SHF Communication Technologies AG
Wilhelm-von-Siemens-Str. 23D • 12277 Berlin • Germany
Phone ++49 30 / 772 05 10 • Fax ++49 30 / 753 10 78
E-Mail: sales@shf.de • Web: http://www.shf.deDatasheet
SHF 46215 B
Optical DP-QAM Transmitter

SHF reserves the right to change specifications and design without notice – SHF 46215 B V003 – Dec. 18, 2012

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Description
The SHF 46215 B is an optical transmitter unit featuring QAM modulation format in two orthogonal
Polarization planes, (DP-QAM). It is a field replaceable plug-in module which needs to be installed in amainframe type SHF 10001 A/B or SHF 10000 A/B/C. Together with other plug-in modules from this
instruments series, a modular and scalable measurement system can be put together.
In a QAM (Quadrature Amplitude Modulation) transmission system, the data is transmitted in the opticalphase and amplitude change between the symbols. Since one transmitted symbol includes theinformation of n bits the symbol rate is reduced by the factor 1/n. Therefore one advantage of a QAM
transmission system is a high spectral efficiency.
In a DP-QAM transmission system the capacity is doubled by transmitting the data in two orthogonal
polarization planes.
The SHF 46215 B uses two modulators (one modulator per polarization plane) integrated in parallel, andconverting four electrical data streams (I and Q in X- and Y-polarization) of up to 32 GSymbols/s into 1
optical data stream of up to 32 GSymbols/s, and hence a total capacity of up to 256 Gbps. The output
optical data in the two orthogonal polarization planes are bit-synchronized in time.
If the input data streams consist of binary signals, the optical output format will be DQPSK. Multilevel
input data streams will generate the PAM/QAM modulation.
The 4 data channels can be switched On and Off independently, thus permitting to generate either PAM
or QAM signals in single- or dual polarisation mode.
The DC biases of the MZ modulators are controlled automatically as other SHF optical transmitter
instruments, to ensure stability for long term measurements.
An optical pulse carver is available as an option.

Features

4 x 32 GSymbols/s optical data streamsAll modulators’ bias conditions controlled automatically

Selectable automatic and manual bias control (ABC circuit)

All features are computer controlled via Bert Control Center softwareLinear operation for QAM

Compressed operation for QPSK (4-QAM)

Options
Option add RZ
Additional pulse carver for RZ (return to zero) or CS-RZ operation

SHF reserves the right to change specifications and design without notice – SHF 46215 B V003 – Dec. 18, 2012

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Functional block diagramuC Control

DP-QPSK Data modulator
MZ
MZ
MZ

90°
Pol.rot.

MZ
Data drivers

CW Light in

IX QX IY QY
Data inModulated
Light outSpecifications – SHF 46215 BParameter

UnitMin.

Typ.

Max.

Comment

Optical parameters
Wavelength range

C- and L-bandconnector to connector,
maximum transmission
without modulation,
without option add RZ

Insertion loss
(for each polarization)dB

DC Extinction ratiodB

20

Return lossdB

30

without optical connector

GHz23-3dB opticalGSym/s

520

14

16

Electrical and electro-optical parameters
Electro-optical bandwidth ofData modulator
Symbol rate
DP-QPSKRZ/ CS-RZ DP-QPSK
Drive amplifier electrical return loss
Data
Data input level
QAM (linear operation)
QPSK (binary signals, limiting)Clock input level (for RZgeneration)
Dynamic signal to noise ratio
DPSK-mode,
either Data IX, QX, IY or QY

3333dB-10

Vpp
Vpp

0.4

0.25
0.9

0.5

1.2

911

measured withSHF 47215
DPSK-receiver.
@ 28 Gbps

SHF reserves the right to change specifications and design without notice – SHF 46215 B V003 – Dec. 18, 2012

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Absolute maximum ratings
Parameter

Unit

Min.

Typ.

Max.

Conditions

Optical input power

dBm

1718

with option add RZ
w/o option add RZ

data amplifier input powerdBm

4

NRZ dataRZ clock driver input power

dBm4CW

General specifications
ParameterMin.

Typ.

Weightkg

3.3

Dimensions

mm

59x213x450

Power consumption

W

20.5

Operating temperature°C

Electrical data input connectors
Optical connectors

1Unit

10Max.

Conditions
w/o Front panel Connectors

35female K (2.92mm)
FC/PC

1

Other connectors available on request.

SHF reserves the right to change specifications and design without notice – SHF 46215 B V003 – Dec. 18, 2012

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Direct Detection Performance Results
The following equipment was used in obtaining these results:
31
SHF 12103 A Pattern Generator at 28 Gbps, PRBS 2 -1
SHF 1550DFB Laser source set to 15mW output power @ 1550 nm.
AMPAQ EDFA + band pass filter.
Agilent 86100A DCA with 70GHz plug-in and precision time base module.
D(Q)PSK signals detected with SHF 47215 28 GBit/s DPSK receiver.
Only IX channel On(DPSK in X-pol)

Only IY channel On(DPSK in Y-pol)

Only QX channel On(DPSK in X-pol)

Only QY channel On(DPSK in Y-pol)

S/N: 13

S/N: 14

S/N: 14

S/N: 15DP-DPSK 56 GBit/s
DPSK in X-pol decoded

DP-DPSK 56 GBit/s
DPSK in Y-pol decoded

S/N: 11

S/N: 13

DP-QPSK 112 GBit/s
QPSK (I-channel) in X-pol decoded

DP-QPSK 112 GBit/s
QPSK (I-channel) in Y-pol decoded

S/N: 10

S/N: 11

SHF reserves the right to change specifications and design without notice – SHF 46215 B V003 – Dec. 18, 2012

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Coherent Detection Characteristics
Figure below shows the single polarization feature of the transmitter output signal captured by using acommercial high speed coherent constellation analyzer and the corresponding time domaincharacteristics of the signal. A narrow line width laser source was used at the input.

Dual polarization DQPSK:The four 28 GBit/s input data channels were provided by using the SHF 12103 A Quad-32 bit patterngenerator

Single polarization QAM:
The two 28 GBaud input data channels were provided by using 2x SHF 611 A DACs to generate the 4level signals and the SHF 12103 A Quad-32 bit pattern generator to drive the DACs.

SHF reserves the right to change specifications and design without notice – SHF 46215 B V003 – Dec. 18, 2012

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