Volume 3, Number 4

September 2002

Contents

Anti-Jam GPS Part IV 1

FYI 8

News 8

Weaponeering Course 10

Director’s Corner 1

Sensors/Seekers

Course 13

Smart/Precision 

WeaponsCourse 14

Calendar of Events 15

WSTIAC is a DoD Information

Analysis Center Sponsored by the

Defense Technical Information

Center and Operated by IIT

Research Institute

WST

WEAPON SYSTEMS TECHNOLOGY INFORMATION ANALYSIS CENTER

IAC

Anti-Jam GPS Technology 

in Weapon Receivers: 

Part IV: Postscript

by Mark Scott

IIT Research Institute

Introduction

Over the past year, a series of three articles has been published in the WSTIAC newsletter

on anti-jam GPS receivers employed in onboard weapon guidance applications. In parallel with the newsletter articles, WSTIAC has produced a State-of-the-Art Review (SOAR)

on this subject (this report is about to be released: WSTIAC-SOAR-02-01). The series of

articles has been received by the weapons community with great enthusiasm, which has

prompted us, here at WSTIAC, to follow up the series with a postscript article that describes

some of the more refined analytical techniques and results from the SOAR. This article will

assess the effectiveness of reduced track loop bandwidth and adaptive antenna processing (with both C/A and P(Y)-code signals) against the most serious jamming threat (viz.,

wideband noise jammers).

House Keeping

The GPS jamming analysis in the previous articles has been fairly informal and elementary. This section will tighten up the analytical techniques to be used before proceeding.

The nominal minimum GPS receiver base bandwidth of 50 Hz has been used for purposes of calculating noise and jamming interference power levels so far in this series. This

approach was initially adopted for conceptual simplicity. But by this point, the reader is

aware that different GPS functions employ varying bandwidth processes. Sometimes even

the same function employs variable adaptive bandwidth filtering techniques, as in the case

of the carrier/code tracking loops. To avoid the necessity of computing separate interference levels for the multiple bandwidths employed in GPS receivers, it is common to reference such computations to a 1 Hz bandwidth. This approach effectively normalizes signalto-interference power ratio (SIR) calculations across all receiver processes. Accordingly,

hereinafter, all interference (jamming and noise) calculations will be performed as average

power levels per 1 Hz bandwidth, in units of W/Hz or dBW/Hz. These calculations then

represent power spectral densities of the interference, denoted as Nofor receiver thermal

noise, Jofor the jamming signal, and Io = Jo + Nofor the total interference. 4
2

The ratio of total received GPS signal power (S) to the power spectral

density of the total interference (Io = Jo + No) will henceforth be used

as the fundamental measure of GPS receiver performance. This ratio

will be denoted as S/Io or SIRo, measured in units of Hz or dB-Hz. In

the absence of jamming, S/Ioreverts to S/No, the signal power-tonoise power spectral density ratio (or signal-to-noise density ratio for

short). In the literature, S/Nois often referred to as the carrier-to-noise

density ratio, denoted as C/No[Gagliardi, p. 39].

The guaranteed minimum GPS input power levels (Si) for the L1 C/Acode, L1 P(Y)-code, and L2 P(Y)-code signals, are: -160 dBW, -163

dBW, and -166 dBW, respectively. These power levels are valid at the

output terminals of an omnidirectional receive antenna (i.e., at the

receiver input port, or the adaptive antenna processor (AAP) input port,

if AAP is being used − see Figure 1). To carry these signals through the

receiver to the baseband processing level, receiver implementation

losses (Lr) should be deducted from the power levels: Lr = 2 dB was

previously used as a representative value. The signal powers (S) available for the receiver to process are accordingly: -162 dBW (L1 C/Acode); -165 dBW (L1 P(Y)-code); -168 dBW (L2 P(Y)-code).

The receiver's thermal noise power spectral density (No) is given by:

No = k ToF W/Hz (1)

= 10-20 W/Hz

= -200 dBW/Hz

Figure 1. Location of various power levels and ratios in the receive chain − note that insertion of an adaptive antenna processor 

(AAP) effectively moves the receiver input port to the input of the AAP. Insertion of the AAP subsystem provides major 

levels of jamming suppression with only minor elevation in receiver noise figure.

where

k = Boltzmann's constant = 1.38 x 10-23 J/K

To = thermal noise reference temperature

= 290 K

F = receiver noise figure

= 4 dB (representative value used previously)

= 2.51

Representative minimum signal-to-noise density ratios for the three

GPS signals are thus [Kaplan pp. 219-220]:

S/No = S(dBW) - No(dBW/Hz) (2)

= S - No[dB-Hz]

= 38 dB-Hz for L1 C/A-code

= 35 dB-Hz for L1 P(Y)-code

= 32 dB-Hz for L2 P(Y)-code 

Adaptive Antenna

Electronics/Processor

GPS Receiver (Rx)

Channel (Lr = 2 dB)

ü Signal Acquisition

ü Data Demodulation

ü Signal Tracking (Carrier/Code)

GPS Rx Functions

Spread Spectrum

Bandwidth Base Bandwidth

ü Si [dBW]

ü Ji(Rj) [dBW]

ü JSR(Rj) = Ji(Rj) - Si [dB]

S [dBW]

Jo(Rj)

No = kToF

I

o

(Rj) = Jo(Rj) + No

SIRo(Rj) = S - 10 log {I o(Rj)}

SNRo = S - 10 log (No)

[W/Hz]

[dB-Hz]

To Navigation Processor

Note: Rj = slant range between receiver and jammer.

Jamming power level at the receiver is a function of range.

4
3

[W]

4

G

G

4 (R 10 )

P

J (R )

2

raj

3 2 ja

j

jt

i J

π

⋅λ

⋅ ⋅

π⋅ ⋅

=

The jammer-to-signal power ratio at the receiver input is then simply

(see Figure 1 again).

2 SSBW

1

L

1

4

G

G

4 (R 10 )

P

J (R )

r

2

raj

3 2 ja

j

jt

o J

⋅

⋅ ⋅

π

⋅λ

⋅ ⋅

π⋅ ⋅

= (3)

GPS signal[Hz]

SSBW spread spectrum bandwidth of

divisor]

L GPS receiver losses [dimensionlessloss

0.24 m for L2 carrier]

GPS carrier wavelength [0.19 mfor L1carrier;

equation (3)]

of jammer [dimensionless gain factor as used in

G power gain of GPS receiveantenna in direction

gain factor as used in equation (3)]

G power gain of jammer antenna [dimensionless

receiver [km]

R slant range between jammer and GPS

jammer antenna [W]

P jammer transmitter power coupled into

r

raj

ja

j

jt

=

=

=

=

=

=

=

λ

where

If the receiver is employing adaptive antenna processing (AAP), then

an additional factor of one over the level of jamming suppression

(antjs) associated with the AAP must be included in equation (3):

antjs

1

2 SSBW

1

L

1

4

G

G

4 (R 10 )

P

J (R )

r

2

raj

3 2 ja

j

jt

o J

⋅

⋅

⋅ ⋅

π

⋅λ

⋅ ⋅

π⋅ ⋅

= (4)

(5)

The first three factors in equation (4) form the jamming input power

level into the receiver (or into the adaptive processor if AAP is used):

JSR(R ) 10 log [J (R )] S [dB] J = 10 i j − i

The total interference density is given by:

I (R ) 10log [J (R ) N ] [dBW /Hz] o j 10 o J o

o j o j o

= +

(7)

The signal-to-interference density ratio is then given by:

SIR (R ) S I (R ) [dB Hz] o j = − o j − (8)

{ [ ]}

10log (antjs)

JSRth 10 log 2 SSBW 10 10

10

SIR th /10 SNR /10

10

o o

+

= ⋅ −

− −

GPS receivers require the received signal power to exceed interference

power spectral density by certain levels to accomplish signal acquisition and signal tracking (which provides pseudo-range measurements

for the navigation solution). Accordingly, SIRo(Rj), in relation to the

required thresholds, is the fundamental measure of GPS receiver performance in a jamming environment. A representative value for the

SIRothreshold to accomplish the signal acquisition function is SIRoth =

33 dB-Hz. Representative thresholds for signal tracking are SIR oth =

28 dB-Hz (for a 20 Hz bandwidth phase lock carrier tracking loop),

and SIRoth = 19 dB-Hz (for an IMU rate-aided, 2 Hz, reduced bandwidth carrier tracking loop) - [Parkinson/Spilker pp. 254-255 and

Kaplan pp. 221-222].

