Q8. What is the purpose of the COVER program?
Q9. What are the limitations of the SSP program?
Q10. What is the major software advantage with the
TESS-NC Transition as compared to the TESS
Q11. Which government environmental software
programs are provided with the TESS-NC?
Q12. What is the purpose of the TESS-NC Unix-based
REFRACTIVE EFFECTS PREDICTION
LEARNING OBJECTIVES: Identify the
purpose of refractive effects prediction
Identify the refractive effects
displays available with the Integrated
Refractive Effects Prediction System (REPS)
and the Advanced Refractive Environmental
Prediction System (AREPS). Describe the
major advantages of AREPS.
Refractive effects prediction programs are
designed to provide Aerographers Mates with the
capability of assessing the refractive effects upon naval
surveillance, communications, electronic warfare, and
weapon-guidance systems. Either historical or real-
time upper-air sounding data is used as input.
INTEGRATED REFRACTIVE EFFECTS
PREDICTION SYSTEM (IREPS)
The first refractive assessment software program
was the Integrated Refractive Effects Prediction System
(IREPS) developed in the late 1970s. IREPS is
designed for use over open ocean areas only. The
program assumes the homogeneity of the atmosphere
(single airmass) based on the input of a single upper-air
sounding. Output options include various refractive
effects products such as electromagnetic propagation
conditions summaries (PCS), radar coverage display
diagrams (COVER), path-loss versus range displays
(LOSS), surface-search radar range tables (SSR), and
Electronic Support Measures (ESM) radar intercept-
range tables. The applications and limitations of these
programs were covered with TESS (3) in the previous
section. Although IREPS is resident software on TESS
(3), it is no longer issued as a stand-alone program. In
addition, most of the products produced by IREPS have
been incorporated into GFMPL.
ENVIRONMENTAL PREDICTION SYSTEM
The most current refractive effects assessment
program is the Advanced Refractive Environmental
Prediction System (AREPS). AREPS computes
basically the same refractive tactical decision aids as
IREPS. However, AREPS uses a more advanced
prediction model that produces more accurate data. The
most significant advantage of AREPS is that it can
produce refractive effects predictions over land using
terrain data obtained from either the National Imagery
and Mapping Agency (NIMA) or the users own sources.
In addition, AREPS is able to evaluate range-dependent
scenarios, and can also compute radar detection ranges
for multiple bearings simultaneously. As of this
writing, users must build their own electromagnetic
riles as there is no electromagnetic data base provided
with the program.
Figure 2-2 is an example of an
AREPS radar coverage diagram. The AREPS Users
Manual, SSC San Diego Technical Document 3028
provides a detailed description of the AREPS program.
AREPS is designed to run using Windows 95
or Windows NT and is normally obtained as part
of the GFMPL NT package. You can also down-
load the AREPS program and the AREPS man-
u a l f r o m t h e S P A W A R S w e b s i t e a t :
http://sunspot.spawar.navy.mil. CD-ROM versions of
AREPS are available from SPAWARS on a request-
Q13. What is the purpose of refractive effects
Q14. What is the most significant advantage of AREPS
DECISION AID (EOTDA)
LEARNING OBJECTIVES: Define the term
Electra-Optics. Identify the purpose of the
Electra-Optical Decision Aid (EOTDA)
Recognize the output options
available from the EOTDA program.