electromagnetic compatibility analysis of the English acronym is ( ）
A. EMI B. RFI C. EMC D.ITU
Answer：C.
15、HF electromagnetic waves are mainly transmitted by the way of ( ） transmission.
A. sky wave B. troposphere C. ground wave D. line-of-sight
Answer:A.
16, VHF electromagnetic waves can be transmitted up to ( ) kilometers.
A. tens B. hundreds C. thousands D. tens of thousands
Answer:B.
17, "Chinese people*** and the State Radio Regulations" is ( ).
A. State laws
B. State administrative regulations
C. Government regulations
D. Normative documents
Answer：B.
18、The basic principle of radio management is ( ).
A. Unified leadership
B. Unified planning
C. Division of labor management
D. Hierarchical responsibility
Answer: A, B, C, D
19, in the international confirmation of the third-generation mobile communication standards, China has proposed with independent intellectual property rights of the technological system is ( ), and it is the key technology is synchronous technology, software radio technology and smart antenna technology, etc.
A: W-CDMA
B: cdma2000
C: TD-SCDMA
D: cdma 1x
Answer: C.
20. When the measured signal level is low, the calculation of the actual signal level must take into account the effect of the noise background of the spectrum analyzer on the accuracy of measurement. In order to reduce the impact of internal noise on the measurement results, usually in the actual test process, the internal noise of the spectrum analyzer should be kept lower than the measured signal ( ) dB or more,
A: 5
B: 10
C: 15
D: 20
Answer: D.
2. Fill in the blanks
1, Receiver gain loss is affected by factors such as , , and ancillary equipment (filters, combiners, isolators).
Answer: antenna gain, connector loss, cable loss
2, in the radio transmitting equipment testing of the four conventional indicators are , , and spurious emissions.
Answer: frequency tolerance, transmit power, occupied bandwidth.
3, 3G is the abbreviation of English, refers to the first generation of mobile communications technology.
Answer: 3rd Generation, three.
4, intermodulation interference, refers to when one or more frequency signals at the same time into the receiver (transmitter), due to the nonlinearity of the circuit and the production of a third frequency known as the intermodulation frequency f0, if the frequency f0 happens to fall into a radio station's operating frequency, the station will be interfered with, that is, intermodulation interference.
Answer: two, two.
5, same-frequency interference (same-channel interference) refers to where the carrier frequency and the carrier frequency of the signal is the same, and in the way of non-useful signals into the intermediate frequency passband of the receiver caused by the interference, are known as same-frequency interference.
Answer: useful, same.
6, spread spectrum communication is divided into: (DS), (FH), time-hopping spread spectrum (TH) and linear frequency modulation (chirp Modulation) four basic ways. Among them, the more commonly used are DS and FH.
Answer: direct sequence spread spectrum, frequency hopping spread spectrum.
7, radio equipment testing is the radio regulatory agencies at all levels in accordance with the national , and , the quality of radio equipment to implement a supervision and inspection activities.
Answer: relevant laws, regulations, specific provisions.
8, the propagation of radio waves are mainly , , , , .
Answer: ground waves, sky waves, space waves, scattered waves.
9, CDMA is an acronym for Code Division Multiple Access, which means , is a digital interface technology that has only recently been used commercially.
Answer: Code Division Multiple Access.
10. Global System for Mobile Communications is an abbreviation for .
Answer: Global System for Mobile Communications.
11、High-voltage power transmission lines can be a source of interference when they are close to monitoring buildings or antennas. Therefore, when the high voltage line exceeds 100kV, the distance from the monitoring station and antenna is not less than .
Answer: broadband noise, 1km.
12, high-frequency carrier amplitude is modulated, known as; when the frequency is modulated, known as; if the modulation is the initial phase, known as .
Answer: amplitude modulation, frequency modulation, phase modulation.
13, the ratio of the average power of the signal to the average power of the noise is called .
Answer: signal-to-noise ratio.
14, the radio spectrum resources belong to all .
Answer: the state.
15, in the land mobile communication system calculations are often used in the modified EGLI model, the use of EGLI to calculate the path loss (P), P = 40lgD-20lg (Ht + Hr) + 20lgF + 72.1146, the formula of the Ht, Hr refers to .
Answer: the effective heights of the transmitting and receiving antennas.
16, electronic compass induction indicates a point of , that is, the Earth's magnetic field of the north; but marked on the map for , the difference between the two is called the magnetic declination of the point.
