Download Chill radar user manual. Champaign, IL : Illinois State Water Survey

October 11,1989
Radar-Antenna Control Program
2.2.19. FIELDS * indicates the fields to be selected for possible recording and
display. Reflectivity and normalized coherent power (NCP) are always selected.
Optional fields are:
a. VEL indicates the mean velocity field will be recorded
b. ZDR indicates the ZDR field will also be recorded
c. W2 indicates spectrum width (from R1 and R2) will be recorded
d. Rl indicates the lag 1 correlation field will be recorded
e. R2 indicates the lag 2 correlation field will be recorded
2.2.20. FILTNUM * indicates which ground clutter filter to use. A zero indicates that
no filtering should be done. See the appendix for a table of filter widths available.
2.2.21. FILTEND* indicates the last range gate to be filtered. Any remaining gates
will receive no ground clutter filtering.
2.2.22. BYPASS * indicates the state of the waveguide bypass switch. If set to yes,
the fast polarization switch is bypassed.
Note that while FILTNUM, FILTEND, and BYPASS may be set by the operator to
indicate the current operating state, they currently have no effect as to controlling
the system state. They are recorded on tape. In the future, these items will have a
control function also.
2.2.23. TXPWR * may be set by the operator to the current peak transmit power.
This value is recorded with the data. At some future time, this may be
continuously measured and reported here.
2.2.24. GATES * indicates the number of range gates to be processed when in the
doppler or ZDR mode. This tells the SP20 how many calculations of R0, R1 and
R2 need to be made.
2.2.25. RNGAVG * range averaging option may be set to 2 to allow a 2 bin averaging
to be performed on R0, Rl, and R2, before the final products are calculated. This
doubles the number of independent samples, thus allowing faster antenna rotation.
RNGAVG should be set to 1 to disable range averaging.
2.2.26. SPI * (signal processor initialization) is a string of one or more assignment
statements which will be made when the scan segment is activated. Each
assignment should have the form: :symbol:=vaIue. Multiple assignments are
separated by commas.
2.3. Control Area Parameters:
2.3.1. AZPROGPOS. ELPROGPOS : are the angles the antenna controller maintains
when the azimuth or elevation is "fixed" for the desired scan mode. During the
segment initiation, these programmed positions are set to the AZSTART,
ELSTART values (see 2.2.9) from the new scan segment In scanning modes, the
STEP angle will be added to the fixed angle (ELPROGPOS for PPI,
AZPROGPOS for RHI) at the end of each sweep until the fixed angle crosses a
limit.
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