This standard specifies the definitions, requirements and test methods, inspection rules and marking, packaging, transportation and storage requirements for wireless paging system equipment. This standard applies to the development and production of wireless paging system equipment and serves as the technical basis for the formulation of product standards. GB/T 15938-1995 General Specification for Wireless Paging System Equipment GB/T15938-1995 Standard download decompression password: www.bzxz.net

ICS33.040.60
National Standard of the People's Republic of China
GB/T15938—1995
General specification for equipment of radio paging system
General specification for equipment of radio paging system Issued on 1995-12-21
State Administration of Technical Supervision
Implementation on 1996-08-01
GB/T15938—1995
This standard is proposed by the Ministry of Electronics Industry of the People's Republic of China. This standard is under the jurisdiction of the Standardization Research Institute of the Ministry of Electronics Industry.
The drafting units of this standard are Tianjin Optoelectronic Communication Company of the Ministry of Electronics Industry and the National Radio Monitoring Center. The main drafters of this standard are Zhao Guolai, Qi Fei, Feng Zhike, Li Dazhi, Qin Yuhua, Chen Xiasheng and Qiu Guoqun. I
1 Scope
National Standard of the People's Republic of China
General specification for equipment of radio paging system
General specification for equipment of radio paging systemGB/T15938—1995
This standard specifies the definitions, requirements and test methods, inspection rules and marking, packaging, transportation and storage requirements for radio paging system equipment.
This standard applies to the development and production of radio paging system equipment and serves as the technical basis for the formulation of product standards. 2 Referenced standards
The provisions contained in the following standards constitute the provisions of this standard through reference in this standard. When this standard is published, the versions shown are valid. All standards will be revised, and parties using this standard should explore the possibility of using the latest versions of the following standards. GB191—85 Packaging, storage and transportation pictorial marking
GB2423.1—89 Basic environmental test procedures for electric and electronic products Test A: Low temperature test method GB2423.2-89 Basic environmental test procedures for electric and electronic products Test B: High temperature test method GB2423.3—81 Basic environmental test procedures for electric and electronic products Test Ca: Steady-state damp heat test method GB2423.8—81
Basic environmental test procedures for electric and electronic products Test Ed: Free fall test method GB2423.10—81 Basic environmental test procedures for electric and electronic products Test Fc: Vibration test method GB2828—87 Batch inspection counting procedure and sampling table (applicable to inspection of continuous batches) Periodic inspection counting sampling procedure and sampling table (applicable to inspection of production process stability) GB 2829-87
GB9410—88General technical specification for mobile communication antennasGB/T14013—92Transport packaging for mobile communication equipmentGB15540—1995Technical requirements and measurement methods for electromagnetic compatibility of land mobile communication equipmentGB/T15844.3—1995Reliability requirements and test methods for mobile communication FM radiotelephones3 Definitions
This standard adopts the following definitions.
3.1Radio paging systemRadiopagingsystemA wireless selective calling system that broadcasts messages in one direction without voice. 3.2Pager
A selective calling receiver suitable for personal use. 3.3Reference modulating signalreferencemodulatingsignalThe reference modulating signal is a set of 101010.repetitive signals generated by a standard encoder. Approved by the State Bureau of Technical Supervision on December 21, 1995 and implemented on August 1, 1996
4 System composition and functions
4.1 System composition
GB/T15938—1995
The main equipment of the system consists of a control terminal, a transmitter, an antenna and a pager. 4.1.1 Single base station system composition
The composition of a single base station system is shown in Figure 1.
Public telephone conversion network
Transmitter
Figure 1 Single base station system composition
4.1.2 Multi-base station system composition
The composition of a multi-base station system is shown in Figure 2.