Answer: magnetic north, true north.
17. Radio regulation is the management of the activities of development, use, research and resources through planning, control, coordination, supervision and other means and methods.
Answer: radio waves, satellite orbit.
18, radio management work in the management method, usually using , ,
and four management tools.
Answer: administrative, legal, technical and economic.
19, the basic functions of the radio regulatory body is the function of guidance, , ,
and supervision.
Answer: management function, service function, coordination function.
20, set up the use of radio stations should have the main conditions: (1) radio equipment in line with; (2) the working environment is safe and reliable; (3) the operator has the appropriate; (4) the appropriate management measures.
Answer: national technical standards, business skills and operating qualifications.
21, according to the use of frequency bands, radio stations have , , , ultra-short wave radio and microwave radio and other types.
Answer: long wave radio, medium wave radio, short wave radio.
22, according to the scope of business, radio stations have fixed business radio, land mobile business radio, aviation business radio, water business radio, , , and other types.
Answer: broadcasting operational radio, meteorological operational radio, amateur radio, space operational radio and other optional.
23. The state's policy on the management of amateur radio is to "actively foster , , , and strictly manage".
Answer: Correctly guide and promote the development.
24, the standard radio station refers to , , in the factory as an integral part of the means of delivery must be installed radio communications equipment.
Answer: ships, trains, aircraft.
25, emergency position radio beacon radio is used for mobile services, its transmission is used to
and work to provide convenience.
Answer: search and rescue, rescue .
26. It is the certificate of legal use of the radio station by the unit or individual who set up the station.
Answer: radio license.
27, refers to, in a specific time, area, frequency band range, all or part of the radio transmitting equipment and other radiation of radio waves of the use of equipment to take a mandatory administrative measures.
Answer: radio control.
28, "the Chinese people *** and state radio frequency division regulations" is an important part of the radio management regulations, is the radio frequency division, allocation, assignment and management of the basic, programmatic, guiding documents, is the radio transmitting equipment, sales and use of the basis.
Answer: development, production, import.
29, in the international radio frequency regional division, China belongs to ( ) area.
Answer: third.
30, "radio frequency division of the provisions of the body including the type of business and division, general provisions, the International Telecommunication Union radio frequency division of the footnotes, *** five items.
Answer: radio frequency division table, China's radio frequency division footnote.
31, radio frequency refers to the national frequency management regulations to authorize the use of a unit or individual radio station in the specified conditions of the radio frequency.
Answer: assignment.
32, set up a unit in violation of radio management regulations, apply for a long period of time without the use of frequency or frequency use, overdue, the radio administration has the right to its approved frequency recovery.
Answer: Renewal of formalities.
33, the use of frequency units should be: (1), must comply with the provisions of the national frequency management, strictly according to the approved frequency work, no unauthorized changes; (2), shall not be unrelated to the work of the signal. (3), pay the frequency occupation fee on time.
Answer: send receive.
34、Any unit or individual who needs to continue to use the frequency after the expiration of the frequency use period must go to the original radio administration organization for formalities.
Answer: Renewal of use.
35, spectrum management of electromagnetic compatibility analysis refers to, in order to ensure that the radio communication equipment or system, in the public **** electromagnetic environment to fulfill its own design function at the same time, on the same environment of other equipment neither produce nor suffer harmful interference and .
Answer: technical analysis calculations.
36, the radiation of radio waves of non-radio equipment are , , equipment, electrified transportation systems, high-voltage power lines and other electrical devices.
Answer: industrial, scientific, medical equipment,.
37, the implementation of radio management supervision and inspection of the form of , , and file inspection of four.
Answer: regular inspection, irregular inspection, special inspection.
38, violation of radio management regulations, according to the facts and circumstances of the violation, may be punished by , , ,; serious cases, may also be imposed more than 1,000 yuan, less than 5,000 yuan fine or revocation of its radio license.
Answer: warning, seizure or confiscation of equipment, confiscation of illegal income.
39, violation of radio regulations, constitute a violation of the regulations on public security management penalties, may be subject to , , until the penalty of re-education through labor.
Answer: administrative detention, fines.
40, the radio station license shall not be lent to others to use, is strictly prohibited or .
Answer: imitation, forgery.
41, violation of the radio call sign management and use of the provisions of: private preparation, use of radio call signs; confusion and abuse of radio call signs; fraudulent use of .
