Microwave Phase Shifter | Digital Phase Shifter

Application Notes for Microwave Phase Shifter

DIGITAL PHASE SHIFTER & ANALOG PHASE SHIFTER

Both Series, 77 and 78, comprise a family of eight solid-state PIN diode phase shifters covering the frequency range from 0.5 to 18 GHz in four bands: 0.5 to 2 GHz, 2 to 6 GHz, 4 to 12 GHz and 6 to 18 GHz. All models provide a full 360° range of phase shift and may also be used for frequency translation applications.

Each unit is an integrated assembly of an RF vector modulator and a driver circuit, consisting of a 10-bit D/A converter and a voltage buffer in the Series 77 digital units (see Fig. 1A) and a voltage converter and buffer in the Series 78 analog configuration (see Fig. 1 B).

The phase in the Series 77 is digitally controlled over a full 360° in 0.35° discrete steps. The voltage converter in the Series 78 consists of a 8 bit A/D converter followed by D/A converter, and converts a continuous analog input voltage into discrete steps of 1.41°.

10 Bit 360 digital phase shifters and frequency translators, Series 77 and 78 pin diode - Kratos General Microwave

5 to 18 GHz in four bands

0.5 to 2 GHz
2 to 6 GHz
4 to 12 GHz
6 to 18 GHz

10 Bit digitally programmable (Series 77)
Analog control (Series 78)
High speed
Guaranteed monotonicity

Series 78 phase shifter/frequency translator block diagram

Series 77 phase shifter/frequency translator block diagram

Phase Shift

Phase shift is achieved utilizing the RF vector modulator approach shown in Fig. 2. The 3 dB hybrid coupler divides the RF signal into two quadrature components which are then modulated in proportion to the sine and cosine of the desired phase shift. The signals are then combined in-phase to yield the phase-shifted output.

RF vector modulator diagram, Series 77 and 78

Frequency Translator (Serrodyning)

Special attention in the design of the units has been paid to those characteristics which affect their performance as frequency translators. These include minimizing PM-to-AM conversion, use of high slew rate drivers, and optimizing phase shift linearity with applied signal. As a result, carrier and sideband suppression levels of over 25 and 20 dB, respectively, are obtained in the main bands. The same carrier and sideband performance can be realized over the full stretch band when the internal frequency correction circuit is employed.

See Fig. 3 for input voltage control requirements for Series 77 and 78 when used as a frequency translator.

On special order, frequency translators can be provided for operation over reduced bandwidths with suppression levels of up to 35 dB. Consult the factory for special requirements

Series 77 and 78 input requirements chart

PERFORMANCE CHARACTERISTICS

SERIES 77

Control

-10 bit TTL

Nominal Resolution

0.35^o

Logic Input

Logic “0” (Bit OFF)

-0.3 to +0.8V @ 500 µA max

Logic “1” (Bit ON)

+2.0 to +5.0V @ 100 µA max

SERIES 78

Control Voltage

0 to +6V

Sensitivity

23.4 mV/LSB

Resolution

1.41°

Step Uncertainty

0.7° max, 0.3°typ.

Input Resistance

2K ohms

COMMON TO BOTH SERIES 77 & 78

Power Handling Capability Without Performance Degradation

+20 dBm (+7 dBm for 7720A, 7820)

Survival

+30 dBm

Harmonics

30 dBc

Phase Variation

0.1°/°C

POWER SUPPLY REQUIREMENTS

VOLTAGE

SERIES 77

SERIES 78

+5V to +5.5V

100 mA

200 mA

+12 to +15V

100 mA

-12 to -15V

90 mA

RECOMMENDED SEQUENCE OF POWERING THE SUPPLIES

Set command lines to logic level “0”.

Turn on the -12 to -15V power supply.

Turn on the +12 to +15V power supply.

Turn on the +5V power supply.

Set command lines to logic level “1”.

