Telecom Technical Specifications




старонка4/8
Дата канвертавання25.04.2016
Памер1.14 Mb.
1   2   3   4   5   6   7   8

5.3 Cordless Phone function in connecting to PSTN

5.3.1 Radio frequency requirement


The frequency below 80 MHz of the low power duplex cordless telephone shall be adapted by DGT (as table 4 and table 5).

Table 4 The operation frequency for 1.6 / 49MHz cordless phone

Channel

Base station frequency(MHz)

Portable frequency(MHz)

Receive

Transmission

Transmission

Receive

1

49.830

1.665

49.830

1.665

2

49.830

1.695

49.830

1.695

3

49.830

1.725

49.830

1.725

4

49.830

1.755

49.830

1.755

5

49.830

1.785

49.830

1.785

6

49.845

1.665

49.845

1.665

7

49.845

1.695

49.845

1.695

8

49.845

1.725

49.845

1.725

9

49.845

1.755

49.845

1.755

10

49.845

1.785

49.845

1.785


Table 5 The operation frequency for 46 / 49MHz cordless phone

Channel

Portable(Transmission frequency)

Base station(Transmission frequency)

1

49.670 MHz

46.610 MHz

2

49.845 MHz

46.630 MHz

3

49.860 MHz

46.670 MHz

4

49.770 MHz

46.710 MHz

5

49.875 MHz

46.730 MHz

6

49.830 MHz

46.770 MHz

7

49.890 MHz

46.830 MHz

8

49.930 MHz

46.870 MHz

9

49.990 MHz

46.930 MHz

10

49.970 MHz

46.970 MHz

5.3.2 Security code requirement


The security measures of probability unauthorised use should be less than 1 in 1000 for both base and handset unit.

A declaration of conformance to this requirement should be provided by the supplier.



5.3.3 Transmitter requirement

5.3.3.1 Carrier frequency


Requirement: The carrier frequency is the ability of the transmitter to maintain an assigned carrier frequency ( The shift should be less than ±500Hz ).

Purpose: Test carrier frequency of transmitter to avoid interfering to other electrical equipments.

Test Method:

1. Carrier frequency test configuration as Fig.29.

2. Test method of measuring carrier frequency


    1. Operate the equipment in standby transmitter conditions.

    2. Record the carrier frequency of the transmitter as MCF.

    3. Calculate the frequency error by the following:

Frequency error = ACG – MCF.

MCF is the Measured Carrier Frequency in Hz.

ACF is the Assigned Carrier Frequency in Hz.

Loop Simulator

EUT

RF Stanrdard Load for TE

RF Counter

Figure 29 Carrier frequency test configuration
Test equipment:


  1. Loop Simulator.

  2. RF. Stanrdard Load for TE.

  3. RF Counter.



5.3.3.2 Modulation sensitivity (Use for Base station only)


Requirement: While input voice-band signal via loop simulator to TE, the signal level of standard test modulation produced should be -12 ±3dB.(During testing, any microphone auto-functions should be disable)

Purpose:The Modulation sensitivity is testing the Audio Input signal produce ±3KHz Deviation is to modulate its sensitivity.

Test method:

1. Modulation sensitivity test configuration as Fig.30.

2. Test method of measuring Modulation sensitivity


  1. Apply a 1000Hz tone from the audio generator and adjust is output level until 60% of rated system deviation is reached.

  2. Record the audio generator output level as the Modulation sensitivity.

Test equipment:

  1. Loop Simulator.

  2. Audio Frequency Signal Generator.

  3. Standard R.F. Load for TE.

  4. Modulation Meter.


Audio Frequency

Signal Generator

Loop Simulator

Base Unit of TE

RF Stanrdard Load for TE

Modulation Meter

Figure 30 Modulation sensitivity test configuration

5.3.3.3 Audio distortion


Requirement : The audio distortion is the voltage ratio, usually expressed as a percentage of the rms value of the undesired signal of the transmitter's demodulated output tot the rms value of the complete signal at the output of the transmitter's demodulator. (specification:< 5%).

Purpose: The Audio Input signal produce ±3KHz Deviation is to modulate its distortion in order to assure its quality.