While attainable SIRo(Rj) is the fundamental measure of AJ receiver

performance, an often quoted AJ metric is the input level of jammerto-signal power ratio (JSR) up to which a receiver can operate (i.e., the

JSR environment at the receiver input). This metric represents an upper

bound threshold or ceiling on the JSR (JSRth) at which a receiver can

operate (i.e., as long as the JSR at the receiver input stays below JSRth,

the receiver can operate). SIRothresholds (in dB-Hz) can be translated into JSR thresholds (in dB) via the following equation [Kaplan p.

221]:

(9)

JSR as a function of range from weapon to jammer, i.e., JSR(Rj), will

be plotted in relation to JSRth in parallel with SIRo(Rj) and SIRoth, to

impart some intuition to the reader with respect to the relationship

between these two AJ receiver performance metrics. The correspondence between the JSR and SIR o

thresholds, in accordance with equation (9), is given in Table 1, for both the C/A and P(Y) codes on the L1

carrier, with varying levels of antenna jamming suppression, for both

signal acquisition and tracking receiver functions.

Note in Table 1 that as the required SIR othreshold value steps down

(from signal acquisition to track or from wideband to narrowband

track), the corresponding value of JSR threshold steps up; i.e., the

receiver becomes less demanding of signal-to-interference density

ratio and hence is more tolerant of jamming. Also note that increasing levels of antenna-based jamming suppression (antjs) add directly

to the receiver's tolerance threshold for JSR environment: adding 20

dBic of antenna jam suppression raises the JSR thresholds by 20 dB.

As identified in Table 1, the JSR tracking threshold of 54 dB, corresponding to the L1 P(Y)-code with no antenna jam suppression and a

narrowband carrier loop, is often quoted as "standard" military GPS

receiver tolerance to jamming (the corresponding "standard" JSR

acquisition threshold is 35 dB). 

(6)

sity of a wideband-jamming signal (Jo) at receiver baseband (see

Figure 1). In Part II of this series, equation (8) gave the total jamming

power in a GPS receiver's base bandwidth (BBW). If BBW is divided

out of this expression, the resulting equation gives jamming power per

unit receiver base bandwidth in units of W/Hz -- this is precisely the

definition of jamming power spectral density (or jamming density for

short):

4
4

The next section will describe how GPS receiver anti-jam features,

quantified in terms of JSR tolerance threshold (JSRth), translate into

ranges of influence for a 10 W wideband noise jammer. This analysis

will also illustrate how increasing levels of jamming suppression reduce

the jammer's range of influence over a weapon's GPS receiver.

Anti-Jam GPS Receiver Performance

This section will translate the SIRo and JSR thresholds, from the previous section, into denial range zones for a 10 W wideband noise jammer. AJ GPS receiver performance, based on adaptive filtering and

antenna processing techniques, will then be applied to illustrate the

resulting reductions in denial range zones for the jammer. The geometry of the analysis scenario is shown in Figure 2, where a GPS guided weapon approaches a single jammer that resides at the origin of a

local coordinate system (Rj = 0). If the weapon is a low flyer, like a

cruise missile, then the slant range from jammer to receiver (Rj) is

approximately equal to the ground range from jammer to receiver

(Rjg).

Pjt = jammer transmit power delivered to

 jammer antenna

 = 10 W

Gja = gain of jammer antenna

 = 1 (0 dBic)

Graj = gain of receive antenna in

 direction of jammer

 = 0.5 (-3 dBi c)

antjs = antenna jam suppression

 = 0 and 26 dBi c

Jammer

R = range from satellite to receiver

Rj = range from jammer to reciever

Rj = 0

Rjg = ground range from jammer to receiver

GPS

Figure 2. Analysis scenario geometry.

The jammer's antenna is assumed to be omni-directional (Gja = 1,

i.e., unit gain or 0 in dBic) for maximum spatial coverage with no

requirement for information on weapon direction of arrival. The nominal gain of the GPS receive antenna (prior to any adaptive antenna

processing) in the direction of the jammer is assumed to be lower than

an omni-directional level (say Graj = 0.5 = -3 dBic). The rationale for

this assumption is that the receive antenna is looking at least somewhat above the horizon for satellites, and the jammer on the ground is

somewhat below the weapon's horizon. Accordingly, receive antenna

gain is typically falling off for low elevation angles, at and below the

horizon.

Other receiver parameter values are identical to those used throughout this series of articles - many of these were identified in the previous

section in preparation for this jamming suppression analysis. The L1

carrier signal will be used throughout the analysis as will a wideband

Gaussian noise jamming signal, matched to the spread spectrum

bandwidth of the code it is targeting (1.023 MHz for C/A-code and

10.23 MHz for P(Y)-code).

0 20 40 60 80 100 120 140 160 180 200

0

1 0

2 0

3 0

4 0

Rj [km]

SIRo(Rj) [dB-Hz]

SIRo Thresholds

-- acquisition

-- track

0 20 40 60 80 100 120 140 160 180 200

2 0

3 0

4 0

5 0

6 0

7 0

Rj [km]

JSR(Rj) [dB]

JSR Thresholds

-- track

-- acquisition

64 km 134 km

GPS Denial Zone Track Only Zone Acquisition & Track Zone

Jammer

Location

JSR Thresholds

-- track 35 dB

-- acquisition 28 dB

SIRo Thresholds

-- acquisition 33 dB-Hz

-- track 28 dB-Hz

Figure 3. Case #1: Pjt = 10 W, L1 C/A-code, WB track loop,

antjs = 0 dBic.

JSRth (dB)

L1 C/A-code

SNRo = 38 dB-Hz

SSBW = 1.023 MHz

L1 P(Y)-code

SNRo = 35 dB-Hz

SSBW = 10.23 MHz

GPS

Receiver

Function

SIRo th

(dB-Hz)

antjs = 0 dBic antjs = 0 dBic antjs = 26 dBic

Signal 

Acquisition 33 28 35* 61

Narrowband

Carrier Track 19 44 54* 80

Wideband

Carrier Track 28 35 44 70

*Standard military GPS receiver (Rx) operational capability in the presence of jamming.

Table 1. Translation of SIRo baseband thresholds into JSR input 

thresholds for various AJ GPS receiver characteristics.