Now you can start to work (if you want for example zero phase, set again all control lines to “0”)

PHASE SHIFTER SPECIFICATIONS

MODEL NOS.

FREQUENCY RANGE (GHz)

INSERTION LOSS (Max.)

VSWR (Max.)

ACCURACY(1) (Max.)

PM/AM (Max.)

7720A & 7820

Main Band 0.7-1.9⁽¹⁾

11.5 dB

1.75

±10°

±1.1dB

Stretch Band 0.5-2.0⁽²⁾

13.0 dB

±15°

±2.5dB

Band Edges 0.5-0.7 & 1.9-2.0⁽³⁾

13.0 dB

±10°

±1.1dB

7722A & 7822

Main Band 2.6-5.2⁽¹⁾

10.0 dB

1.6

±10°

±1.1dB

Stretch Band 2.0-6.0⁽²⁾

11.0 dB

±15°

±1.5dB

Band Edges 2.0-2.6 & 5.2-6.0⁽³⁾

11.0 dB

±10°

±1.1dB

7724A & 7824

Main Band 4.5-10.5⁽¹⁾

10.5 dB

1.8

±10°

±1.1dB

Stretch Band 4.0-12.0⁽²⁾

12.0 dB

±15°

±2.0dB

Band Edges 4.0-4.5 & 10.5-12.0⁽³⁾

12.0 dB

±10°

±1.1dB

7728A & 7828

Main Band 8.0-18.0⁽¹⁾

12.0 dB

2.0

±12°

±1.25dB

Stretch Band 6.0-18.0⁽²⁾

±15°

±2.0dB

Band Edges 6.0-8.0⁽³⁾

±12°

±1.25dB

OTHER SPECIFICATIONS

Switching Speed (50% TTL to within 10° of Final Phase Value): 500 ns Max.
Minimum phase shift range: Series 77: 360° in 1024 Steps (10 -bit) Series 78:360° @ 60°/volt

FREQUENCY TRANSLATOR SPECIFICATIONS

TRANSLATION RATE (min.)

CARRIER (1) SUPRESSION (min.)

SIDE BAND (1) SUPRESSION (Min)

INTERATION LOSS VARIATION (Max.) with translation rate:

0 to 50 kHz⁽⁴⁾

Main Band: 25dB
Stretch Band: 18dB

Main Band: 20dB
Stretch Band: 15 dB

50kHz: 1dB

>50 to 500 kHz⁽⁴⁾

Main Band: 20dB
Stretch Band: 15dB

Main Band: 18 dB
Stretch Band: 12 dB

200kHz: 1dB
500kHz: 3dB

NOTES: BAND SELECTION BY PIN 3 OF J3 LOGIC LEVEL ASSIGNMENT

For Main Band optimized operation, apply logic HIGH to pin 3 or leave it floating.
For Stretch Band operation, apply logic HIGH to pin 3 or leave it floating. While performance is optimized over the Main Band, the reduced performance as stated in Stretch Band specifications apply to band edges.
For Band Edges optimized operation, apply logic LOW to pin 3.
All specifications are met using five most significant bits for 0 to 50 kHz translation rates. For 50-500 kHz translation rates, only the four most significant bits are used.

TYPICAL PERFORMANCE
Typical performance charts for Series 77 and 78 phase shifters/frequency translators

NARROW BAND PHASE SHIFTERS

In addition to the standard wide band Phase Shifters, KRATOS General Microwave is offering Narrow Band Phase Shifters. These units are available both as standard catalog units and as customized units meeting specific customer’s requirements. The narrow band units have better performances and lower prices.

Frequency Range

Model Number

Phase Accuracy

PM/AM

Insertion Loss

8.0 to 12.4 GHz

7728-NB-0812

± 8^o (max.)

± 0.75 dB

12.0 dB (max.)

12.0 to 14.5 GHz

7728-NB-1214

± 8^o (max.)

± 0.75 dB

12.0 dB (max.)