During public telephone communication
4.2 System functions
The system should have the following functions:
Single call: one-way call to a certain pager;
Control excitation end
Transmitter
Transmitter
Figure 2 Composition of multi-base station system
Group call: simultaneous call to a group of pagers with the same address code; Paging: after completing a certain paging, automatically add the paging within the set time; Timed call: call the pager at the time agreed in advance by the holder and the paging station. 5 Requirements
5.1 General requirements
5.1.1 Appearance
The surface of each device of the wireless paging system should be evenly coated, free of rust, mildew, and mechanical damage, and the text and symbols should be clear. 5.1.2 Structure
GB/T15938—1995
The structure of each device of the wireless paging system should be firm and reliable, easy to use and maintain, and the external dimensions should meet the requirements of the product standards. 5.1.3 Volume and weight
The design of the pager should consider small volume and light weight as much as possible. 5.2 Safety requirements
5.2.1 Insulation resistance
The insulation resistance of the wireless paging system control terminal and transmitter should not be less than 2MQ after the constant humidity and heat test. 5.2.2 Dielectric strength
The input terminal of the wireless paging system control terminal and transmitter power supply and the casing should be able to withstand 1500V AC voltage for 1min, and no arcing or breakdown should occur. 5.2.3 Leakage current
The leakage current between the input terminal and the housing of the radio paging system control terminal and transmitter power supply is: AC: not more than 0.7mA (peak);
DC: not more than 2mA.
5.3 Performance requirements
5.3.1 Transmitter performance requirements
5.3.1.1 Carrier output power
Carrier output power level: 1W5W, 25W, 50W, 100W, error is ±1dB. 5.3.1.2 Working frequency band
Working frequency band: 160MHz, 280MHz, 410MHz. 5.3.1.3 Channel spacing
Channel spacing: 25kHz.
5.3.1.4 Frequency tolerance
Frequency tolerance shall be in accordance with the provisions of Table 1.
Working frequency band
Single base station
Multiple base stations
5.3.1.5 Transmit frequency deviation
Transmit frequency deviation: ±4.5kHz.
5.3.1.6 Spurious emission
Transmitter under reference modulation signal modulation: 160
Frequency tolerance
3×10-6
1×10-7
When the carrier output power is greater than 25W: the spurious emission power should be 70dB lower than the carrier power; when the carrier output power is less than or equal to 25W: the spurious emission power should be less than 2.5μW. 5.3.1.7 Adjacent channel power
2×10-6
When the transmitter is modulated by the reference modulation signal, the average power falling into the 16kHz bandwidth of any adjacent channel should be 70dB lower than the carrier power.
5.3.1.8 Output impedance
The output impedance is 502.
5.3.1.9 Start-up time
The start-up time is less than or equal to 100ms.
5.3.2 Pager performance requirements
5.3.2.1 Sensitivity
GB/T15938—1995
Free space sensitivity is less than or equal to 10μV/m. 5.3.2.2 Adjacent channel selectivity
Adjacent channel selectivity is greater than or equal to 60dB.
5.3.2.3 Spurious response suppression
Spurious response suppression is greater than or equal to 60dB. 5.3.2.4 Image suppression
Image suppression is greater than or equal to 55dB.
5.3.2.5 Intermodulation response suppression
Intermodulation response suppression is greater than or equal to 55dB. 5.3.2.6 Co-channel interference suppression
Co-channel interference suppression is greater than or equal to -8dB. 5.3.2.7 Volume
Single tone: greater than 75dB (at 30cm);
Polyphonic tone: greater than 70dB (at 30cm).
5.3.2.8 Current consumption
When the battery voltage is 1.5V, the current consumption shall be in accordance with the provisions of Table 2. Table 2 Current consumption
Working status
Digital pager
5.3.3 Pager function requirements
5.3.3.1 The pager should have the following functions
a) initialization requirements;
b) service area indication,
c) lighting function;
d) character and page turning display;
e) repeat call display,
f) tone function display,
g) memory identification display;
h) receiving error message display;
i) message storage capacity;
i) receiving message unread prompt;
k) battery low voltage warning function;
Chinese character pager
《100
1) multiple address code.
5.3.3.2 Optional functions
a) vibration function,
b) time reporting function.