Answer: other radio call signs.
42, violation of the confidentiality of radio communications: the use of secret language, code of communication but the use of plain language, code, resulting in leakage of confidentiality; the use of plain code mixed; private compilation, the .
Answer: code, secret language.
43. The main tasks of the radio monitoring network are , and .
Answer: monitoring, listening, direction finding.
44, radio equipment testing is the radio regulatory agencies on the quality of all types of radio equipment to implement the activities.
Answer: Supervision and Inspection
45, GPRS General Packet Radio Service is a solution for high-speed data transmission in mobile environments, which can provide variable traffic from the...
Answer: 10kb/s to 150kb/s
46, radio test system error is mainly composed of , , and the spectrum analyzer itself.
Answer: antenna gain error, low noise amplifier error, feedline loss error.
47, according to the international telecommunication union "radio rules", telecommunication (telecommunication) is defined as the use of wired electricity, light or other For the symbols, signals, text, images, sound or any nature of information transmission, transmission or reception. Radio communication is telecommunication using radio waves.
Answer: radio, electromagnetic systems.
48, the Chinese people *** and state radio frequency division regulations, radio frequency division table *** divided into four columns, respectively , , and .
Answer: "China division", "Hong Kong division", "Macau division" "international division ".
49. Frequency allocation refers to the approval of frequencies to a region or department for use under specified conditions. For example, China allocates MHz frequencies to China Mobile Group Corporation and MHz frequencies to China Unicom Group Corporation for use in the 900MHz GSM frequency.
Answer: 885-909/930-954, 909-915/954-960.
50. Radio frequencies are generally designated or approved for use by a service or user in three ways: through , and .
Answer: frequency division, frequency allocation, frequency assignment.
Three, judgment questions
1, the English abbreviation for AM wave is AM, according to the use of different frequency ranges can be divided into long-wave, medium-wave, short-wave, the corresponding English abbreviation for the LW, MW, SW.(Right)
2, ultra-short wave wavelength between 10M-1M, can only be used in the land-wave propagation, mainly around the propagation. (Wrong)
2. (Wrong)
3, radiation of radio waves of non-radio equipment mainly refers to industrial, scientific, medical equipment, etc. (Right)
3, radiation of radio waves of non-radio equipment mainly refers to industrial, scientific, medical equipment. (Right)
4, the generation of radio waves must first produce high-frequency electromagnetic oscillation, is to produce a "carrier wave", and then want to transmit the information added to the process of radio slang called "demodulation". (Wrong)
5, sensitivity is an important parameter to measure the receiver's ability to receive weak signals. (Right)
6, in case of emergency endangering people's lives and property safety, you can temporarily use the unauthorized use of radio equipment, but should be promptly reported to the radio administration. (Right)
7, radio stations (stations) deactivated or withdrawn, do not have to go through the relevant procedures in the original approval body. (Wrong)
8, the radio station (station) set up in accordance with the law, the radio administration shall protect its use of frequencies from harmful interference. (Right)
9, interference caused by the interference station neighboring channel power falls into the passband of the receiving neighboring channel receiver, known as neighboring channel interference. (Right)
10. Interference caused by harmonics or spurious radiation from the transmitter within the passband of the received useful signal is called out-of-band interference. (Yes)
11, two or more signals in the receiver and transmitter of the nonlinear transmission circuit intermodulation, resulting in the useful signal frequency close to the combination of frequencies, the resulting interference is called intermodulation interference. (Yes)
12, Electromagnetic Interference (EMI) of the Chinese meaning of electromagnetic interference. (Yes)
13, electromagnetic pollution, also known as spectrum pollution or electrical noise pollution. It is characterized by the field force of the electromagnetic field, and the nature of electric noise, power density and frequency and other factors are closely related. (Right)
14, "small sound point, big sound point" is not a radio direction finding term. (Wrong)
15, 2-meter band radio direction finding operating frequency between 144-146 MHz. (Right)
16, when the atmosphere or the ionosphere appeared inhomogeneous clumps, radio waves may be these inhomogeneous medium to reflect in all directions, so that part of the energy to reach the receiving point, which is the space wave. (Wrong)
17, in amateur radio communication, the most used is the "sky wave" propagation mode, which is the short-wave long-distance communication necessary conditions. (Right)
18, from the surface of the earth to 1000 kilometers high altitude region known as the atmosphere, the atmosphere can be divided into the troposphere, stratosphere and ionosphere. (Right)
