SHF Communication Technologies AG,
Wilhelm-von-Siemens-Str. 23 D • 12277 Berlin–Marienfelde • Germany
Phone ++49 30 / 772 05 10 • Fax ++49 30 / 753 10 78
E-Mail: mail@shf.de • Web: http://www.shf.dePreliminary
Datasheet
SHF 46213A
Optical DQPSK TransmitterSHF 46213A – V004 – 9/Oct/2007

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SHF reserves the right to change specifications and design without noticeDescription
The SHF 46213A is an optical DQPSK transmitter unit. It is a field replaceable plug-in module
which needs to be installed in a mainframe type SHF 10001A or SHF 10000A. Together with otherplug-in modules from this instruments series, a modular and scalable measurement system canbe put together.
In a DQPSK (Differential Quadrature Phase Shift Keying) transmission system, the data istransmitted in the differential optical phase change between the symbols. The data is encoded infour different phase states. Since one transmitted symbol includes the information of two bits thesymbol rate is reduced by the factor ½. Therefore one advantage of a DQPSK transmission
system is a high spectral efficiency.
The SHF 46213A is a parallel modulator which converts 2 electrical data streams (I and Q) of up
to 22 Gbps into 1 optical data stream of up to 22 GSymbols/s. Both electrical data streams
modulate the light by a thermally stable Chirp-free Lithium Niobate Mach-Zehnder modulator witha phase difference of π/2. Before superposition of the two light streams the Q part gets π/2 shiftedin order to have four different phase states in the transmitted signal.

The 2 data channels can be switched On and Off independently, thus permitting to generate either
DPSK or DQPSK signals.
To detect and to demodulate either the I or the Q channel, our new 20 Gbps DPSK opticalreceiver SHF 47211A is the ideal instrument. It is possible to switch between the I and the Q
channel for eye analysis or BER measurement of both channels separately.
For a 40 Gbps BER measurement the SHF 12100B Bit Pattern Generator provides the I and Q
data streams as sub channel option
For the RZ modes, an amplifier amplifies a clock signal which is used to drive a third modulator.
The output from this modulator is a train of pulses of constant width. For the NRZ-D(Q)PSK
modes, the third modulator is biased to allow light through continuously.
The temperature stable modulators and an automatic bias circuit for the data channels ensurehigh stability of the output signal.

Features•

40 Gbps (20 GSymbol/s) optical data streams•

Separate analysis of I and Q channel possible•

Quick optimization of optical eye diagram performance by user adjustable modulator bias
control•

All features computer controlled•

Data modulators’ bias conditions controlled automatically•

Selectable automatic and manual bias control (ABC circuit)

SHF 46213A – V004 – 9/Oct/2007

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SHF reserves the right to change specifications and design without noticeFunctional block diagramuC Control

Data modulator

Pulse modulator

ϕMZ

MZ
MZ
Data drivers

Pulse driver
Delayline

CW Light inModulated
Light out

Clock inA
B
Data inSpecifications – SHF 46213A
Parameter

Unit

Min.

Typ.

Max.

Comment

Optical parameters
Wavelength range

C- and L-band

Insertion lossdB

11

DC Extinction ratiodB

20

Return loss

dB30

13

connector to connector,maximum transmission
without modulation

without optical connector

Electrical and electro-optical parametersElectro-optical bandwidth ofData modulator

GHzSymbol rate
RZ-DQPSKDQPSKDrive amplifier electrical return loss
Data
Clock pulse RZ
Drive amplifier input level
Data input
RZ clock input
Dynamic signal to noise ratio
DPSK-mode, either Data A or B

Gsym/sSHF 46213A – V004 – 9/Oct/2007-3dB electrical

151852222dB-10-10Vpp
0.26
0.5
120.4
1.2
15

measured withSHF 47211
DPSK-receiver.
@ 20Gbps
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SHF reserves the right to change specifications and design without noticeAbsolute maximum ratings
ParameterUnit

Min.

Typ.

Max.

Conditions

Optical input power

dBm

16

NRZ data amplifier input powerdBm

4

NRZ data

RZ clock driver input powerdBm

4

CW

General specifications
Parameter

Unit

Min.

Typ.

Weightkg

3.3

Dimensions

mm

59x213x450

Power consumption

W

20.5

Operating temperature°C

10Conditions
w/o Frontpanel Connectors

35

Electrical data input connectors

K (2.9mm)

Clock input connector

K (2.9mm)

Optical connectors

FC/PC

SHF 46213A – V004 – 9/Oct/2007

Max.

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SHF reserves the right to change specifications and design without noticeTest Measurements
The following equipment was used in obtaining these results:
SHF12100 A Pattern Generator at 21.4 Gbps, PRBS 231-1
SHF 1550DFB Laser source set to 15mW output power @ 1550 nm.
AMPAQ EDFA + bandpass filter
Agilent 86100A DCA with 70GHz plugin and precision timebase module
D(Q)PSK signals detected with SHF 47211 21.4 GBit/s DPSK receiver
only Data A switched ON

only Data B switched ON

S/N: 16

S/N: 16

Both Data A and Data B channel switched ON(DQPSK), 21.4 GSymbols/s:

S/N: 12RZ-DQPSK

CSRZ-DQPSKS/N: 16

S/N: 16

SHF 46213A – V004 – 9/Oct/2007

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SHF reserves the right to change specifications and design without notice