ENVIRONMENTAL RATINGS – OPTION G09

Operating Temperature Range

-54° to + 100°C

Non-Operating Temperature Range

-65° to + 125° C

Humidity

MIL-STD-202F, Method 103B, Cond. B (96 hrs at 95%)

Shock

MIL-STD-202F, Method 213B, Cond. B (75 G, 6 msec)

Vibration

MIL-STD-202F, Method 204D, Cond. B (.06″ double amplitude or 15G, whichever is less)

Altitude

MIL-STD-202F, Method 105C Cond. B (50,000 ft.)

Temp. Cycling

MIL-STD-202F, Method 107D Cond. A, 5 cycles

ACCESSORIES FURNISHED

Mating power/control connector

AVAILABLE OPTIONS

Option no.

Description

Two SMA male rf connectors

One SMA male (J2) and one SMA female (J1) rf connector

G09

Guaranteed to meet Environmental Ratings

G12

RoHS Compliant

G18

REACH Compliant

J3 PIN FUNCTIONS

PIN No.

FUNCTION

SERIES 77 (1)

SERIES 78

-12 V to -15 V

+12 V to +15 V

Freq.Correction Circuit Select⁽³⁾ “0” = Band Edge

Freq.Correction Circuit Select “0” = BandEdge

1.4°⁽³⁾

Not Used

5.6°⁽³⁾

Not Used

45.0°⁽³⁾

Not Used

180.0° (MSB)⁽³⁾

Not Used

90.0°⁽³⁾

Not Used

Ground

Ground (Sig)

0.7°⁽³⁾

Ground (Pwr)

22.5°

Not Used

2.8°

Not Used

11.3°

Not Used

0.35° (LSB)

Control Voltage

+5V to +5.5V DC

Unused logic bit must be grounded.
Must not exceed +7VDC See footnote(3) below.
Must not be greater than +0.3VDC above voltage at pin 15.

OUT LINE DRAWING

MODEL

WEIGHT(APPROX)

7720A

4.95 ± .03(125,7)

3.38 ±.03(85,9)

1.02(25,9)

4.75 ±.01(120,7)

3.12 ± .01(79,2)

2.62(66,5)

1.69(42,9)

2.48(62,9)

.73(18,5)

32(8,1)

13 oz.
(369 gm)

7820

1.48 (37,6)

1.18 (30,0)

.78(19,8)

15 oz.
(425 gm)

7722A

3.25 ± .03(82,6)

.84(21.3)

3.05 ± .01(77,5)

3.00 ± .01(76,2)

1.63(41,4)

1.99(50,5)

1.63(41,4)

.66(16,8)

.32(8,1)

9 oz.
(255 gm)

7822

1.25(31,8)

1.07(27,2)

.72(18,3)

10 oz.
(284 gm)

7724A

.84(21.3)

1.83(46,5)

.66(16,8)

.32(8,1)

9 oz.
(255 gm)

7824

1.25(31,8)

1.07(27,2)

.72(18,3)

10 oz.
(284 gm)

7728A

2.50 ± .03(63,5)

3.00 ±.03(76,2)

.88(22,4)

2.30 ±.01(58,4)

2.75 ±0.1(69,9)

1.50(38,1)

1.63(41,4)

1.25(31,8)

.71(18,0)

.39(9,9)

6 oz. (170 gm)

7878

1.19(30,2)

1.02(25,9)

.69(17,6)

8 oz.
(227 gm)

Dimensions are stated in inches (mm). Tolerances,
unless otherwise indicated: .XX ±.02; .XXX ±.008

Series 77 10 Bit Digital Phase Shifters and Series 78 Analog Phase Shifters & Frequency Translators

DIGITAL PHASE SHIFTER & ANALOG PHASE SHIFTER

PERFORMANCE CHARACTERISTICS

RECOMMENDED SEQUENCE OF POWERING THE SUPPLIES

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