Tektronix NetTek YBT250, User Manual, Page: 154 / 338

Locating Interference
3- 52
YBT250 Field Transmitter & Interference Tester User Manual
Table 3- 8: cdma2000 and 1xEV-DO PN Scanner measurement
fields
Field Description
Total Power (Io) cdma2000: The received power in the signal
bandwidth (1.23 MHz), in dBm.
1xEV-DO: The total received power in the pilot
intervals of the signal, in the signal bandwidth
(1.23 MHz), in dBm.
PN Offset The PN Offset of each detected forward link pilot,
referenced to the timing input signal. Other detected
pilot PN offsets are assigned relative to the highest
power pilot.
cdma2000: If no timing input signal is available, the
highest-powered pilot is assigned PN offset zero.
1xEV-DO: If the timing input signal is not detected, the
instrument displays the message “ESC/TIMING
Reference Not Detected” and the measurement is the
Total Power (Io) value.
Tau (Chips) The timing error, in PN chips, between the ideal and
measured PN offset starting time.
Ec/Io The relative pilot power, in dB, that is detected at the
corresponding PN offset. It is the ratio of the detected
pilot power at that PN Offset to the total received
power. An Ec/Io value of --10 dB indicates that the
pilot at this PN offset contains one tenth of the total
received power.
cdma2000: Ec/Io values less than --20 dB are usually
caused by system noise, and can be disregarded.
Ec The absolute power level of the detected pilot at the
indicated PN Offset, in dBm.
For cdma2000 standards, look for only one or two signals to have
high Ec/Io (> --10 dB) values. All other detected signals should have
Ec/Io values from 5 to 10 dB less than the high signal values to
avoid interference. If there are three or more signals of high and