Test Method:

1. Audio distortion test configuration as Fig. 31.

2. Test method of measuring Audio distortion


  1. Set Audio Frequency at 1000Hz and adjust the output level to produce 60% of the rated system deviation.

  2. Measure and record the audio distortion of the transmitter.

Audio Frequency

Signal Generator

Loop Simulator

EUT

RF Stanrdard Load for TE

Modulation Meter

Distortion Meter


Figure 31 Audio distortion test configuration

Test equipment:


  1. Loop Simulator.

  2. Standard R.F. Load for TE.

  3. Audio Frequency Signal Generator.

  4. Modulation Meter.

  5. Distortion Meter.



5.3.4 Receiver requirement

5.3.4.1 Useable sensitivity


Requirement: The level of receiver input signal at a specified frequency with specified modulation which will result in the standard SINAD at the output of the receiver. Specification:<2.0μV.

Purpose:Testing the ability of Receiving signal for the transmitter.

Test method:

1. Usable sensitivity test configuration as Fig. 32.



RF Signal Generator.

EUT


AF- Load

SINAD Meter



Figure 32 Usable sensitivity test configuration


2. Test method of measuring Usable sensitivity

  1. Apply a standard input signal to the receiver input terminals.

  2. Adjust the output level of RF signal generator to let the receiver reach the standard 12 dB SINAD.

  3. Such RF signal level is useable sensitivity.

Test equipment:

  1. RF Signal Generator.

  2. AF-Load.

  3. SINAD Meter.



5.3.4.2 Useable bandwidth


Requirement: The useable Bandwidth is the input signal frequency displacement that reduces the SINAD produced by a signal 6dB in the reference sensitivity of the standard 12 dB SINAD. Specification:Over±500 Hz.

Purpose:The Useable Bandwidth is testing shift frequency of Base Unit for receiving in order to reduce the sensitivity of Bandwidth by 6 dB.

Test method:

1. Useable bandwidth test configuration as Fig. 33.

2. Test method of measuring Useable bandwidth


  1. Sending a standard input signal from RF signal generator to the input of receiver.

  2. Adjust RF signal generator and adjust its level to a value that produces 12 dB SINAD reference sensitivity.

  3. The output level of RF signal generator is the level of sensitivity (Reference Sensitivisty).

  4. Increase the signal level by 6dB.

  5. Increase the input signal frequency until the 12 dB SINAD reference sensitivity is obtained Record this frequency as FM.

  6. SINAD reference sensitivity is abtained. Record this frequency ad FL.

  7. Calculate the frequency differences by the following:

GDIFF1= FH - nominal frequency.

GDIFF2= nominal frequency –FL.

The smaller of GDIFF1, or GDIFF2 is the useable Bandwidth.

Test equipment:



  1. RF Signal Generator.

  2. AF-Load.

  3. Audio Frequency Distortion Meter.

RF Signal Generator.


EUT


AF- Load

SINAD Meter

Figure 33 Useable bandwidth test configuration



5.3.4.3 Audio distortion


Requirement: The audio distortion is the voltage ratio, usually expressed as a percentage of the rms value of the undesired signal to the rms value of the complete signal at the output of the receiver. (Specification: < 5%).

Purpose: The Audio distortion is testing the distortion rate of Receiving signal in order to assure its quality.

Test method:


  1. Audio distortion test configuration as Fig. 34.

  2. Test method of measuring Audio distortion

  1. RF Signal Generator apply a standard input signal to the receive input terminals.

  2. Measure and record the audio distortion readings.


RF Signal Generator.

EUT


AF- Load

Distortion meter


Figure 34 Audio distortion test configuration

Test equipment:


  1. RF Signal Generator.

  2. AF-Load.

  3. Distortion Meter.



5.3.4.4 Signal and noise ratio


Requirement: The ratio of the rated output power to the residual output power in the absence of modulation, measured at standard input signal level. Specification: > 40dB.

Purpose:The signal and Noise Ratio is testing the ratio between signal and noise of output power in the absence of modulation circumstance.

Test method:


  1. Signal and noise ratio test configuration as Fig. 35.

  2. Test method of measuring Signal and noise ratio

  1. Apply a standard input signal to the receiver.

  2. Record the audio output level as V1.

  3. Remove the modulation in the RF Sigal Generator and record the audio output level as V2.

  4. Calculated as signal to Noise Ratio=20log(V1/V2).

RF Signal Generator.


