8-12
Digital Radio Transmitter Modules
for 21.2 to 23.6␣ GHz
Technical Data
Description
This digital radio transmitter
module is designed for medium
data rate point to point communi-
cation systems operating at
23␣ GHz. This module offers
excellent phase noise perfor-
mance and can be easily phase
locked to a frequency reference.
The transmitter module provides
+20 dBm of output power, ideal
for use in radios using 2 and 4
level FSK modulation. The module
features an ultra low noise silicon
bipolar VCO operating in the S/C
band. A portion of the oscillator
output is coupled off and is
applied to a frequency divider
network.
Features
• Integrated Microwave/
Millimeter-Wave Modules
• Low Phase Noise
• Silicon Bipolar VCO
• Full Band Tuning
• GaAs MMIC Output Stage
• Sample Output for Phase
Locking
• Excellent Tuning Linearity
• 30 dB Attenuator
• Waveguide/SMA RF Output
• Detected Output
DRT1-23XX
Block Diagrams
MMIC
Mute
BPF MMIC
Detector
Signal
Sample
Output
Tuning
Voltage
Modulation Input
Transmitter Module Without Attenuator
RF Out 21.2
to 23.6 GHz
BPF
LO X4
+4
X2AMP AMP
MMIC
Mute
BPF MMIC
Detector
Attenuator
Attenuator
Control
Signal
Sample
Output
Tuning
Voltage
Modulation Input
Transmitter Module With Attenuator
RF Out 21.2
to 23.6 GHz
BPF
LO X4
+4
X2AMP
AMP
MMIC
AMP
The low frequency output (less
than 1 GHz) from the frequency
divider can be easily used to
phase lock the source. The main
oscillator output is applied to a
frequency multiplier network to
produce the desired output
frequency in the 23 GHz range.
The output of this network is
filtered then amplified by a GaAs
MMIC device to produce the
required output power. A detected
sample of the output signal is
provided to facilitate built in test
of key radio components.
Applications
This digital radio module supplies
the transmitter function in radios
operating in the 21.2 to 23.6␣ GHz
band. The source provides close
to 100 mW output power over the
temperature range of -30°C to
+70°C. Included within the
transmitter module is a muting
function to reduce output power
by 50 dB for “hot standby” appli-
cations. An internal voltage
controlled attenuator function is
optional allowing for 30 dB
dynamic range adjustment.
5965-5090E
8-13
DRT1-23XX Absolute Maximum Ratings (T
A
= -30 to +70ºC)
Parameters Units Ratings
DC Circuit Power +10 Volts 11
+5.0 Volts +5.5
-5.0 Volts -4.5
Power Control Volts 5
Tuning Voltage Volts 17
Notes:
1. Operation in excess of any one of
these parameters may result in
permanent damage.
2. A thermal interface medium must
be used between the bottom of the
package and its mating surface to
ensure optimum heat transfer.
Electrical Characteristics
Part Number
DRT1-2321 or DRT1-2322 DRT1-2311 or DRT1-2312
Parameters
Units Min. Typ. Max. Min. Typ. Max.
RF Tuning Range GHz 21.2 23.6 21.2 23.6
Operating Temperature Range °C -30 70 -30 70
Storage Temperature Range °C -45 85 -45 85
RF Power Output dBm 19 20 19 20
Sample Out Frequency MHz 663 738 663 738
Sample Out Power dBm -10 0 -10 0
Detected Out V 0.4 2 0.4 2
Harmonics and Sub-Harmonics dBc -30 -30
from 2.65 to 55 GHz from carrier [1]
Spurious Output
from 2.65 - 55 GHz [1] dBc -30 -30
@ fo ± 1.0 GHz dBc -50 -50
@ fo ± sample out frequency dBc -40 -40
Phase Noise @ 100 KHz dBc -85 -82 -85 -82
Tuning Voltage V 1 16 1 16
Input Capacitance, Nom pf 27 27
Main Tuning Sensitivity MHz/V 260 335 260 335
Main Tuning Sensitivity Variation 1.5:1 2.0:1 1.5:1 2.0:1
Modulation Bandwidth MHz 20 20
Modulation Sensitivity MHz/V 7 25 7 25
Modulation Sensitivity Variation 1.15:1 1.15:1
over any 300 MHz
DC Circuit Power +10 Volts mA 175 175
+5 Volts mA 975 600
-5 Volts mA 50 50
Frequency Pushing on +10V Line MHz/V 40 50 40 50
based on ±0.2V variation
Return Loss @ Full Power Output [2] d B 10 10
Mute Control dBc -50 -50
Mute Control Range V 0 5 0 5
RF Connector WR 42 or Coax WR 42 or Coax
Attenuator Range dB 30 NA
Attenuator Control Voltage V 0 5 NA
RF Output Dynamic Range
30 Min.
NA
Humidity Non Condensing % 85 85
Condensing % 95 95
Case Size inches
3.50 x 1.25 x 0.40 3.50 x 1.25 x 0.40
Notes:
1. Tested only to 50 GHz
2. Module is unconditionally stable with this load VSWR of 2.0:1
8-14
DRT1-23XX Typical Performance
Powering Up Instructions
The -5 volts must be applied to the
receiver module before applying
the +5 volts. Likewise when
shutting down the receiver
module the +5␣ volts must be
removed before the -5 volts is
Mounting Instructions
Case must be mounted firmly,
with screws, to an adequate
metallic structure that has suffi-
cient thermal properties to
maintain the module case at a
temperature not to exceed 70°C.
Product Options
Specify part number followed by option. For example:
DR T 1 – 23 X X
Model Number Prefix = Digital Radio
T = Transmitter Module
Internal Use
1 = SMA Connector
2 = WR-42 Waveguide Connector
1 = No Attenuator
2 = Attenuator Option
23 = 21.2 to 23.6 GHz Frequency Band
Figure 1. Power Out vs. Frequency.
1 10 100 1000
KHz Offset from Carrier
Figure 4. Phase Noise at 23 GHz vs.
KHz Offset from Carrier.
-140
-100
-120
-40
-80
-60
dBc
(Hz)
2 4 6 8 10 12 14 16
TUNING VOLTAGE (V)
Figure 2. Tuning Voltage vs. Frequency
and Modulation Sensitivity.
200
150
250
100
300
FREQUENCY
(GHz)
MAIN TUNING (MHz/V)
FREQUENCY (GHz)
P
OUT
(dBm)
21
22
24
23
Figure 3. Dynamic Range Adjust.
ATTENUATION
(dB)
ATTENUATOR VOLTAGE
-40
-30
-20
-10
0
023415
15
17
19
23
21
25
21 22 23 24
T = +25°C
T = –30°C
T = +70°C
Spec Min
TUNING VOLTAGE
MODULATION
SENSITIVITY
turned off. The +10␣ volts can be
turned on in any sequence. Failure
to follow this procedure could
cause permanent damage to the
module.
8-15
Case Dimensions
1.25
12x .20
3.50
.65 10x .100
1.89
2.70 .700
.120
12x .22
12x Ø .025
.40 REF
.670
.170
.500
.250
.420
.335 .375
DETAIL A
SEE DETAIL A
2.430
6x Ø
.125
.120 THRU
.445 .500
.500
.445
GND
GND
+5V PA
MOD
ATTEN
TUNE
+5V DIV
GND
DET
DRTI-23XX
S/N XXXX
+10V
DIV OUT
–5V
H
.40 MAX
