Ampl.

Balance

0 dB

0.25

0.5

0.75

1.0

2.0

IMP-2 Series

IMAGE REJECT MIXERS

10 to 3000 MHz / Image Rejection up to 30 dB / Internal Summing Quadrature / Hi-Rel Package

Forfurtheri

nformati

oncontact

M ERRIM AC /41 Fairfield Pl.,W estCaldw ell,NJ,07006 /973-575-1300 /FAX 973-575-0531

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.

GENERAL SPECIFICATIONS

(when used as a Down Converter)

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.

(For bandwidth as above)

Operating Temp:

-- 55° to +85°C

PRINCIPAL SPECIFICATIONS

Model

LO Center

Bandwidth Outline

MHz

Style

IMP-2S-***/

10 - 1000

S

IMP-2U-***/ 1000 - 3000

U

Model Numbering Note

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

slash number to distinguish it from related units. The format of

23Feb96

IMAGE REJECTION

Phase Error (degrees)

for a given Amplitude and Phase Balance

0

0.5

1

1.5

2

2.5

3

50

45

40

35

30

25

20

15

IMAGE REJECTION

Image

Rejection

Ratio