5.3.4 Control terminal performance requirements
5.3.4.1 Message signal
GB/T15938—1995
The message signal is the CCIRI number, the frequency tolerance is 1X10-5, the high level amplitude is (12±0.5)V or (8±0.5)V, and the low level amplitude is (—12±0.5)V or (0.5±0.5)V. 5.3.4.2 Control signal
The control signal level amplitude of the transmitter output is (12±0.5)V or (8±0.5)V, and the control signal level amplitude of the transmitter output is (-12±0.5)V or (0.5±0.5)V. 5.3.5 Functional requirements of control terminal
5.3.5.1 Functions that control terminal should have
a) Message length of control terminal:
1) The message length of digital pager is not less than 20 characters; 2) The message length of Chinese character pager is specified by product standards. b) Control terminal query function;
c) Control terminal statistics function;
d) Control terminal billing function.
5.3.5.2 Optional function
Automatic paging function.
5.3.6 Electrical performance requirements of antenna
5.3.6.1 Working frequency band
Working frequency: 160MHz, 280MHz, 410MHz5.3.6.2 Antenna gain
Antenna gain is specified by product standards.
5.3.6.3 Voltage Standing Wave Ratio (VSWR)
The voltage standing wave ratio is less than or equal to 1.5
5.3.6.4 Rated power
The rated power shall be in accordance with the provisions of 2.2.7 of GB941088. 5.3.6.5 Rated voltage
The rated voltage shall be specified by the product standard.
5.3.6.6 Bandwidth
Bandwidth shall be specified by the product standard.
5.3.6.7 Input impedance
The input impedance is 502.
5.4 Transmitter and control terminal power adaptability requirements 5.4.1 When the power supply voltage (a.c. 220V) of the transmitter changes by no more than 10% of the nominal value, the deviation value of the transmitter carrier output power is not allowed to exceed the nominal value by 3dB.
2 When the control terminal power supply voltage (a.c220V) changes no more than 10% of the nominal value, the control terminal performance shall meet the requirements of 5.3.4.
5.5 Environmental requirements
5.5.1 Temperature
GB/T15938—1995
The operating temperature and storage temperature of each device in the system shall be in accordance with the provisions of Table 3. The duration of high and low temperature tests is 2h (or 16h). Table 3 Operating and storage temperatures of each device Equipment name
Control terminal
Transmitter
Pager
5.5.2 Constant damp heat
Celsius: (40±2)℃;
Relative humidity: 90%~95%
Duration: 24h,
Recovery time: 4h.
Working low temperature
-10±3
—40±3
Storage low temperature
—40±3
-10±3
-50±3
Working high temperature
Storage high temperature
When conducting intermediate measurements of low temperature, high temperature and constant humidity and heat tests, the allowable limits of degradation in basic electrical performance of each equipment are as follows: a) The transmitter carrier output power shall not exceed 3dB of the power measured at normal temperature; b) The transmitter frequency tolerance shall comply with 5.3.1.4; c) The decrease in pager sensitivity to the measured value at normal temperature shall not be greater than 6dB; d) The control terminal performance shall comply with the requirements of 5.3.4. 5.5.3 Vibration (sinusoidal)
Vibration frequency: 10Hz~35Hz;
Frequency tolerance: ±1Hz;
Displacement amplitude (single amplitude): 0.75mm, vibration time: 30min.
5.5.4 Free fall of pager
Drop height: 1m;
Number of drops: 2 times.
5.5.5 Simulated transportation
Test bench: Simulated transportation test bench;
Vibration mode: broadband random vibration;
Simulated transportation test time: 30min.
5.5.6 Antenna wind load
Wind speed: 36.9m/s.
5.5.7 Antenna rain
Rain volume: 1mm/min~2mm/min;
Time: 2h.
5.6 Reliability
The average trouble-free working time of each device in the wireless paging system shall be specified by the product standard, and its value shall not be lower than the value specified in GB/T15844.3.
5.7 Electromagnetic compatibility
According to the requirements of the second part of GB15540-1995, it shall be specifically specified by the product standard. 6
6 Test method
6.1 Test conditions
GB/T15938-1995
Unless otherwise specified, all tests and measurements in this standard shall be carried out under the following conditions: 6.1.1 Environmental conditions
Centerology: 15℃~35℃,
Relative humidity: 45%~75%;
Pressure: 85kPa~106kPa.