Case # 1

Jammer transmit power = Pjt = 10 W

Signal = L1 C/A-code

Carrier track loop bandwidth = wideband = 20 Hz

Antenna jam suppression = antjs = 0 dBic 4
5

Case # 2

Jammer transmit power = Pjt = 10 W

Signal = L1 C/A-code

* Carrier track loop bandwidth = narrowband = 2 Hz

Antenna jam suppression = antjs = 0 dBic

0 20 40 60 80 100 120 140 160 180 200

0

1 0

2 0

3 0

4 0

Rj [km]

SIRo(Rj) [dB-Hz]

SIRo Thresholds

-- acquisition

-- track

0 20 40 60 80 100 120 140 160 180 200

2 0

3 0

4 0

5 0

6 0

7 0

Rj [km]

JSR(Rj) [dB]

JSR Thresholds

-- track

-- acquisition

21 km 134 km

Track Only Zone Acquisition & Track Zone

GPS Denial Zone

JSR Thresholds

-- track 44 dB

-- acquisition 28 dB

SIRo Thresholds

-- acquisition 33 dB-Hz

-- track 19 dB-Hz

Figure 4. Case #2: Pjt = 10 W, L1 C/A-code, NB track loop, 

antjs = 0 dBic.

The narrowed track loop bandwidth reduces the 10 W jammer's range

of influence from 64 km down to 21 km with respect to L1 C/A-code

signal tracking. While this represents a considerable improvement in

receiver tracking performance, no improvement is realized in signal

acquisition range. Furthermore, the 21 km track denial zone may still

be unacceptable in many weapon applications. Accordingly, additional AJ features are required to reduce even this 10 W jammer's

range of influence. The next obvious move is to switch from C/A-code

operation to the P(Y)-code. This is the preferred code for military operation anyway, with code encryption to prevent "spoofing" by false signal deception jammers. In Case # 3 we switch to L1 P(Y)-code signals.

Case # 3

Jammer transmit power = Pjt = 10 W

*Signal = L1 P(Y)-code

Carrier track loop bandwidth = narrowband = 2 Hz

Antenna jam suppression = antjs = 0 dBic

In this case, the narrow bandwidth track loop from Case #2 is maintained, but we shift from the C/A-code to the P(Y)-code signal. The

wider spread spectrum bandwidth of the P(Y)-code (factor of 10)

dilutes the jammer's power spectral density at baseband resulting in a

significant reduction in the jammer's range of influence for both signal

acquisition and tracking. Acquisition denial range is reduced from

134 to 85 km; track denial range is reduced from 21 to 10 km. (See

Figure 5).

While utilization of the P(Y)-code represents a significant improvement

in a receiver's resistance to jamming, the 0-10 km track denial zone

and 10-85 km acquisition denial zone are still unacceptable for most

weapon applications, especially in light of the small size of this jammer. An array of a large number of such small jammers is tactically

feasible and could create a sizable GPS "keep-out" zone. AJ measures

that go beyond utilization of P(Y)-code signals and narrow track loop

bandwidth are necessary. These additional AJ measures lead into

adaptive antenna processing techniques in the next case.

Figure 3 shows a considerable range of influence for even this very low

power jammer against an unprotected C/A-code receiver channel. At

ranges greater than 134 km from the jammer, normal GPS operation

occurs, in terms of both acquiring and tracking satellite signals. This

is evidenced, in the plots, by the fact that SIRo(Rj) > both the track and

acquisition thresholds for Rj > 134 km, and by the fact that JSR(Rj) <

both the track and acquisition thresholds on allowable jamming environment. Within 134 km of the jammer, SIRo

(Rj) falls below the 33

dB-Hz acquisition threshold requirement and JSR (Rj) rises above the

allowable jamming-to-signal acquisition environment of 28 dB.

Accordingly, the L1 C/A-code signal cannot be acquired within 134

km of this 10 W jammer.

This baseline scenario establishes a low power jammer's range of

influence on C/A-code signal acquisition and tracking, with a wideband carrier loop and no antenna-based jamming suppression. These

conditions represent an unprotected receiver on every count. This

level of jammer can be packaged in a briefcase portable size.

However, lock can be maintained on L1 C/A-code signals already

being tracked, down to a range of 64 km. At this point, SIRo(Rj) falls

below the required wideband track threshold of 28 dB-Hz and JSR (Rj)

rises above the allowable upper threshold of 35 dB. Signal lock is then

lost along with all GPS operation for the L1 C/A-code signal. The 10

W jammer thus denies all GPS operation on L1 C/A-code signals out

to a radius of 64 km, for the Case #1 receiver configuration.

The only changed parameter here, in comparison to case # 1, is the

carrier loop bandwidth. By designing a narrower, IMU-aided, carrier

tracking loop, or by allowing the receiver to adaptively reduce this

bandwidth in the sensed presence of jamming, a lower SIRotrack

threshold requirement of 19 dB-Hz is achieved (compared to 28 dBHz in Case #1). The corresponding allowable JSR ceiling is 44 dB

(compared to 35 dB in Case #1). This enables the receiver to maintain lock on tracked L1 C/A-code signals down to a range of 21 km.

(See Figure 4).

4

WSTIAC Newsletter 4th Quarter 2002
6

Case # 4

Jammer transmit power = Pjt = 10 W Signal = L1 P(Y)-code

Carrier track loop bandwidth = narrowband = 2 Hz

*Antenna jam suppression = antjs = 26 dBic

This case applies 26 dBic of jamming suppression via an adaptive

antenna pattern (i.e., 26 dB of jamming attenuation relative to an

isotropic circularly polarized antenna reception pattern). This jamming

attenuation is relatized through a combination of null steering in the

direction of the jammer and limited beam forming in the direction of

the satellite(s). This implementation of adaptive antenna processing is

known as adaptive array processing (AAP) and utilizes multiple antenna elements (as few as 2 elements for first tier capability) to form and

steer nulls toward a jammer(s), while maintaining or increasing gain in

the directions of satellites. An alternative simpler single aperture adaptive antenna processing technique is that of polarization nulling. Pol0 1 2 3 4 5 6 7 8 9 1 0

1 5

2 0

2 5

3 0

3 5

Rj [km]

SIRo(Rj) [dB-Hz]

SIRo Thresholds

-- acquisition

-- track

0 1 2 3 4 5 6 7 8 9 1 0

5 0

6 0

7 0

8 0

9 0

Rj [km]

JSR(Rj) [dB]

JSR Thresholds

-- track

-- acquisition

0.5 km 4.25 km

Track Only Zone Acquisition & Track Zone

GPS Denial Zone

SIRo Thresholds

-- acquisition 33 dB-Hz

-- track 19 dB-Hz

JSR Thresholds

-- track 80 dB

-- acquisition 61 dB

Figure 6. Case #4: Pjt = 10 W, L1 P(Y)-code, NB track loop, 

antjs = 26 dBic.

0 10 20 3 0 40 50 6 0 70 80 90 100

0

1 0

2 0

3 0

4 0

Rj [km]

SIRo(Rj) [dB-Hz]

SIRo Thresholds

-- acquisition

-- track

0 10 20 3 0 40 50 6 0 70 80 90 100

3 0

4 0

5 0

6 0

7 0

Rj [km]

JSR(Rj) [dB]

JSR Thresholds

-- track

-- acquisition

10 km 85 km

Track Only Zone Acquisition & Track Zone

GPS Denial Zone

SIRo Thresholds

-- acquisition 33 dB-Hz

-- track 19 dB-Hz

JSR Thresholds

-- track 54 dB

-- acquisition 35 dB

Figure 5. Case #3: Pjt = 10 W, L1 P(Y)-code, NB track loop, 

antjs = 0 dBic.

arization nulling adaptively develops a mismatch between the polarizations of the receive antenna and the jamming radiation to attenuate

the interfering signal. Levels of attenuation consistent with the current

case (viz., 26 dBic) have been demonstrated with polarization nulling

and much higher with AAP [Baeder et.al. pp. 1,4,10-12].

