IMP-2 Series
IMAGE REJECT MIXERS
10 to 3000 MHz / Image Rejection up to 30 dB / Internal Summing Quadrature / Hi-Rel Package
IMAGE REJECTION
IMAGE REJECTION
50
for a given Amplitude and Phase Balance
45
PRINCIPAL SPECIFICATIONS
Model
LO Center Bandwidth Outline
Number Freq., f
o
, MHz
MHz
Style
IMP-2S-***/ 10 - 1000
IMP-2U-***/ 1000 - 3000
10% of f
o
10% of f
o
S
U
Model Numbering Note
40
35
A complete model number shall be assigned upon
establishment of a full performance specification by the factory
in conjunction with the customer. The model number shall
include an indicator of the center frequency (f
0
) and a special
slash number to distinguish it from related units. The format of
model numbers is as above where *** = f
0.
Ampl.
Balance
0 dB
0.25
0.5
Image
Rejection
Ratio
30
GENERAL SPECIFICATIONS
(when used as a Down Converter)
25
0.75
1.0
20
2.0
15
0
0.5
1
1.5
2
2.5
3
Phase Error (degrees)
RF/LO Input Characteristics
Impedance:
50
Ω
nom.
VSWR:
1.5:1 max.
RF Power Level:
0 dBm nom.
LO Power Level:
+10 dBm nom.
IF Bandwidth:
up to an octave
RF Bandwidth:
up to an octave
LO Bandwidth:
10%
Output Characteristics
Conversion Loss:
9 dB max.
Image Rejection:
25 dB min.
Operating Temp:
-- 55° to +85°C
(For bandwidth as above)
General Notes:
1. Image Rejection Mixers are integrated networks composed of an in-phase power divider, two double balanced mixers and two 90°
quadrature hybrids. Their principal function is the separation of two signals closely spaced in the frequency domain in, for example, a
receiver’s IF stage.
2. An
image
is a spurious signal occurring in a receiver’s IF stage together with the
real
signal. Both result from the mixing process.
Normally, a passband filter selects the real signal while rejecting the image. However, when the frequency difference between the real
and image signals is relatively small, conventional bandpass filters are generally inadequate.
3. In an Image Reject Mixer, the image is separated from the real signal by vector subtraction. The resulting attenuation of the image
is usually expressed as the ‘‘Image Rejection Ratio’’ in dB. (See graph).
4. Several factors affect attainable image rejection. For example, image rejection is a function of bandwidth, the phase and amplitude
balances of the individual components chosen, mixer sensitivity and VSWR interaction among other factors. The graph allows estimating
attainable image rejection under the variables of phase error and amplitude imbalance.
5. Merrimac offers a wide range of Image Reject Mixers for numerous applications. All units are designed and built in accord with
applicable specifications. Designers are invited to work closely with Merrimac engineers to insure best results.
6. All Merrimac Image Reject Mixers comply with applicable sections of MIL-M-28837 and may be supplied screened for compliance
with additional specifications for military and space applications requiring the highest reliability.
23Feb96
F rf t e if r to c n a t
M ERRI AC /41 Faifel Pl,W estCal el,NJ,07006 / 973-
o ur h r n o ma in o t c
M
ri d .
dw l
575-
1300 /FAX 973- 0531
575-
MERRIMAC [ MERRIMAC INDUSTRIES, INC. ]