6.1.2 Power supply conditions
Current: 220V±10%,
Frequency: (50±1)Hz.
6.1.3 Instrument requirements
The accuracy of the measuring instrument shall meet the measurement requirements of the equipment under test, and shall generally be at least one level higher than the measured parameters. It shall be calibrated in accordance with relevant metrological regulations to ensure that it is within the validity period. 6.2 General inspection
6.2.1 Visual inspection of 5.1.1. 6.2.2 Visual inspection of 5.1.2. 6.3 Safety
6.3.1 Insulation resistance measurement
After the constant humidity and heat test, turn the transmitter power switch and the control terminal power switch to the ON position respectively, apply a 500V DC voltage between the input end of the power line and the housing, and after stabilization for 1 minute, the insulation resistance value between the power line and the housing shall meet the requirements of 5.2.1.
6.3.2 Measurement of dielectric strength
Put the transmitter power switch and the control terminal power switch in the ON position respectively, apply 1500V AC voltage between the input end of the power line and the housing, and keep the test voltage for 1 minute after gradually increasing to the specified value. Observe the entire test process, which should meet the requirements of 5.2.2. 6.3.3 Measurement of leakage current
Input 1.1 times the nominal working voltage to the transmitter and the control terminal respectively, turn the power switch to ON, and after stable operation, use an ammeter to measure the leakage current between the input end of the power line and the housing, and the value should meet the requirements of 5.2.3. 6.4 Electrical performance measurement
6.4.1 Transmitter performance measurement
6.4.1.1 Carrier output power
a) Connect the equipment as shown in Figure 3;
Power meter
Figure 3 Output carrier power measurement block diagram
b) Turn on the transmitter, do not modulate the transmitter, and record the value displayed on the power meter. The value should meet the requirements of 5.3.1.1. 6.4.1.2 Frequency tolerance
a) Connect the equipment according to Figure 4;
Encoderwww.bzxz.net
Transmitter
Batch left with a flower device
Frequency tolerance measurement block diagram
GB/T15938—1995
b) Turn on the transmitter, the transmitter is not modulated, adjust the attenuator value appropriately, and record the frequency count value, which should meet the requirements of 5.3.1.4. 6.4.1.3 Transmitter frequency deviation
a) Connect the equipment according to Figure 4;
b) Turn on the encoder and transmitter, keep the encoder output low level, adjust the attenuator value appropriately, and record the frequency count value, which should be the transmitter nominal frequency f. Add the transmitter frequency deviation ±4.5kHzc) Keep the encoder output high level, record the frequency count value, which should be the nominal frequency f of the transmitter. Subtract the transmit frequency deviation ±4.5kHz.
6.4.1.4 Spurious emission
a) Connect the equipment according to Figure 5,
Terminal code
Transmitter
Derivation, consumption
Figure 5 Spurious emission measurement block diagram
Pre-harmonic analyzer
b) Turn on the transmitter, the transmitter is not modulated, adjust the attenuator value appropriately, and record the carrier frequency level. At the same time, measure in the frequency band of 30~2000MHz (except the transmitter operating frequency and the power of the adjacent channel), and record the maximum spurious emission level, the value of which should meet the requirements of 5.3.1.6,
c) The encoder outputs the reference modulation signal. Same as above b, and record the maximum spurious emission level value, the value of which should meet the requirements of 5.3.1.6. 6.4.1.5 Adjacent channel power
a) Connect the equipment as shown in Figure 6, and the test receiver outputs an intermediate frequency signal.