Figure 6 illustrates that the 26 dBic of antenna jamming suppression

adds directly to the JSR thresholds that the receiver can tolerate as an

input jamming environment. The 35 dB acquisition threshold fromcase # 3 goes to 35 + 26 = 61 dB; the 54 dB tracking threshold from

Case #3 goes to 54 + 26 = 80 dB. These threshold changes drastically reduce the range influence of this low power wideband jammer.

The addition of 26 dBic of antenna jamming suppression enables the

weapon's GPS receiver to acquire signals to within about 4 km of the

jammer and track signals to within 0.5 km of the jammer. This level of

GPS receiver AJ performance is adequate for most weapon applications. Thus, the conditions of Case 4 identify GPS receiver AJ features

adequate to largely nullify the influence of a single 10 W wideband

jammer: P(Y)-code receiver with aided, narrowband carrier tracking

and at least 26 dBic of antenna-based jamming suppression.

Multiple jammers or larger jammers will require more AJ capability in

the GPS receiver.

Summary and Conclusions

Table 2 summarizes the analysis results from the previous section on

the performance of anti-jamming (AJ) GPS techniques in reducing the

effective range of wideband noise jammers (jamming bandwidth

As a post script to Case #3, the level of jam resistance afforded by

this receiver configuration (P(Y)-code with narrowband aided carrier

tracking) is often quoted as "standard" military GPS capability. This

standard GPS capability is typically quantified in terms of the JSR

thresholds of 54 and 35 dB, corresponding to the allowable input

jamming environments for the signal tracking and acquisition functions respectively.

4
7

GPS Denial Ranges due to Jamming (km)

1 10 W C/A WB 0 dBic 35 dB

2 10 W C/A NB 0 dBic 44 dB

3 10 W P(Y) NB 0 dBic 54 dB

4 10 W P(Y) NB 26 dBic 80 dB

10 20 30 40 50 60 70 80 90 100 110 120 130 140

Antenna Jam

Suppression

J/S Track

Threshold

Case

No

Jam

Power 1 Code TrackBW2

Table 2. AJ GPS PERFORMANCE IN REDUCING EFFECTIVE RANGE OF JAMMERS

1

 Effective Isotropic Radiated

Power (EIRP): product of net

power delivered to antenna &

antenna gain.

2

 Carrier loop bandwidth (BW):

WB = wideband = 20 Hz

NB = narrowband = 2 Hz

10 20 30 40 50 60 70 80 90 100 110 120 130 140

L

E

G

E

N

D

GPS denial zone: jammer inhibits

receiver from tracking & acquiring

signals.

Max track denial range.

Track only zone: jammer inhibits receiver from acquiring

signals but receiver can maintain established signal

tracks.

Max acquisition range.

Full GPS

operation

beyond this

range.

matched to spread spectrum bandwidth of the GPS signals). Cases 1-

4 are for a 10 W jammer. Cases 1 and 2 employ the L1 C/A-code

signal while cases 3 and 4 employ the L1 P(Y)-code signal. Case 1

uses a wideband carrier tracking loop (20 Hz) which has low tolerance

to jamming environments, while the other cases employ narrowband

(2 Hz), inertially aided carrier tracking loops, which are able to track

GPS signals in higher levels of jamming (up to 54 dB JSR compared to

only 35 dB JSR for the wideband loop). Case 4 utilizes AAP jamming

suppression.

The combination of signal code employed, track loop bandwidth, and

level of antenna-based jamming suppression, in Table 2, combine to

determine the GPS receiver's tolerance to jamming. This tolerance is

quantified in terms of how high a jamming-to-signal power ratio (J/S

= JSR) environment the receiver can experience and still maintain lock

on GPS satellite signals it is tracking. The level of J/S environment that

the receiver can tolerate for signal tracking is indicated in the "J/S

Track Threshold" column in Table 2. Note in Table 2 that the greater

the level of J/S environment that the receiver can tolerate, the less the

range of influence that the jammer has over the GPS receiver, both in

terms of acquiring and tracking signals.

Inspection of Table 2 shows that GPS receivers employing: (1) direct

use of P(Y)-coded signals; (2) narrowband tracking loops; and (3)

antenna-based interference suppression, can virtually null out the

effective range of influence of the level of jamming considered in this

article (10 W). This allows precision guided munitions full access to

GPS navigation signals at arbitrarily short offsets from this threat jammer.

One of the key features of this article is the explanation of how a GPS

receiver's antijam capability, specified in terms of an allowable J/S (or

JSR) environment at the receiver's input, translates into the range of

influence a given size jammer (in terms of effective radiated power) will

have in denying the receiver the ability to acquire and track GPS satellite signals.

Some other points to note in regard to the anti-jam performance

analysis carried out within this article are as follows:

i) Only single jammer scenarios were considered in this article.

Multiple or larger jammers will require more receiver protection.

ii) All analysis performed in this article assumes onmidirectional jammer antennas. Use of omni antennas simplifies an adversary's employment of jammers, with no requirement for information on the direction

of approach of GPS guided weapons. Higher gain antennas would

yield an increased range of jammer influence over GPS receivers at the

cost (to the adversary) of more complicated employment.

iii) All analysis performed in this article used the minimum GPS signal

power levels assuming: minimum satellite transmit power; maximum

satellite to receiver range; and worst case antenna geometry-gain.

More typical GPS signal power levels are normally anywhere from several to 6 or 7 dB higher, depending on satellite status, age, and range. 

Higher signal power contributes directly to reducing a jammer's range

of influence; however, it's probably both valid and prudent to plan on

worst case signal levels for the following reasons: an aging satellite

constellation; delays in launching new satellites due to budget constraints; and twelve channel receivers (that attempt to acquire and

track low elevation - long range satellites) becoming the norm. 

In conclusion, jamming represents a serious threat to unprotected GPS

receivers in precision guided munition (PGM) applications for the current configuration of GPS. Low power satellite transmitters and lofty

orbits put the GPS signal power density at a big disadvantage compared to even small earth-bound jammers, despite spread spectrum

signal processing gains inherent in the GPS signal structure. From all

the potential techniques of deception, narrowband, and wideband

jamming, wideband noise jammers represent the most serious nearterm threat that is feasible for adversaries to field in significant numbers −and this fact has been widely advertised on the internet and elsewhere. GPS jammer assembly instructions and off-the-shelf units are

available for modest investments from foreign sources. (there is evidence that Russia has helped Iraq with GPS jamming--see

Bachmann/Caussade, pp.1-2.) These jammers could easily degrade

precision munition accuracy from the 10 m or better accuracy associated with GPS guidance, out to the tens to hundreds of meters associated with uncorrected inertial guidance (depending on weapon flight

duration).

ECCM techniques exist that are capable of largely mitigating the nearterm GPS jamming threat. Receiver based filtering techniques can be 

4

WSTIAC Newsletter 4th Quarter 2002
8

Better Weather Forecasts with GPS

A new globe-spanning satellite network will furnish round-theclock weather data, monitor climate change, and improve

space weather forecasts by intercepting signals from the Global

Positioning System (GPS). The system will use atmosphereinduced changes in the radio signals, to infer the state of the

atmosphere above some 3,000 locations every 24 hours.

The satellite network, called COSMIC is now being developed

through a U.S.-Taiwan partnership.

"The increased coverage will improve weather forecasts by providing data where there previously was none or not enough,"

says Ying-Hwa Kuo, project director for the Constellation

Observing System for Meteorology, Ionosphere and Climate

(COSMIC), also called ROCSAT-3 in Taiwan. COSMIC's satellites will investigate the atmosphere using radio occultation.

