User's Manual Part 2
Processing Algorithms (draft)
RVP8 User’s Manual
April 2003
5–42
5.7.4 Overview of Processing Algorithms
Polarization Modes and Outputs Supported by RVP8
The RVP8 supports four polarization modes summarized in the table below. For each case, the
standard moments (T, Z, V and W) are calculated as well. The notation for the outputs used here
is similar to that in standard usage (e.g., Doviak and Zrnic). However, for LDR we use the
notation LDRH to indicate that this is the LDR for horizontal transmission. The notation RHOH
and PHIH is used to indicate the magnitude and phase of the covariance between the co- and
cross–polarized channels for H transmit.
Case
Transmit Receive Processing
Mode
Polarization Outputs
1 Fixed Horizontal or
Fixed Vertical
Dual-Channel PPP only LDRH RHOH PHIH or
LDRV RHOV PHIV
2 Simultaneous H+V
(STAR Mode)
Dual-Channel PPP or
ZDR for FFT, Ran-
dom Phase and
DPRT1&2
ZDR PHIDP KDP
RHOHV
3 Alternating H/V Single-Channel PPP only ZDR PHIDP KDP
RHOHV
4 Alternating H/V Dual-Channel PPP only LDRH RHOH PHIH
LDRV RHOV PHIV
ZDR PHIDP KDP
RHOHV
Input Receiver Sample Notation
For the discussion of polarization, we will adopt the notation used by Doviak and Zrnic. The
received signal for pulse n from a single range bin shall be denoted as:
s
n
hh
Receive h: Transmit h Horizontal co-polar signal
s
n
vh
Receive v: Transmit h Horizontal cross–polar signal
s
n
vv
Receive v: Transmit v Vertical co–polar signal
s
n
hv
Receive h: Transmit v Vertical cross–polar signal
The pulse index is now indicated by the superscript as opposed to the subscript. The first
subscript indicates the received polarization while the second subscript indicates the transmit
polarization. If the transmit is the same as the received polarization, then this is called the
co–polarized signal. If the transmit and receive are different then this is called the
cross–polarized signal.
These variables are complex and are the same is the “s
n
” notation used earlier, for example we
can write:
s
n
hh
Ą +Ą I
n
hh
Ą )Ą jĄQ
n
hh
to show the relationship to the received I and Q values. Either filtered and unfiltered versions of
the samples can be selected for processing. However, for convenience we will drop the s’
notation for filtered samples.