Ai RF transmitter
b) The encoder outputs a reference modulation signal;
Auxiliary transmitter/amplifier
Test receiver
Figure 6 Block diagram of adjacent channel power measurement
Electrical indicator
c) Adjust the test receiver to the nominal frequency of the transmitter and adjust the attenuator number. value to stabilize the input level of the test receiver, and record the attenuator value at this time as P, in dB; d) Adjust the test receiver to the adjacent channel frequency of the transmitter, change the attenuator value to keep the level indicator value unchanged, and record the attenuator value as Q, in dB;
e) The difference between the P value and the Q value should meet the requirements of 5.3.1.7; f) Measure the power of another adjacent channel in the same way, and its value should meet the requirements of 5.3.1.7. 6.4.1.6 Start-up time
a) Connect the circuit according to Figure 7, adjust the attenuator value appropriately and keep the transmitter in the standby state; 8
Shu code decoder
Transmitter
GB/T15938—1995
Root combiner
Display adapter
Figure 7 Start-up time measurement block diagram
Power supply
b) The encoder outputs the modulated signal, and the transmitter changes from the standby state to the transmitting state. Record the oscilloscope The time required for the power meter reading to meet the transmitter power requirement from the moment the transmission is turned on to the moment the envelope displayed on the oscilloscope reaches 70.7% of its stable value. The time value should meet the requirements of 5.3.1.9. 6.4.2 Pager Performance Measurement
6.4.2.1 Sensitivity
a) Connect the equipment according to Figure 8;
Encoder
Signal Source
Pager
Figure 8 Sensitivity Measurement Block Diagram
b) Turn on the encoder and signal signal source, pager. Adjust the signal source frequency to be consistent with the pager receiving frequency, with a frequency deviation of ±4.5kHz; c) Keep the encoder sending five-digit digital information or 20-digit Chinese character information each time, and output the same address code information as the pager; d) Adjust the signal source output level from low to high. If the pager can receive correctly three times in a row or the encoder can receive four out of five messages correctly. Under this condition, the output level of the signal source is the lowest, record this level value, e) Rotate the pager under test 45° clockwise in turn, and repeat d above, record the output level values ​​of the signal sources in the remaining seven directions in turn,
f) The average value of the eight directions is A, and converted into microvolt/meter, and its value should meet the requirements of 5.3.2.1. 6.4.2.2 Adjacent channel selectivity
a) According to Figure 8, the forward sensitivity reference value of the pager in the transverse electromagnetic wave room is measured to be U; b) Connect the equipment according to Figure 9, and set the combined network loss value to L, 9
GB/T15938—1995
T优倍专
fe± ark Hs
汇个网统
af=±a.5 kH
Figure 9 Adjacent channel selectivity measurement block diagram
Momoyama Tower City
Hand-held pager
c) Adjust the signal source to be consistent with the receiving frequency f of the pager, and the frequency deviation △f1 is ±4.5kHz; adjust the output level of the signal source to U+3dB;
d) Adjust the frequency of the interference signal source to f+25kHz, the frequency deviation △f2 is ±3.0kHz, and the frequency of the modulated audio signal generator is 400Hz;
e) The encoder outputs the address code information and five-digit information or 20-digit Chinese character information of the pager each time; f) Adjust the output level of the interference signal source. If the pager cannot receive correctly three times in a row or cannot receive four times of five messages correctly, under this condition, record the maximum output level value C of the interference signal source, in dB; g) The adjacent channel selectivity of the pager is C-U, which should meet the requirements of 5.3.2.2 h) Adjust the frequency of the interference signal source to f. -25kHz, frequency deviation △f2 is ±3.0kHz, modulation signal frequency is 400Hz; i) is the same as above e), f), g).