Each satellite will intercept a GPS signal after it passes through

(is occulted by) the atmosphere close to the horizon. Such a

path brings the signal through a deep cross-section of the

atmosphere. Variations in electron density, air density, temperature, and moisture bend the signal and change its speed. By

measuring these shifts in the signal, scientists can determine the

atmospheric conditions that produced them. COSMIC will complement the existing and planned U.S. meteorological satellites.

For additional information see:

http://www.cosmic.ucar.edu/index.html

http://genesis.jpl.nasa.gov/html/missions/cosmic.html

COSMIC System Description

http://www.cosmic.ucar.edu/science/related_papers/Rocken362.pdf

Publications on GPS applications, Planetary occultations, GPS occultations can be found at http://genesis.jpl.nasa.gov/html/publications/pub_index.html 

FYI....

New from the Center for Strategic and International Studies (CSIS)

Iraq's Military Capabilities in 2002,A Dynamic Net Assessment by

Anthony Cordesman. This report provides a timely dynamic net

assessment of Iraq's military capabilities as of August 2002. A great

deal is known about Iraqi military capabilities and probable behavior,

as well as about the military capabilities and behavior of its potential

enemies. The list of potential contingencies is limited, and there are

often severe constraints on the options available to Iraq and its opponents. As a result, it is possible to make educated "guesstimates" as to

Iraq's capabilities relative to most key scenarios, and about the

strengths and weaknesses of its position in most contingencies. In this

report, a noted expert on Iraq and the Middle East lays out those

guesstimates. For additional information see

http://www.csis.org/pubs/2002_iraq.htm

A Brief History of the Airborne Laser

On July 18, 2002, the airborne laser made its first flight out of

McConnell Air Force Base. An Air Force Research Laboratory Directed

Energy Fact sheet gives a brief synopsis of more than 20 years of R&D

culminating in this event.

http://www.de.afrl.af.mil/Factsheets/ABLHistory.html. ♦

very effective against narrowband jamming and should be implemented in weapon receivers. However, the large quantum leaps in AJ GPS

receiver performance are realized via antenna-based measures. 

Polarization nulling and especially spatial filtering, based on adaptive

array processing, can provide significant suppression of fairly extensive

wideband jamming environments.

This AJ protection for GPS guidance receivers comes at an increased

cost per weapon that varies from a fraction to a multiple of the cost of

the receiver being protected (depending on the level of immunity

afforded and quantity buy of the systems involved). Planned improvements in the GPS space segment in the coming years include a new

military code and increased satellite effective radiated power that will

greatly enhance the jamming immunity of the overall navigation system. Until these upgrades reach IOC, maintaining the effectiveness of

GPS guidance functions in precision munition applications will depend

on effective ECCM implemented in the weapon receiver and especially in the receiver's antenna. ♦

References:

Bachmann, S. and Caussade, J.; “Russia Helps Iraq with GPS

Jamming;” GPS for Air and Space Power Newsletter; 4 Sep 2000.

Baeder, B.T., et. al.; “GPS AJ Testing of the ERI ISU for Application to

the ATACMS Missile System;” www.ericorp.com.

Gagliardi, R.; Introduction to Communication Engineering; New York,

NY; John Wiley & Sons, Inc.; 1978.

Kaplan, E.D.; Understanding GPS--Principles and Applications;

Boston, MA; Artech House; 1996.

Parkinson, B.W. and Spilker, J.J.; GPS: Theory and Applications, Vol

1; Washington DC, AIAA, Inc; 1996.

About the Author

Mark Scott received B.S. and M.S. degrees in Electrical Engineering

from Michigan State University in 1974 and 1976 respectively. From

1977 to 1982 he was employed by the Instrument Division of Lear

Siegler, Inc., working on tactical avionics systems. From 1982 to 1984

he was employed by IIT Research Institute, performing countermeasure/counter-countermeasure (CM/CCM) analyses on air defense

radars. From 1984 to 1987 he was with Harris Corporation working

on airborne data links, after which he rejoined IITRI. His current

research interests include sensor/countermeasure performance analysis, signal processing, and sensor fusion for smart weapons, multisensor seekers, survivability suites, and C3I applications. Mr. Scott is a

member of IEEE, the IEEE Aerospace and Electronic Systems Society,

and the Association of Old Crows.

Editor’s Note: This concludes the series on Anti-jam GPS. Many of

our readers have responded enthusiastically to Mark Scott’s articles.

The contents of our newsletter are cleared for public release, and an

electronic version is available at:

http://wstiac.iitri.org/NewsAndEvents/Wstiac_NewsLetter.html.

The State of the Art Review mentioned in the introduction is currently in

review and will be published shortly. The SOAR addresses topics

detailed this series of articles, however it does so in greater detail with

specific weapon design issues in mind. It will be released as a limited

distribution publication available to DoD components and their contractors. 

4
9

DARPA DEMONSTRATES AFFORDABLE

MOVING SURFACE TARGET ENGAGEMENT

USING JDAM WEAPON

The Defense Advanced Research Projects Agency (DARPA) Affordable

Moving Surface Target Engagement (AMSTE) program has for the first

time demonstrated the ability to precisely engage moving surface targets with a modified Joint Direct Attack Munition (JDAM).

The JDAM precision-guided weapon has previously been used very

effectively against fixed targets. AMSTE techniques and technologies

will permit inventory weapons such as the JDAM to be employed in a

new role to precisely engage moving surface threats.

On August 22, 2002, the AMSTE team successfully demonstrated the

ability to track a moving target from long range and to use this tracking information to continuously redirect a JDAM weapon in flight to

attack that target. This flight test was conducted at the Air Force test

range at Eglin Air Force Base, Fla.. In the demonstration, real-time

information on a moving target was developed from standoff radar

sensors, and the resulting tracking data was relayed from a Joint STARS

aircraft directly to a modified JDAM in flight. The modified JDAM consisted of a standard 2,000 pound inert bomb body with the standard

JDAM tail kit modified to include a low-cost data link. The JDAM was

released from an F-16 fighter at an altitude of 20,000 feet and was

directed to a specific target moving in a column of traffic crossing the

range at 18 miles per hour. The modified JDAM corrected its aim point

continuously in flight and impacted well within the AMSTE-specified

accuracy of 10 meters circular error probable (CEP).

“This flight test validates the AMSTE goal of modifying inventory unitary weapons, originally designed for the precision engagement of

fixed targets, to provide a new capability for stand-off precision

engagement of moving targets,” explains Stephen Welby, Deputy

Director of the DARPA Information Exploitation Office. “An objective

AMSTE system would allow multiple, networked weapons and sensors

to precisely track, target and destroy high-value, moving, surface targets in real-time. This is a powerful transformational capability for U.S.

warfighters. AMSTE provides the technology to permit the accurate

delivery of low-cost, precision-guided munitions from long range with

the potential to eliminate the sanctuary of movement for our enemies.”

Additional AMSTE weapon demonstrations will continue this

September, when the AMSTE team will attempt more complex moving

target engagement scenarios at the Naval Weapons Center, China

Lake, Calif. These flight experiments intend to demonstrate multiple,

simultaneous JDAM weapon deliveries and integrate AMSTE technologies with the Joint Stand-off Weapon (JSOW). Future tests will present

more challenging target scenarios and will assess the ability of featureaided tracking tools to support long-term track maintenance for highvalue targets throughout the targeting cycle.

DARPA’s AMSTE program is developing a network-centric targeting

approach that will couple standoff airborne radar sensors and low-cost

weapons in a real-time engagement network. Under the AMSTE

approach, data from multiple airborne ground moving target indicator (GMTI) radar sensors are fused to provide weapons with real-time

target position updates while in-flight. AMSTE will provide a new strike

capability to engage moving surface threats from standoff ranges, in

all weathers, using affordable, precision-guided munitions.