19, the atmosphere above 80 kilometers above the Earth's surface is the ionosphere, the ionosphere can be roughly divided into D, E, F1, F2 four layers. (Right)
20, field strength is short for electric field strength, its unit is microvolts / m (μv / m), for convenience, can also be used dB μv / m (0dB = 1 μv) said. (Yes)
21, for 40W of power, the converted value in dBm units should be (take lg2 = 0.3):
10lg (40W/1mw) = 10lg (40,000) = 10lg4 +10lg10,000 = 46dBm. (Yes)
22, power A is twice as large as power B, then 10lg (A power / B power) = 10lg2 = 3dB. That is, the power of A is 3 dB higher than the power of B. (Right)
23, if the power of A is 46dBm, the power of B is 40dBm, then it can be said that the A is higher than the B by 6 dB. (Right)
24, the Doppler direction system of the direction principle: based on the propagation of the electric wave, encountering In the propagation of electric waves, encountered with its relative movement of the direction-finding antenna, was received by the wave signal Doppler effect, the determination of the Doppler effect produced by the frequency shift, you can determine the direction of the incoming wave. (Right)
25, "Chinese people's *** and State Radio Regulations" is the first administrative regulations governing radio management in China. (Right)
26, radio management is a national behavior, government functions. (Right)
27, any unit or individual can set up the use of radio stations as long as for reasonable purposes and reasons. (Wrong) The correct answer is: any unit or individual to set up the use of radio stations, must submit a written application for approval and apply for a radio license can be used. It is strictly prohibited for any unit or individual to set up and use radio stations without authorization.
28, the use of aircraft, ships or trains on the system radio, must be required to obtain a radio license.
(Right)
29, the use of unauthorized radio transmitting equipment in any case is wrong. (Wrong)
The correct answer is: in case of emergency endangering people's lives and property safety, units and individuals can temporarily use unauthorized radio transmitting equipment, but should be promptly reported to the local radio administration.
30, the protection of spectrum resources, to maintain the order of airwaves, is the unique responsibility of the radio administration. (Wrong)
The correct answer is: any unit or individual has the obligation to protect the radio spectrum resources and maintain airwave order.
31, the radio administration has the obligation to protect legal stations. (Right)
32. When a legal radio station is subjected to harmful interference, the radio administration shall investigate and deal with it in a timely manner. (Right)
33, radio management coordination with the military system is entirely the responsibility of the national radio administration. (Wrong)
The correct answer is: the coordination of radio management with the military system is one of the responsibilities of the local radio administration.
34, a radio station in order to improve signal coverage, the transmitter power from 10KW to 100KW, this behavior is reasonable and legal. (Wrong)
35, radio frequency has both general natural resource properties, but also its own special inherent properties. (Right)
36, the radio management organization in the assignment of frequency, should be based on the corresponding business band of the upper and lower limits to retain a reasonable frequency interval. (Right)
37. In order to improve the utilization rate of spectrum, the radio administration generally adopts the approach of space, time and frequency division for frequency planning and assignment according to the three-dimensional characteristics of spectrum. (Right)
38. Before assigning frequencies, radio administrations generally need to analyze the electromagnetic compatibility of the proposed frequencies and select the best frequency points. (Yes)
39, only through the national radio administration type approval of radio transmitting equipment, can be sold in the domestic market. (Right)
40, non-radio transmitting equipment generated by electromagnetic radiation must comply with national regulations, and shall not cause harmful interference to radio services. (Right)
41. Foreigners who bring satellite phones into the country must report to the national or local radio administration organizations for approval in advance. (Right)
42, without the approval of the national radio administration, any foreign organization or person shall not use electronic monitoring equipment to test the parameters of the airwaves within the territory of China. (Yes)
43. Violation of the radio management regulations cause serious consequences, constituting a crime, may be punished in accordance with the provisions of the Criminal Law. (Yes)
44, is one of the tasks of the radio monitoring stations to test the main technical indicators of radio equipment, is one of the tasks of the radio monitoring stations. (Yes)
45, radio testing includes radio transmitting equipment and non-radio equipment radiating radio waves. (Yes)
46, the development of radio transmitting equipment subject to the approval of the national radio regulatory bodies for approval. (Yes)
47, monitoring frequency occupancy, to provide a technical basis for frequency assignment, is an important task of radio monitoring. (Right)