EUT


AF- Load

SINAD Meter

Figure 35 Signal and noise ratio test configuration

Test equipment:


  1. RF-Signal Generator.

  2. AF-Load.

  3. SINAD Meter.


5.3.4.5 Adjacent channel rejection


Requirement: The adjacent channel rejection is the ratio of the level of an adjacent input signal that causes the SINAD produced by a wanted signal 3 dB in excess of the reference sensitivity to be reduced to the standard 12 dB SINAD to the reference sensitivity. Specification:> 45dB.

Purpose:The Adjacent channel Rejection is the testing the Receiving of transmitter is to avoid to the possibility of rejection from adjacent channel.

Test method:

1. Adjacent channel rejection test configuration as Fig. 36.

RF Signal Generator A

RF Mixer

EUT


AF- Load


SINAD Meter

RF Signal Generator B

Figure 36 Adjacent channel rejection test configuration


2. Test method of measuring Adjacent channel rejection

    1. Power off the RF - Signal Generator B.

    2. RF - Signal Generator A send out the standard nput signal.

    3. Record the signal level P0 of EUT receiving reference sensitivity.

    4. Increase the input signal level 3dB.

    5. Power on the RF - Signal Generator B and apply an input signal modulated with 400 Hz at 60% of the maximum permissible frequency deviation to adjacent channel.

    6. Adjust the signal level between one channel and its adjacent channel to reach the reference sensitivity of receiver signal frequency, record their channel levels as P1 and P2.

    7. Calculate the Adjacent channel rejection:

The adjacent channel rejection high = P1 – P0.

The adjacent channel rejection low = P2 – P0.

Test equipment:


  1. RF-Signal Generator  2.

  2. RF Mixer.

  3. SINAD Meter.

  4. AF-Load.



5.3.4.6 Spurious response rejection


Requirement: Spurious response rejection is to keep the spurious response signal less than input signal of receiver to avoid the spurious response. Specification:>35 dB.

Purpose:The Spurious response rejection is testing the receiving of TE is to avoid to the possibility of Interference from unwanted signal in output port.

Test method:


  1. Spurious response rejection test configuration as Fig. 37.


RF Signal Generator A



RF Mixer

EUT


AF- Load


SINAD Meter

RF Signal Generator B

Figure 37 Spurious response rejection test configuration




  1. Test method of Spurious response rejection.

    1. Power off the RF - Signal Generator B.

    2. RF - Signal Generator A send out the standard nput signal.

    3. Record the signal level P0 of EUT receiving reference sensitivity.

    4. Increase the input signal level 3dB.

    5. Power on the RF - Signal Generator B and apply an input signal modulated with 400 Hz at 60% of the maximum permissible frequency deviation to adjacent channel.

    6. Adjust the Spurious response frequency from receiver 1/2 middle frequency to double receiver frequency (except the receiver frequency in ±100kHz), adjust the Spurious response frequency to the maximum effect.

    7. Adjust the input signal level of Spurious respons to reach the reference sensitivity and record the signal level of Spurious respons as P1.

    8. Calculate the Spurious respons rejection = P1 - P0

Test method:

  1. RF-Signal Generator  2.

  2. RF Mixer.

  3. SINAD Meter.

  4. AF-Load.



5.3.5 Radiated Field Intensity and Interference test


Requirement: The radiated field intensity at 3 meter distance should be less than 10000μV / m. The radiated field intensity at 3 meter distance of harmonied frequency and unwanted power should be less than the requirements list in the table 6 below:

Purpose:To measure the radiated field intensity of harmonied frequency and unwanted power of cordless telephone handset at transmission and receiving states to prevent the interference.

Test method: According to CNS 13438.

Test equipment: According to CNS 13438.

Table 6


Frequency

(MHz)


Maximum field intensity at 3 m of harmonied frequency (μV/m)

Maximum field intensity at 3 m of unwanted power (μV/m)

25 ~ 88

100

100

88 ~ 216

150

150

216 ~ 1000

200

200



1   2   3   4   5   6   7   8


База данных защищена авторским правом ©shkola.of.by 2016
звярнуцца да адміністрацыі

    Галоўная старонка