The AMSTE program is funded by DARPA and managed by DARPA and

the Air Force Research Laboratory, Rome, N.Y. Development of the

AMSTE demonstration system was led by Northrop Grumman

Integrated Systems Sector, Melbourne Fla., with JDAM weapon subcontract support from Boeing Phantom Works, St Louis Mo., and data

link subcontract support for Raytheon, Tucson, Ariz.

For additional information, please contact Stephen Welby at 

swelby@darpa.mil.

WSTIAC Newsletter 4th Quarter 2002

Robots Powered by the Ocean Itself

They call them "gliders," but these move through water instead of air.

Two new robotic gliders — autonomous underwater vehicles — powered by changes in their own buoyancy or by different temperature layers in the ocean — will be tested operationally in Navy and Marine

Corps exercises off Southern California during 2003. Both gliders were

developed with support from the Office of Naval Research. 

Webb Research of East Falmouth, MA, a company with long experience designing and building oceanographic instruments, will deploy its

Slocum Glider during the exercise. The Slocum Glider uses a Webb

Research heat engine that draws energy from the ocean thermocline

— a layer where the ocean's temperature changes rapidly: it's the

boundary between the warmer water above and the cooler waters

below. The Slocum Glider cycles thousands of times between the surface and a programmed depth, getting the energy it needs to change

its buoyancy from the heat flow of the surrounding water. This longrange deep ocean glider is designed to cruise for five years in a vertical zig-zag from the surface to depths of about 5,000 feet and back.

As it does so it measures salinity and temperature, plots currents and

eddies, counts microscopic plants, and even records "biological"

sounds like whale songs. An earlier battery powered model is used to

study coastal waters up to 656 feet in depth for up to 30 days at a

time. Webb Research named the glider in honor of Captain Joshua

Slocum, who sailed alone around the world in a 37 foot sloop

between 1895 and 1898.

The second robot — the University of Washington Applied Physics

Laboratory's Seaglider — is propelled by buoyancy control and wing

lift to alternately dive and climb along slanting glide paths. It dead

reckons underwater between Global Positioning System (GPS) navigation fixes it obtains at the surface, and so glides through a sequence

of programmed waypoints. It transmits data and receives commands

via satellite data telemetry when it exposes an antenna above the sea

surface for a few minutes between dive cycles. Seaglider has enough

range to cross an entire ocean basin in missions that last months, all

the while diving and rising between the surface and waters as deep as

3500 feet. It can be launched and recovered manually from a small

boat with a crew of two, and so doesn't rely on costly ships for its

deployment. Seaglider collects high resolution profiles of physical,

chemical, and bio-optical properties of the ocean. 

The Office of Naval Research is interested in systems like Seaglider

and the Slocum Glider because they offer the Navy and Marine Corps

potential tools for collecting data about regions of the ocean necessary for mine countermeasures and other tasks important to expeditionary warfare. The Office of Naval Research will sponsor demonstrations of these and other advanced mine countermeasures systems

off the beaches of Camp Pendelton, CA, during 2003. These systems

represent advanced science and technology being developed to

detect, identify, and classify mines in shallow and very shallow waters.

They exploit recent advances in sensors (especially lasers, sonar, and

television-like imaging), robotics (the sensors are installed on a variety

of autonomous underwater vehicles — submarine robots), networking,

and signal processing. Developed by teams of government, industry,

and academic partners, the mine countermeasures technologies offer

the prospect of ultimately reducing or eliminating the need for Sailors

and Marines to enter the dangerous shallow waters just off shore in

order to clear mines in preparation for expeditionary operations.

Office of Naval Research Corporate Communications Office

POC: John Petrik, john_petrik@onr.navy.mil, 703-696-5034 ♦
10

Weaponeering Course 

Instructor: Professor Morris Driels, Naval Postgraduate School

Course Description: 

This 2-1⁄2 day short course is based on a very successful

graduate-level weaponeering course developed by

Professor Driels and taught at the Naval Postgraduate

School, Monterey, CA. The course will provide an

overview of the fundamentals of the weaponeering

process and its application to air-to-surface and surfaceto-surface engagements. The course explains the analytical basis of current weaponeering tools known as the Joint

Munitions Effectiveness Manuals (JMEM's) produced by the

Joint Technical Coordinating Group for Munitions

Effectiveness (JTCG/ME). The JMEM's are used by all

Services to plan offensive missions and allow the planners

to predict the effectiveness of selected weapon systems

against a variety of targets. 

Training at Your Location:

WSTIAC can conduct this course at your location to reduce

your travel time and cost. Please call Mrs. Kelly Hopkins to

discuss.

Fee:

The registration fee for this 2-1⁄2 day course is $950 for U.S.

government personnel and $1150 for government contractors. Contractor teams of 3 or more, registered at the same

time, are charged $950 per person.

Location: Huntsville, Alabama

18-20 February 2003

Notice: WSTIAC reserves the right to cancel and/or change

the course schedule for any reason. In the event of a

schedule change or cancellation, registered participants

will be individually informed.

(Course starts at 0800 Tuesday and ends at noon Thursday)

The short course is divided into three parts. 

Part I covers the basic tools and methods used in 

weaponeering:

iThe weaponeering process

iElementary statistical methods

iWeapon trajectory

iDelivery accuracy of guided and unguided 

munitions

iTarget vulnerability assessment

Part II covers the weaponeering process for air-launched

weapons against ground targets:

iSingle weapons directed against point and 

area targets

iStick deliveries (point and area targets)

iProjectiles (guns and rockets)

iCluster munitions

iWeaponeering for specific targets: bridges,

buildings etc.)

iCollateral damage modeling

About the Instructor: 

Professor Driels is a Professor of Mechanical Engineering at

the U.S. Naval Postgraduate School in Monterey California.

He has worked with the JTCG/ME on a variety of topics in

support of the JMEM's for a number of years. He has taught

a quarter long weaponeering course at NPS for three years

and is preparing a text book on the subject.

Security Classification:

The security classification of this course is SECRET (U.S.

citizens only) to facilitate discussions.

Handout Material:

Each student will receive a comprehensive set of course

notes covering the material presented. 

For additional information, contact: 

Mrs. Kelly Hopkins, Seminar Administrator, 

at (256) 382-4747, or by e-mail khopkins@iitri.org

Part III covers the weaponeering process for ground

engagements:

iIndirect fire systems - artillery and mortars.

iDirect fire systems - infantry and armored vehicles.

iMines - land and sea.
11

Director/Chief Scientist’s Corner

A view from Washington

by Dr. Wes Kitchens

NEED HELP? ...TRY WSTIAC!

Are you looking for an easy-to-use contracting vehicle that will permit you to obtain technical support with assigned tasks

and new initiatives? If your organization is like most today, your staff has been cut back and you are hard pressed to

meet all the demands being placed on you. If so, the DoD Weapon Systems Technology Information Analysis Center

(WSTIAC) is available to help you by providing responsive technical and/or programmatic support that can meet your

needs. WSTIAC can do much more than just collect, analyze and disseminate weapons-related information. WSTIAC

can also conduct analytical or/or experimental technical tasks, conduct trade studies, develop and demonstrate prototype

hardware and provide interdisciplinary technical support on a wide variety of topics related to weapons technology and

systems. The IIT Research Institute and WSTIAC are able to team with other companies and organizations to tailor a support package that will meet your exact needs at a reasonable price. 

The WSTIAC contract provides organizations an easy-to-use contract vehicle that can be used to obtain technical support

for tasks in the areas of conventional and directed energy weapons, ground, air and sea platforms, special operations

and developmental/operational testing, among others. The WSTIAC contract vehicle is a multi-year, task-order-type contract that was competitively awarded, permitting WSTIAC to take on new tasks once the task has been approved by the

government and funded by a sponsor.