6.4.2.3 Spurious response suppression
a) Same as 6.4.2.2a, b, c,
b) Adjust the frequency of the interference signal source to one of the spurious response frequencies, the frequency deviation Af2 is ±3.0kHz, and the modulation signal frequency is 400Hzs
c) The encoder outputs the address code information and five-digit information or 20-digit Chinese character information of the pager each time; d) Adjust the output level of the interference signal source. If the pager cannot receive correctly for three consecutive times or cannot receive five messages correctly for four times, under this condition, record the maximum output level value D of the interference signal source, the unit is dBe) The spurious suppression of the pager is DU, which should meet the requirements of 5.3.2.3; f) Measure the spurious response suppression indicators of different spurious response frequencies respectively, and the values ​​should meet the requirements of 5.3.2.3. 6.4.2.4 Image suppression
a) Same as 6.4.2.2a), b), and c),
b) Adjust the frequency of the interference signal source to one of the image frequencies, the frequency deviation Af2 is ±3.0kHz, and the modulation signal frequency is 400Hz; c) The encoder outputs the address code information and five-digit information or 20-digit Chinese character information of the pager each time; d) Adjust the output level of the interference signal source. If the pager cannot receive correctly three times in a row or cannot receive five messages correctly four times, under this condition, record the maximum output level value E of the interference signal source, in dB; e) The image suppression of the pager is E-U, which should meet the requirements of 5.3.2.4; f) Measure the image suppression indicators of different image frequencies respectively, and their values ​​should meet the requirements of 5.3.2.4. 6.4.2.5 Intermodulation response suppression
a) Same as 6.4.2.2a);
b) Connect the test system according to Figure 10, and set the converging network loss value to L; 106 Startup time
a) Connect the circuit according to Figure 7, adjust the attenuator value appropriately and keep the transmitter in the standby state; 8
Shu code decoder
Transmitter
GB/T15938—1995
Root combiner
Display adapter
Figure 7 Startup time measurement block diagram
Power supply
b) The encoder outputs the modulated signal. At this time, the transmitter changes from the standby state to the transmitting state. Record the oscilloscope from the transmitting state to the transmitting state. The time required for the power meter reading to meet the transmitter power requirement from the moment of switching on until the envelope displayed on the oscilloscope reaches 70.7% of its stable value shall meet the requirements of 5.3.1.9. 6.4.2 Pager Performance Measurement
6.4.2.1 Sensitivity
a) Connect the equipment according to Figure 8;
Encoder
Signal Source
Pager
Figure 8 Sensitivity Measurement Block Diagram
b) Turn on the encoder, signal source, Pager. Adjust the signal source frequency to be consistent with the pager receiving frequency, with a frequency deviation of ±4.5kHz; c) Keep the encoder sending five-digit digital information or 20-digit Chinese character information each time, and output the same address code information as the pager; d) Adjust the signal source output level from low to high. If the pager can receive correctly three times in a row or the encoder can receive four out of five messages correctly. Under this condition, the output level of the signal source is the lowest, record this level value, e) Turn the pager under test 45° clockwise in turn, and repeat the above d. Record the output level values ​​of the signal sources in the remaining seven directions in turn.
f) The average value of the eight directions is A and converted into microvolt/meter. Its value should meet the requirements of 5.3.2.1. 6.4.2.2 Adjacent channel selectivity
a) Measure the forward sensitivity reference value of the pager in the transverse electromagnetic wave room according to Figure 8. U; b) Connect the equipment according to Figure 9. Set the combined network loss value to L. 9
GB/T15938—1995
T优倍专
fe± ark Hs
汇个网统
af=±a.5 kH
Figure 9 Adjacent channel selectivity measurement block diagram
Momoyama Tower City
Hand-held pager
c) Adjust the signal source to be consistent with the receiving frequency f of the pager, and the frequency deviation △f1 is ±4.5kHz; adjust the output level of the signal source to U+3dB;
d) Adjust the frequency of the interference signal source to f+25kHz, the frequency deviation △f2 is ±3.0kHz, and the frequency of the modulated audio signal generator is 400Hz;
e) The encoder outputs the address code information and five-digit information or 20-digit Chinese character information of the pager each time; f) Adjust the output level of the interference signal source. If the pager cannot receive correctly three times in a row or cannot receive four times of five messages correctly, under this condition, record the maximum output level value C of the interference signal source, in dB; g) The adjacent channel selectivity of the pager is C-U, which should meet the requirements of 5.3.2.2 h) Adjust the frequency of the interference signal source to f. -25kHz, frequency deviation △f2 is ±3.0kHz, and modulation signal frequency is 400Hz; i) is the same as above e), f), and g).
