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Key Features

Latching Circulator

Driver

1. 15,682.523520 MHz2. 94.0951420 GHz

21

Phase Locked Oscillator

1. 9.976160 MHz @ +10 dBm

Tx Mult. = 9438LO Mult. = 9432

2. 59.856960 MHz @ +23 dBm3. 39.904640 MHz @ +10 dBm

4. 119.713920 MHz @ +10 dBm5. 129.690080 MHz @ +10 dBm

1 2

1. 15,692.499680 MHz

2. 94.15499808 MHz

5

41

3

EIA Over TempModulator Faults

EIAAntenna

ThermistorH V

VH

Mixer &Preamp

Noise Diode

IF Freq. 59.856960 MHz

Timing & Control

Phase Locked Oscillator Multiplier

Ultra QuietOscillator Power Supply Faults

Pulse Timing

Transmitter Power

Supply &HV Power

Modulator

NASA GFSC 94 GHz Cloud Radar System

Data Acqusition System

& Digital Receivers

94.155 GHz

−30 dB

Detector

Computer & VME Bus Based

,- . /0 1 23 4 567 8 9 6 :; 5< ;7 = ; 6 8 6 ;> ?@ <A 8 B6 8 6 ; CD E F =G2 ? B C 9> H 6 E 5 = =7 8 =I =@ <J = 8 6 7 8K < L7 < 7 F H = M , C ,N B 4 O H :P H

6 @ F : FA 8 = 2 OQ RG 9 6 :;S ; 6 T F> L H :S H =G A @ 6 F = E 6 E6 F =@ @ : F = I : = L < T

S @ <A 8 6 7 8J ; =S :J : F6 F : < 7 ED E F =G EU ? B C : E 6 TA @ @ D S < H =; =7 F> J < 4@ 6 ; : G = F =; :S V<J J @ =; ; 6 8 6 ; U W F : ES 6J 6 5@ = < T 8 = F =S F :7 P S @ <A 8 E 6 7 8

J ; =S :J : F6 F : < 7 T; < G F H = P ; <A 7 8 EA ; T6 S = F< A J J =; F; <J < EJ H =; = U W F

: E = EJ =S : 6 @ @ D EA : F = 8 T< ; S :; ;A E S @ <A 8 E FA 8 : = E 5 =S 6A E = < T : F E H :P H

E =7 E : F : I : FD 6 7 8X 7 = EJ 6 F : 6 @ ; = E< @A F : < 7 U Y H =A 7 :Z A =S < G 5 :7 6 F : < 7

< T ? B C L : F H < F H =; E =7 E< ; E < 7 5< 6 ; 8 < 7 N B 4 O> 6 E L =@ @ 6 E F H =

:7 E : FA 8 6 F6 T; < G < F H =; 6 :;S ; 6 T F E 6 7 8 S < 4 @ < S 6 F = 8 G =6 EA ; =G =7 F E

T; < G P ; <A 7 8 4 56 E = 8 6 7 8 EJ 6 S = 4 5 < ;7 = :7 E F;A G =7 F EJ ; < I : 8 = EA 7 4

J ; =S = 8 =7 F = 8 <J J < ; FA 7 : FD F< E FA 8 D F H = ; 6 8 : 6 F : < 7 = [ =S F E < TS @ <A 8 E

< 7 F H = P @ < 56 @ =7 =; P D 5A 8 P = F U Y H = 6 7 6 @ D E : E < T ? B C 8 6 F6 L : @ @

6 @ E< : G J ; < I = <A ; R7 < L@ = 8 P = < 7 6 FG < EJ H =; :S ES 6 F F =; :7 P 6 7 8 6 F 4F =7 A 6 F : < 7 6 F- . /0 1 67 8 J ; < I : 8 = E I 6 @A 6 5@ = ; = T =; =7 S = T< ; F H =

: G J @ =G =7 F6 F : < 7 6 7 8 6 @ P < ; : F H G I 6 @ : 8 6 F : < 7 < T F H = < 7 P < :7 P M , C ,

?@ <A 8 C 6 FJ ; < P ; 6 G > L H :S H L : @ @ A E = 6 - . /0 1 EJ 6 S = 4 5< ;7 =S @ <A 8

; 6 8 6 ; T< ; :S =S @ <A 8 8 = F =S F : < 7 < 7 F H = P @ < 56 @ ES 6 @ = U

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Figure 3. CRS system block diagram.

(a) (b)

(d)(c)

Figure 4. CRS reflectivity and Doppler velocity

Figure 5. Comparison with EDOP and CPL

b. NASA Goddard Space Flight Center, Greenbelt MD 20771

( http://rsd.gsfc.nasa.gov/912/crs )

An Airborne 94 GHz Cloud Radar for NASA ER−2

c. Science Systems & Applications, Inc., Greenbelt MD 20771

a. GEST, Univ. of Maryland Baltimore County, Baltimore, MD 21250

Lihua Li (a) Gerry M. Heymsfield (b) Paul E. Racette (b) Ed Zinker (c) Lin Tian (a)

CRS RF/IF

Figure 2. (a) CRS system operated on the ground. (b) Data system install in ER−2 right wing superpod. (c) ER−2 right

wing tail cone with CRS RF/IF subsystem inside. (d) Bottom view of CRS antenna.

Figure 1. CRS sensitivity estimated from calibrated data.

ER−2 tail cone

CRS data system

CRS antenna

CRS RF/IF

ER−2 tail cone