X cut LN SSB-SC Modulator/X cut LN FSK Modulator

Specifications

Model		T·SBX1.5-10-Y-Z	T·FSX1.5-10-Y-Z*1
Modulation speed		10Gbit/s
Operating wavelength		1.55µm
Insertion loss @DC		</=7dB
Optical bandwidth *2		>/=10GHz(RFA,RFB)	>/=10GHz(RFA,RFB,RFC)
Drive voltage (Vπ) @DC		PortA</=3.5V,PortB</=3.5V, PortC</=7.0V	PortA</=5.5V,PortB</=5.5V, PortC</=5.5V
Carrier supression ratio 1st order/0th		>/=20dB	-
Maximum optical input power		10mW
Electrode impedance		Approx.50Ω
Input RF connector		K connector
Optical fiber	Input	0.9mmΦPMF
	Output	0.9mmΦ PMF or SMF
Input/output fiber lead length		>/=0.7m(Input & Output)
Operating temperature		10~40ºC

*1: PATENT LICENSED:PUBLICATION JP2005-134897 *2: 3dB down bandwidth referenced at 130MHz in each sub-MZ

Package size

Ordering Information

*1: If "O"(others) is selected for output fiber or optical connector, please specify. *2: Polarization state of input/output PMFs is slow axis aligned

Recommended configuration

* This recommended configuration is only for giving general ideas of SSB and FSK modulation schemes. Please refer to the operation manual which is included with the product when you use the product. The operation manual shows you the appropriate way to use with any note. (1) For proper adjustment, make optical connection prior to electrical connection otherwise the product may get damage. The optical connection between the product and a power meter, or between the product and a laser source should be made when laser source is off.

Any risk of making connection while laser source is working, such as loss of eyesight, should be at the user.

(2)	The input fiber of the modulator must be optically adjusted with an optical laser source. The schematic diagram is illustrated below.
(3)	The output fiber of the modulator must be optically adjusted with a power meter. The schematic diagram is illustrated below.
(4)	You can work the laser source.
(5)	Adjust the input side connector appropriately so that the input light power to the module is maximized. The internal polarizer will get damage by improper adjustment and cause unexpected optical loss.
(6)	Connections are made as per the schematic diagram illustrated below.

Example of connections (SSB modulator)

* No terminator is required. This product is internally terminated.

How the SSB (Single Side Band) Modulator works

SSB Modulator has optical Ti-diffused wave-guide paths which form nested Mach-Zender structure. Each of the two primary arms contains sub MZ structures. Two RF ports are for modulation and three DC ports are for bias the two sub MZ and one primary MZ. The modulator consists of LiNbO3 crystal which is X-Cut Y-propagation, where you can produce a SSB Modulation just by driving each MZ. (See Fig.1)

e.g. How to produce a SSB Modulation (or Frequency Shifter). 1) DC Supply DC is supplied from DCA to produce the π phase shift between 1st & 2nd arm. DC is also supplied from DCB to produce the phase shift between 3nd & 4th arm. DC is supplied from DCC to get the 1/2π phase shift between MZA & NZB. 2) RF Supply Φ1(t)=ΦcosΩt is entered from RFA, and Φ2(t)=ΦsinΩt it is entered from RFB by using the wide band 90degrees Phase Shifter. * Φ: Modulation Level, Ω : Angular Frequency Fig2 shows the spectrum on each frequency at each point. How the FSK Modulator works Data is input at DCc port in SSB modulator. Phase difference between (5) and (6) is set to be π and RF power having main MZ Vπ amplitude is input. Each component of angular frequency ω+Ω and ω-Ω is produced at data rate in a manner of FSK modulation.

Recommended Configuration for FSK

* No terminator is required. This product is internally terminated.

Recommended Configuration for PSK

* No terminator is required. This product is internally terminated.

General Idea of Opearation 1, D(B)PSK electrical signals are input from RF1,2. 2, Bias points of each sub MZ are set either at the top or bottom of the transfer curve. 3, DC3 is tuned by 90 degrees of phase shift between two signals. 4, Both RF1, RF2 are drived by 2Vpai.

Data Sheet