6.4.2.3 Spurious response suppression
a) Same as 6.4.2.2a, b, c,
b) Adjust the frequency of the interference signal source to one of the spurious response frequencies, the frequency deviation Af2 is ±3.0kHz, and the modulation signal frequency is 400Hzs
c) The encoder outputs the address code information and five-digit information or 20-digit Chinese character information of the pager each time; d) Adjust the output level of the interference signal source. If the pager cannot receive correctly for three consecutive times or cannot receive five messages correctly for four times, under this condition, record the maximum output level value D of the interference signal source, the unit is dBe) The spurious suppression of the pager is DU, which should meet the requirements of 5.3.2.3; f) Measure the spurious response suppression indicators of different spurious response frequencies respectively, and the values ​​should meet the requirements of 5.3.2.3. 6.4.2.4 Image suppression
a) Same as 6.4.2.2a), b), and c),
b) Adjust the frequency of the interference signal source to one of the image frequencies, the frequency deviation Af2 is ±3.0kHz, and the modulation signal frequency is 400Hz; c) The encoder outputs the address code information and five-digit information or 20-digit Chinese character information of the pager each time; d) Adjust the output level of the interference signal source. If the pager cannot receive correctly three times in a row or cannot receive five messages correctly four times, under this condition, record the maximum output level value E of the interference signal source, in dB; e) The image suppression of the pager is E-U, which should meet the requirements of 5.3.2.4; f) Measure the image suppression indicators of different image frequencies respectively, and their values ​​should meet the requirements of 5.3.2.4. 6.4.2.5 Intermodulation response suppression
a) Same as 6.4.2.2a);
b) Connect the test system according to Figure 10, and set the converging network loss value to L; 106 Startup time
a) Connect the circuit according to Figure 7, adjust the attenuator value appropriately and keep the transmitter in the standby state; 8
Shu code decoder
Transmitter
GB/T15938—1995
Root combiner
Display adapter
Figure 7 Startup time measurement block diagram
Power supply
b) The encoder outputs the modulated signal. At this time, the transmitter changes from the standby state to the transmitting state. Record the oscilloscope from the transmitting state to the transmitting state. The time required for the power meter reading to meet the transmitter power requirement from the moment of switching on until the envelope displayed on the oscilloscope reaches 70.7% of its stable value shall meet the requirements of 5.3.1.9. 6.4.2 Pager Performance Measurement
6.4.2.1 Sensitivity
a) Connect the equipment according to Figure 8;
Encoder
Signal Source
Pager
Figure 8 Sensitivity Measurement Block Diagram
b) Turn on the encoder, signal source, Pager. Adjust the signal source frequency to be consistent with the pager receiving frequency, with a frequency deviation of ±4.5kHz; c) Keep the encoder sending five-digit digital information or 20-digit Chinese character information each time, and output the same address code information as the pager; d) Adjust the signal source output level from low to high. If the pager can receive correctly three times in a row or the encoder can receive four out of five messages correctly. Under this condition, the output level of the signal source is the lowest, record this level value, e) Turn the pager under test 45° clockwise in turn, and repeat the above d. Record the output level values ​​of the signal sources in the remaining seven directions in turn.
f) The average value of the eight directions is A and converted into microvolt/meter. Its value should meet the requirements of 5.3.2.1. 6.4.2.2 Adjacent channel selectivity
a) Measure the forward sensitivity reference value of the pager in the transverse electromagnetic wave room according to Figure 8. U; b) Connect the equipment according to Figure 9. Set the combined network loss value to L. 9
GB/T15938—1995
T优倍专
fe± ark Hs
汇个网统
af=±a.5 kH
Figure 9 Adjacent channel selectivity measurement block diagram
Momoyama Tower City
Hand-held pager
c) Adjust the signal source to be consistent with the receiving frequency f of the pager, and the frequency deviation △f1 is ±4.5kHz; adjust the output level of the signal source to U+3dB;
d) Adjust the frequency of the interference signal source to f+25kHz, the frequency deviation △f2 is ±3.0kHz, and the frequency of the modulated audio signal generator is 400Hz;
e) The encoder outputs the address code information and five-digit information or 20-digit Chinese character information of the pager each time; f) Adjust the output level of the interference signal source. If the pager cannot receive correctly three times in a row or cannot receive four times of five messages correctly, under this condition, record the maximum output level value C of the interference signal source, in dB; g) The adjacent channel selectivity of the pager is C-U, which should meet the requirements of 5.3.2.2 h) Adjust the frequency of the interference signal source to f. -25kHz, frequency deviation △f2 is ±3.0kHz, and modulation signal frequency is 400Hz; i) is the same as above e), f), and g).