The WSTIAC is currently conducting more than two dozen technical tasks for the Office of Secretary of Defense, Defense

Agencies, CINCs and Unified Commands, Program Managers and Service laboratories, among others. Current tasks

range in value from tens of thousands of dollars to more than five million dollars and many of them are incrementally

funded, multi-year efforts. New tasks started in FY03 can have a duration through the end of FY06.

The WSTIAC contracting process is relatively simple. WSTIAC personnel work closely with each potential sponsor to define

what needs to be done, documenting our joint understanding in a Statement of Work that is approved by the sponsor.

WSTIAC then submits the Statement of Work electronically to our Contracting Officer's Technical Representative and representatives from the Defense Technical Information Center for approval. Once the Statement of Work is approved, WSTIAC prepares a Technical Proposal and a Cost Proposal and forwards these documents to the government Contracting

Officer. In parallel, the DoD sponsor submits a Military Interdepartmental Purchase Request (MIPR) to the government

Contracting Officer to fund the new task. After review and approval of the supporting documentation, the Government

Contracting Officer issues a contract modification, authorizing initiation of the new task. New tasks can generally be put

in place in three to four weeks. The process described above applies to a Department of Defense (DoD) customer; similar processes are used for other government agencies and non-governmental customers. The bottom line is that the

WSTIAC contracting process is simple, fast and relatively painless for a potential sponsor.

We would like to illustrate the breadth of funded tasks we have taken on in support of specific sponsors. We are presently conducting a task titled "Weapon Systems Technical Studies and Analyses" for the Director for Weapons Systems, Office

of the Deputy Undersecretary of Defense (Science and Technology). As part of this task we have planned and organized

a number of technical meetings and workshops dealing with topics such as ground vehicle robotics, electric armament

and protection, weapons technologies for defeating chemical and biological agent production and storage facilities, and 

4

WSTIAC Newsletter 4th Quarter 2002
12

most recently, collaborative research and development taking place between the DoD and National Aeronautics and

Space Administration (NASA) in the area of power and in-space electric propulsion. The proceedings from each of these

workshops has been archived by WSTIAC and distributed to participants on compact disks. This task is primarily being

conducted by the IIT Research Institute staff.

WSTIAC is also conducting a task for the Defense Information Systems Agency (DISA) Office of Spectrum Management

and the Defense Advanced Research Projects Agency (DARPA) titled "Spectrum Management Process Improvement

Information Analysis Support." As part this task WSTIAC is providing engineering and information analysis support so as

to establish new spectrum management concepts and approaches to expedite the introduction of emerging technologies

and optimize the DoD position with regard to spectrum access. Spectrum management is critical to the successful development and fielding of new weapons systems and this task is providing technology-enabled strategies for alternative spectrum access approaches that can be used throughout DoD by all Services and Agencies to help realize seamless joint

warfighting capabilities. The task is primarily being conducted by the IITRI Research Institute Spectrum Engineering Group

staff.

WSTIAC is conducting a combined theoretical and experimental effort titled "Improved Significant Chemical Kinetic Input

Parameters for Integrated Munitions Effects Assessment (IMEA) for the Defense Threat Reduction Agency (DTRA) that will

significantly improve the kinetic input parameters used by the kinetic chemistry module of the Multi-Chamber Blowdown

Model through the smart application of kinetic theory backed by experiment. This task will improve the accuracy of DoD

models used to predict weapons lethality and collateral effects during the planning of strikes against threat chemical and

biological agent production and storage facilities. This task is primarily being conducted by the IIT Research Institute and

ENSCO.

WSTIAC is also conducting a series of air and missile defense tasks, as represented by the task titled "Air and Missile

Defense Transformation Analysis and Support," for the U.S. Army Air Defense Artillery Center, 32nd Air and Missile Defense

Command and the Joint Forces Command that provide technical assistance and refinement/development of air and missile defense concepts and system requirements, including analysis, planning, execution and simulation support for exercises such as Roving Sands, Foal Eagle and others. These tasks are primarily being conducted by CAS Incorporated.

WSTIAC recently completed an effort for the Army Program Executive Officer for Tactical Missiles titled "Integrated

Munitions Strategy Analysis." This analysis supported an internal Army Field Artillery Center assessment of current and

projected artillery system effectiveness against a variety of target arrays. The IIT Research Institute-developed GENESIS

model was used to simulate weapon system-to-target pairings. The analyses quantified lethality and collateral damage

of selected systems versus specified target arrays and quantified the effectiveness of the selected systems. Approximately

500 different weapon system-to-target arrays were simulated. The results of these GENESIS simulations played a critical

role in the recent U.S. Army Field Artillery Center Program Objective Memorandum (POM) submission.

"The bottom line is that the WSTIAC contracting process is simple, fast and relatively painless for a

potential sponsor."

The WSTIAC staff looks forward to talking to you about your potential needs. For further information, please contact the

WSTIAC Director/Chief Scientist, Dr. Wes Kitchens at (703) 933-3317 or wkitchens@iitri.org. ♦

The WSTIAC Newsletter is the current awareness publication of the Weapon Systems Technology Information Analysis Center (WSTIAC).

WSTIAC, a Department of Defense (DoD) Information Analysis Center (IAC), is administratively managed by the Defense Information Systems

Agency (DISA), Defense Technical Information Center (DTIC) under the DoD IAC Program. The Contracting Officer's Technical Representative

(COTR) for WSTIAC is Mr. H. Jack Taylor, ODUSD (S&T), Defense Pentagon, Washington, D.C. 20301-3080, (703) 588-7405. IIT Research

Institute operates WSTIAC, which services Government, industry, and academia as a Center of Excellence in Weapon Systems Technology.

WSTIAC Director: Dr. Wes Kitchens Database Inquiries: Vakare Valaitis

703.933.3317, Email: wkitchens@iitri.org 703.933.3362 Email: vvalaitis@iitri.org

Internet: http://iac.dtic.mil/wstiac/

All data and information herein reported are believed to be reliable; however, no warrant, expressed or implied, is to be construed as to the

accuracy or the completeness of the information presented. The views, opinions, and findings contained in this publication are those of the

author(s) and should not be construed as an official Agency position, policy, or decision, unless so designated by other official documentation.
13

Introduction to Sensors and Seekers for Smart Munitions

and Weapons Course

Instructor: Mr Paul Kisatsky, IIT Research Institute

Course Description: 

This 2-1⁄2 day short course provides an introduction to the

most commonly used sensors and seekers employed in

smart munitions and weapons (projectiles, missiles and

wide area mines). It is oriented to managers, engineers,

and scientists who are engaged in smart weapons program development and who desire to obtain a deeper

understanding of the sensors they must deal with, but who

do not need to personally design or analyze them in depth.

An undergraduate technical degree is recommended.

Mathematics is kept to a minimum, but important formulas are introduced. This course also provides an excellent

foundation for those scientists and engineers who desire to

pursue this discipline to intermediate and advanced levels. 

sensors are also briefly discussed. System constraints,

which force tradeoffs in sensor design and in ultimate performance, are also covered. Time permitting, a projection

of future trends in the role of sensors for smart munitions will

be presented, followed by a "brain-storming" session to

solicit student views.

Training at Your Location:

WSTIAC can conduct this course at your location to reduce

your travel time and cost. Please call Mrs. Kelly Hopkins to

discuss.

Fee:

The registration fee for this 2-1⁄2 day course is $950 for U.S.

government personnel and $1150 for government contractors. Contractor teams of 3 or more, registered at the same

time, are charged $950 per person.

