FIVE-CHANNEL DOWNCONVERTER MODULE WITH INPUT RF
SWITCH/LIMITER AND LO AMPLIFIER/DIVIDER
MODEL SERIES: DSS0818
FEATURES
• RF/LO coverage ................ 8 to 18 GHz
• Ideal for broadband DF receivers
• External IF phase/amplitude adjustments
• Channel-to-channel RF tracking
Phase ................................. ±5° typical
Amplitude .......................... ±0.5 dB typical
• Remote band/blanking/BIT selection
MITEQ’s Model DSS Series integrates our standard broadband double-balanced mixer designs with input limiter protection
diodes and IF amplifiers to provide a phase- and amplitude-tracked five-channel downconverter with an integrated LO
amplifier/splitter. A three-way input switch/limiter provides remote band/blanking/BIT select and protection from undesired
high signal levels. This module is most often used as the “front-end” of a direction-finding system using four antennas in
the azimuth, elevation or combined directions and a fifth antenna channel to resolve additional received strong “back or side
lobe” signals and to identify the receiver image response. The DSS0818 is also useful as an instantaneous frequency monitor with suitable input frequency to phase encoders (application notes available).
ELECTRICAL SPECIFICATIONS
INPUT PARAMETERS
RF/LO frequency range
RF power, 1 dB compression
RF power
RF power (maximum peak,
5 µs pulse, 1% duty cycle)
LO power, operating
RF and LO VSWR (RF = -10 dBm, LO = -15 dBm)
BIT (built-in-test) control (3 BITS)
DC current at ±12 V
CUSTOM PRODUCTS
TRANSFER CHARACTERISTICS
Conversion gain (RF input to IF output,
with gain adjustment of ±5 dB)
Conversion gain flatness
Single-sideband noise figure at 25°C
LO-to-RF isolation
LO-to-IF isolation
RF-to-IF isolation
Output two-tone third-order intercept point
Output two-tone second-order intercept point
Channel-to-channel isolation
Channel-to-channel amplitude tracking
Channel-to-channel phase tracking
IF gain adjust
IF phase adjust
CONDITION
UNITS
MIN.
LO1 and LO2
@ 6 dB gain nominal
Maximum average
GHz
dBm
Watts
Watts
8
LO1 and LO2
dBm
Ratio
Logic
mA
-18
-15
1.5:1
TTL
700
-12
CONDITION
UNITS
MIN.
TYP.
MAX.
dB
3
8
13
Across RF band
Including LO amplifier gain
LO = -15 dBm
OUTPUT PARAMETERS
IF frequency range
IF VSWR (IF = -10 dBm, LO = -15 dBm)
475
-3 dB bandwidth
Ratio
±dB
dB
dB
dB
dB
dBm
dBm
dB
dB
Degrees
±dB
±Degrees
TYP.
MAX.
18
-7
2
200
0
1
10
5
50
60
+25
+48
40
±0.5
±5
14
10
±1
±15
5
20
UNITS
MIN.
TYP.
MAX.
MHz
80
2:1
160
240
DSS0818 TYPICAL TEST DATA
VSWR
(LO = +15 dBm)
ISOLATION
0
3.0:1
10
0
20
LO TO RF (dB)
VSWR (RATIO)
LO TO RF
2.5:1
LO
2.0:1
40
20
60
30
CHANNEL TO CHANNEL
80
40
1.5:1
RF
1.0:1
8
10
12
14
FREQUENCY (GHz)
16
18
8
10
14
NOISE FIGURE
12
8
8
CONVERSION GAIN
4
4
AMPLITUDE TRACKING (dB)
CONVERSION LOSS (dB)
18
0
12
14
FREQUENCY (GHz)
16
+10
+5
0
-5
-10
PHASE
+2
+1
0
-1
-2.0
18
AMPLITUDE
8
10
12
14
16
PHASE TRACKING (DEG.)
16
NOISE FIGURE (dB)
16
10
16
PHASE AND AMPLITUDE TRACKING
20
8
14
FREQUENCY (GHz)
CONVERSION GAIN
NOISE FIGURE
12
12
CHANNEL TO CHANNEL (dB)
3.5:1
18
FREQUENCY (GHz)
OUTLINE DRAWING
.330 [8.38]
.640 [16.26]
S/N XXXXXX
CONN, RF
SMA FEMALE
J6 LO1
J9
J12
J10
RF PROCESSOR
3.325
[84.46]
J11
V
B
3.875
[98.43]
D
J18 POWER
RF IN
CHANNELS
T
C
J5
J3
J10
J8
4.375
111.13]
D
J4
J9
.250
[6.35]
.250
[6.35]
2.812 [71.42]
5.625 [142.88]
6.125 [155.58]
D TYPE CONNECTOR (15 PIN)
DC POWER AND CONTROL SIG.