6.4.2.3 Spurious response suppression
a) Same as 6.4.2.2a, b, c,
b) Adjust the frequency of the interference signal source to one of the spurious response frequencies, the frequency deviation Af2 is ±3.0kHz, and the modulation signal frequency is 400Hzs
c) The encoder outputs the address code information and five-digit information or 20-digit Chinese character information of the pager each time; d) Adjust the output level of the interference signal source. If the pager cannot receive correctly for three consecutive times or cannot receive five messages correctly for four times, under this condition, record the maximum output level value D of the interference signal source, the unit is dBe) The spurious suppression of the pager is DU, which should meet the requirements of 5.3.2.3; f) Measure the spurious response suppression indicators of different spurious response frequencies respectively, and the values ​​should meet the requirements of 5.3.2.3. 6.4.2.4 Image suppression
a) Same as 6.4.2.2a), b), and c),
b) Adjust the frequency of the interference signal source to one of the image frequencies, the frequency deviation Af2 is ±3.0kHz, and the modulation signal frequency is 400Hz; c) The encoder outputs the address code information and five-digit information or 20-digit Chinese character information of the pager each time; d) Adjust the output level of the interference signal source. If the pager cannot receive correctly three times in a row or cannot receive five messages correctly four times, under this condition, record the maximum output level value E of the interference signal source, in dB; e) The image suppression of the pager is E-U, which should meet the requirements of 5.3.2.4; f) Measure the image suppression indicators of different image frequencies respectively, and their values ​​should meet the requirements of 5.3.2.4. 6.4.2.5 Intermodulation response suppression
a) Same as 6.4.2.2a);
b) Connect the test system according to Figure 10, and set the converging network loss value to L; 102a)b), c),
b) Adjust the frequency of the interference signal source to one of the image frequencies, the frequency deviation Af2 is ±3.0kHz, and the modulation signal frequency is 400Hz; c) The encoder outputs the address code information and five-digit information or 20-bit Chinese character information of the pager each time; d) Adjust the output level of the interference signal source. If the pager cannot receive correctly three times in a row or cannot receive four times out of five messages correctly, under this condition, record the maximum output level value E of the interference signal source, in dB; e) The image suppression of the pager is E-U, which should meet the requirements of 5.3.2.4, f) Measure the image suppression indicators of different image frequencies respectively, and their values ​​should meet the requirements of 5.3.2.4. 6.4.2.5 Intermodulation response suppression
a) Same as 6.4.2.2a);
b) Connect the test system according to Figure 10, and set the convergence network loss value to L; 102a)b), c),
b) Adjust the frequency of the interference signal source to one of the image frequencies, the frequency deviation Af2 is ±3.0kHz, and the modulation signal frequency is 400Hz; c) The encoder outputs the address code information and five-digit information or 20-bit Chinese character information of the pager each time; d) Adjust the output level of the interference signal source. If the pager cannot receive correctly three times in a row or cannot receive four times out of five messages correctly, under this condition, record the maximum output level value E of the interference signal source, in dB; e) The image suppression of the pager is E-U, which should meet the requirements of 5.3.2.4, f) Measure the image suppression indicators of different image frequencies respectively, and their values ​​should meet the requirements of 5.3.2.4. 6.4.2.5 Intermodulation response suppression
a) Same as 6.4.2.2a);
b) Connect the test system according to Figure 10, and set the convergence network loss value to L; 10
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