Location: Huntsville, Alabama

18-20 March 2003

Notice: WSTIAC reserves the right to cancel and/or change

the course schedule and/or instructor for any reason. In the

event of a schedule change or cancellation, registered participants will be individually informed.

WSTIAC Newsletter 4th Quarter 2002

(Course starts at 0800 Tuesday and ends at noon Thursday)

The course covers:

iClassification of seekers and sensors

iFundamentals of waves and propagation

iFundamentals of noise and clutter

iFundamentals of search footprints

iIntroduction to infrared

iIntroduction to radar

iIntroduction to ladar

iIntroduction to visionics

iIntroduction to acoustics

iFuture projections and interactive brainstorming

Noise and clutter, the predominant obstacles to success in

autonomous seekers, are given emphasis. The major sensor types are classified and each is discussed. In particular, infrared, radar, optical laser radar (ladar), imaging

and non-imaging, and acoustic sensors are individually

covered. Of special interest is the discussion on human

visionics versus machine recognition, since this concept is

of central importance to understanding autonomous versus man-in-the-loop sensing systems. The implications of

"artificial intelligence", "data fusion", and "multi-mode" 

About the Instructor: 

Mr. Paul Kisatsky is a Senior Physical Scientist with the IIT

Research Institute. He is a nationally recognized expert on

sensors and seekers for smart munitions and weapons and

has more than 30 years of hands-on experience developing sensors and seekers fielded in modern smart munitions

and weapons.

Security Classification:

This course is unclassified.

Handout Material:

Each student will receive a comprehensive set of course

notes covering the material presented. 

For additional information, contact: 

Mrs. Kelly Hopkins, Seminar Administrator, 

at (256) 382-4747, or by e-mail khopkins@iitri.org
14

Smart/Precision Weapons Course

Instructors: Dr. Wes Kitchens, Mr. Hunter Chockley and Mr. Mark Scott, 

IIT Research Institute

Course Description: 

This 2-1⁄2 day short course provides a comprehensive

understanding of smart weapons and related technologies. This course is aimed at providing general

knowledge about smart weapons technology and a

source of current information on selected U.S. and foreign smart weapons, to include system description,

concept of employment, performance characteristics,

effectiveness and program status.

A variety of ground, sea and air smart/precision

weapon systems are discussed, to include fielded

and/or developmental U.S. systems such as Joint

Direct Attack Munition (JDAM), Joint Air-to-Surface

Standoff Missile (JASSM), Small Diameter Bomb,

Javelin, Line-of-Sight Anti-Tank (LOSAT), XM982

Excaliber, Extended Range Guided Munition (ERGM),

Common Missile, Tomahawk, Standoff Land Attack

Missile - Expanded Response (SLAM-ER), Cluster

Bomb Munitions and Airborne Laser, among others, as

well as representative foreign smart/precision

weapons.

The objective of this course is to inform materiel and

combat developers, systems analysts, scientists, engineers, managers and business developers about

smart/precision weapons, to include:

Training at Your Location:

WSTIAC can conduct this course at your location to

reduce your travel time and cost. Please call Mrs. Kelly

Hopkins to discuss.

Fee:

The registration fee for this 2-1⁄2 day course is $950 for

U.S. government personnel and $1150 for government

contractors. Contractor teams of 3 or more, registered

at the same time, are charged $950 per person.

Location: Huntsville, Alabama

19-21 November 2002, 4-6 March 2003, 15-17 April 2003, 

17-19 June 2003 and 5-7 August 2003

Notice: WSTIAC reserves the right to cancel and/or

change the course schedule and/or instructor for any

reason. In the event of a schedule change or cancellation, registered participants will be individually

informed.

(Course starts at 0800 Tuesday and ends at noon Thursday)

iState of the art of representative U.S. and 

foreign smart weapons systems;

iEmployment concepts

iSmart weapons related systems, subsystems,

and technologies; and

iTechnology trends.

About the Instructors: 

Dr. Wes Kitchens is the Director of WSTIAC and the former DoD Director for Weapons Technologies. Mr. Mark

Scott and Mr. Hunter Chockley are IITRI Science

Advisors. Each instructor has more than 25 years of

experience with weapons technology and/or smart/precision weapons.

Security Classification:

The information presented is kept at the unclassified

level, but is designated FOR OFFICIAL USE ONLY

(FOUO) and is export controlled. The security classification of this course is SECRET (U.S. citizens only) to facilitate discussions.

Handout Material:

Each student will receive a comprehensive set of course

notes covering the material presented. 

For additional information, contact: 

Mrs. Kelly Hopkins, Seminar Administrator, 

at (256) 382-4747, or by e-mail khopkins@iitri.org
15

NOVEMBER 2002

5-7 November 2002

AIAA Missile Sciences Conference

Montere, CA

For additional information:

http://www.aiaa.org/calendar/ 

19-21 November 2002

Smart/Precision Weapons Course

Huntsville AL

For additional information 

Call Kelly Hopkins 256.382.4747

Email: khopkins@iitri.org

DECEMBER 2002

11-12 December 2002

UAV USA Conference - Unmanned Aerial Vehicles

UAVs in support of the Global War on Terrorism

Washington DC

For additional information

Email: ag@shephard.co.uk

www.uavusa.com 

JANUARY 2003

12-14 January 2003

ACM-SIAM Symposium on Discrete Algorithms

Baltimore MD

For additional information

http://www.siam.org/meetings/calendar.htm 

14-17 January 2003

Fifteenth National Symposium

Surface Navy Association

Arlington VA

For additional information

http://www.navysna.org/2003%20Symposium/index.html 

FEBRUARY 2003

10-13 February 2002

SIAM Conference on Computational Science

and Engineering

San Diego CA 

For additional information

http://www.siam.org/meetings/calendar.htm 

10-13 February 2003

2003 Electronic Components for the 

Commercialization of Military and Space Systems

Los Angeles CA

For additional information

http://www.cti-us.com/ucmsemain.htm 

MARCH 2003

8-15 March 2003

2003 IEEE Aerospace Conference

Big Sky MT

For additional information

http://www.aeroconf.org/ 

4-6 March 2003

Smart/Precision Weapons Course

Huntsville AL

For additional information Call Kelly Hopkins 256.382.4747

Email: khopkins@iitri.org

18-20 March 2003

Weaponeering Course

Huntsville AL

For additional information Call Kelly Hopkins 256.382.4747

Email: khopkins@iitri.org

APRIL 2003

14-16 April 2003

Smart/Precision Weapons Course

Huntsville AL

For additional information Call Kelly Hopkins 256.382.4747

Email: khopkins@iitri.org

MAY 2003

26-28 May 2003

The 10th Saint Petersburg International

Conference on Integrated Navigation Systems

St Petersburg Russia

For additional information

http://www.elektropribor.spb.ru/ 

JUNE 2003

17-19 June 2003

Smart/Precision Weapons Course

Huntsville AL

For additional information Call Kelly Hopkins 256.382.4747

Email: khopkins@iitri.org

AUGUST 2003

5-7 August 2003

Smart/Precision Weapons Course

Huntsville AL

For additional information Call Kelly Hopkins 256.382.4747

Email: khopkins@iitri.org

11-14 August 2003

AIAA Guidance, Navigation, and Control Conference

Austin TX

For additional information

http://www.aiaa.org/calendar/index.hfm?cal=1 

Upcoming Conferences and Courses

WSTIAC Newsletter 4th Quarter 2002
16

Inside this issue

Anti-Jam GPS Part IV

FYI

Director’s Corner

In the news

New Weaponeering Course

Calendar of Events

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