Freedom R8100 SERIES, Руководство оператора

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Deviation (RF Zone display)
Displays the positive peak FM frequency deviation of the received modulated carrier (i.e. from the
Frequency Error mean). See negative peak frequency deviation with Display Zone Bar Graphs.
2.2.7.3.1.2 PROJECT 25 Zone
Test Pattern (P25 submenu)
Provides selection for one of 4 TIA/EIA-102.CAAA compliant predefined test patterns for BER testing
of a P25 radio in monitor mode as shown in Figure 2.2.7.3.1.2-1. The following patterns are available:
Figure 2.2.7.3.1.2-1 Test Pattern submenu in P25 Monitor mode
1011 Hz Tone – The standard tone framed test pattern of the 1011 Hz vocoder tone.
Calibration (Tone 5%) –The test pattern derived from the standard 1011 Hz Tone test pattern 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.
Monitor Modulation Type (P25 submenu)
Select the expected type of modulation of the received signal to be analyzed: C4FM, LSM, or WCQPSK.
The type specified is used in the Display Zone to enable selection of the Constellation Plot for complex
modulation types (LSM and WCQPSK); it is also used by the Eye Diagram for horizontal positioning.
Modulation Fidelity (P25 Zone display)
Modulation Fidelity (FSK error) represents how accurate a P25 transmitter reproduces an ideal theoretical
modulation waveform. The measurement is performed by first removing frequency error and symbol
deviation gain error from the received signal then computing the RMS difference between the deviation
of the resulting signal at each symbol decision point and the ideal deviations of those symbols; there
should be no bit errors. On the R8100 this is computed over a 72 symbol interval and reported as an RMS
error in % relative to the mean deviation across symbols.
NAC (P25 Zone display)
The Network Access Code, displayed as hexadecimal 000 to FFF, decoded from the P25 embedded
signaling data in the voice frames of the radio or system under test. NAC is digital ID information
equivalent to CTCSS/PL and CDCSS/DPL of analog FM radio systems. The R8100 can receive
transmissions from a radio under test programmed with any NAC but the radio requires the R8100 to
transmit the specific NAC programmed into the radio. See “Copy NAC to Generator” to configure the
R8100 to transmit back to that radio.