Freedom R8100 SERIES, Руководство оператора

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Calibration (Tone 5%) – The test pattern derived from the standard 1011 Hz Tone test pattern used to
verify BER measurements are operating correctly. Every 20th bit is inverted to yield 172 errors out of
3456 bits resulting in a 4.976852% BER.
Standard Tx (O.153/V.52) – The standard transmitter test pattern of continuously repeating 511-bit pseudo
random number sequences based on ITU-T O.153 (formerly CCITT V.52).
Silence – The framed test pattern for silence at the vocoder.
Symbol Rate – The maximum frequency deviation test pattern of a continuously repeating stream of high
deviation symbols (+3, +3, -3, -3, …).
Low Deviation – The test pattern of a continuously repeating stream of low deviation symbols (+1, +1, -
1, -1, …) for a 1/3 maximum frequency deviation.
C4FM Mod Fidelity – The test pattern of a continuously repeating 24 bit sequence (12 symbols) used for
measuring C4FM modulation fidelity (+3, +3, -3, +1, +1, +3, -1, +3, -3, -1, -3, -3).
Two additional TIA/EIA-102.CAAA compliant bit patterns can easily be created for testing a P25 radio
in receive mode by using the procedure below:
1. Set Test Pattern to 1011 Hz Tone.
2. Set Voice Frame Encoder, Status Symbols as specified below.
Note: For compliance the NAC and other voice frame fields should be defaults.
Busy – This test pattern provides channel busy information.
Idle – This test pattern provides channel idle information. Beware that one bit (2374) of this pattern will
differ from TIA/EIA-102.CAAA 1.3.3.6 e) Standard Idle Test Pattern.
Note: These test patterns allow subscriber alignment for Automatic Frequency Control.
Generate Modulation Type (P25 submenu)
Select the desired type of modulation for the generated signal required by the receiver: C4FM, LSM, or
WCQPSK.
Modulation Mode (P25 submenu)
A horizontal submenu provides choice of Off, Continuous, or Burst mode for the selected Test Pattern
modulation. Note: Enabling a test pattern in Generate mode will erase any previously captured Voice
Recordings.
NAC (P25 submenu)
Set the Network Access Code (NAC) to match the radio or system under test in a data entry window. The
range of values is from hexadecimal 000 to FFF. Alpha numeric entries are made using the ▲▼
(Up/Down), and ◄► (Left/Right) keys, numeric keypad, and spin knob. In generate mode, the NAC soft
key is hidden and its display value grayed out for test pattern selections that are not modifiable (e.g.
Calibration).