(MATCHING CONNECTOR SUPPLIED)
3.500
[88.90]
.171 [4.34] DIA THRU
(6 HOLES)
IF OUTPUTS:
CONNECTOR: RF
SMA FEMALE
(5 PLACES)
CUSTOM PRODUCTS
.28 [7.11]
M/N SA0502C06B
C
B
J2
J7
BAND 3
(J6; J7; J10; J8; J9)
3.325
84.46]
J7 LO2
A
A
J1
J6
.600 [15.24] (TYP.)
CONNECTOR, RF
SMA FEMALE
(10 PLACES)
PHASE
ADJ
GAIN
ADJ
J8
BAND 2
(J1; J2; J3; J4; J5)
8.50±.125 [215.90]
NOTE: All dimensions shown in brackets [ ] are in millimeters.
476
BLOCK DIAGRAM OF MITEQ 5-CHANNEL GAIN- AND PHASE-MATCHED FRONT END
INPUT
CHANNEL A
MIXER ASSEMBLY
SW/LIM.
J1
BAND 2
J6
BAND 3
PHASE AND GAIN BOARD
DIPLEXER
PHASE ADJ
GAIN ADJ
J13
IF OUT
CHANNEL A
DIPLEXER
PHASE ADJ
GAIN ADJ
J14
IF OUT
CHANNEL B
DIPLEXER
PHASE ADJ
GAIN ADJ
J17
IF OUT
CHANNEL C
DIPLEXER
PHASE ADJ
GAIN ADJ
J15
IF OUT
CHANNEL D
DIPLEXER
PHASE ADJ
GAIN ADJ
J16
IF OUT
CHANNEL V
CHANNEL B
J2
BAND 2
J7
BAND 3
CHANNEL C
J5
BAND 2
J10
BAND 3
CHANNEL D
J3
BAND 2
J6
BAND 3
CHANNEL V
J4
BAND 2
J9
BAND 3
EXTERNAL ADJUST
(TYPICAL 5 PLACES)
EXTERNAL ADJUST
(TYPICAL 5 PLACES)
LO
BIT
INPUT INPUT
CHANNEL
PHASE/AMP.
TRACKING
FREQUENCY
CONVERSION
A
•
RF > LO
B
•
RF > LO
C
•
RF > LO
D
•
RF > LO
T
RF < LO
APPLICATION NOTES
D SIN Ø
LIM
B
Ø
PHASE
DETECTOR
LOCAL
OSC
D
INPUT SIGNAL
CUSTOM PRODUCTS
BLOCK DIAGRAM OF SIMPLE TWO-CHANNEL ANGLE OF ARRIVAL
(A.O.A) MEASUREMENT SYSTEM (REF 1.)
Ø
A
PHASE DIFFERENCES = ψ =
LIM
-2
D
λ
SIN Ø
MITEQ PDL SERIES
1. “Microwave Passive Direction Finding”, S. Lipsky, 1987, John Wiley & Sons publisher TK6565.D5L57.
477
Ø
APPLICATIONS OF FIVE-CHANNEL FRONT ENDS
DIRECTION FINDING APPLICATIONS
L1
L1
REF
2L1
R2
R3
4L1
R4
R5
PHASE-MATCHED FIVE-CHANNEL MIXER,
LIMITER PHASE DETECTOR SET
REF
COURSE RESOLUTION
ANGLE INDICATORS
ALTERNATIVE APPLICATIONS
Can the basic direction-finding receiver also be used to measure incoming frequency?
Yes, by first encoding the received signal into two separate outputs that have a phase difference in
direct proportion to their frequency:
MITEQ IQM SERIES
0°
3 dB
R
K SIN Ø
L
RF
IN
0°
3 dB
LIMITER
90°
3 dB
R
L
VERT.
HORIZ.
K COS Ø
FREQ.TO
PHASE ENCODING,
CABLE LENGTH
A large cable length difference in the two splitter outputs will yield rapidly varying phase with frequency. If these
outputs are applied to a two-channel DF system, the output phase difference, together with knowledge of the
encoder cable lengths, can be used to determine input frequency. This is the basic principle of an instantaneous frequency monitor (IFM). In actual practice, several frequency encoders are used with progressively
greater frequency resolution, similar to how one reads the dials of a gas or an electric meter.
FREQ. TO PHASE ENCODER, CABLE NETWORK
O1
–
O2
–
O3
–
O4
–
O5
–
R2
R3
R4
R5
INSTANTANEOUS
FREQ. MONITOR (IFM)
PHASE-MATCHED FIVE-CHANNEL MIXER,
LIMITER PHASE DETECTOR SET
REF
COURSE RESOLUTION
CUSTOM PRODUCTS
REF
FREQUENCY INDICATORS
478