WO2010016200A1 - Method for evaluating differential transimpedance amplifier, method for evaluating optical receiving circuit, storage media in which programs therefor are respectively stored, and devices - Google Patents

Abstract

Provided is an evaluation method for evaluating the characteristic of a differential transimpedance amplifier with high precision.  Four terminals of a differential transimpedance amplifier (100) are respectively connected to four ports of a 4-port vector network analyzer (101).  The S-parameter of the differential transimpedance amplifier (100) is measured by the 4-port vector network analyzer (101).  The differential-mode S-parameter SDD is calculated on the basis of the measured S-parameter.  The differential-mode Z-parameter ZDD is calculated by using the calculated differential-mode S-parameter SDD.  The transimpedance characteristic ZT of the differential transimpedance amplifier (100) is calculated by using the calculated differential-mode Z-parameter ZDD.

Description

Evaluation method for differential transimpedance amplifier, optical receiver circuit evaluation method, storage medium storing the program, and apparatus

The present invention relates to a differential transimpedance amplifier evaluation method, an optical receiver circuit evaluation method, a storage medium storing a differential transimpedance amplifier evaluation program, a storage medium storing an optical receiver circuit evaluation program, and a differential The present invention relates to an evaluation apparatus for an optical transimpedance amplifier and an optical reception circuit evaluation apparatus.

In a long-distance optical transmission system, an optical receiver circuit that demodulates and amplifies an optical signal is used.
As an example, FIG. 8 shows an optical receiving circuit 200 when differential phase shift keying (DPSK) is used as a modulation code. In FIG. 8, a 1-bit delay interferometer 108 includes a 1-bit delay element 105 in one of a pair of waveguides, and a pair of optical signals S ₁ and S ₂ corresponding to the phase difference between adjacent bits. Is output. The pair of optical signals S ₁ and S ₂ are incident on the two photodiodes 104 and 104, respectively.
The photodiodes 104 and 104 perform photoelectric conversion according to the intensity of each optical signal and output a current signal. The two photodiodes 104 and 104 are directly connected to the differential transimpedance amplifier 100, and the differential transimpedance amplifier 100 amplifies the difference between the signals and outputs the amplified signal. As a result, the DPSK signal is demodulated, amplified and output.

Thus, in the optical receiving circuit 200 that demodulates the DPSK signal, the differential transimpedance amplifier 100 that converts the current signal from the photodiodes 104 and 104 into a voltage signal and amplifies it is necessary.
When further speeding up and capacity increase of information transmission are required, it is important to accurately evaluate the characteristics of the differential transimpedance 100.

Here, as a method of evaluating the gain band characteristic of the differential amplifier, it is common to use a vector network analyzer (VNA) and measure the S parameter to obtain the gain band characteristic (Patent Documents 1 and 2). ).
Vector network analyzers include a two-port type and a four-port type.
Here, FIG. 9 shows a block diagram of a measurement system of the differential amplifier 109 using the four-port vector network analyzer 101. The first terminal and the second terminal, which are input terminals of the differential amplifier 109, are connected to the first port and the second port of the 4-port vector network analyzer 101, respectively, and the first terminal which is the output terminal of the differential amplifier 109. The third terminal and the fourth terminal are connected to the third port and the fourth port of the 4-port vector network analyzer 101, respectively.
FIG. 10 shows a block diagram of a measurement system of the differential amplifier 109 using the two-port vector network analyzer 201. The first terminal on the input side of the differential amplifier 109 is connected to the first port of the 2-port vector network analyzer 201, and the third terminal on the output side of the differential amplifier 109 is the second port of the 2-port vector network analyzer 201. Connect to. The second terminal on the input side and the fourth terminal on the output side of the differential amplifier 109 are connected to a 50Ω termination resistor R ₃ .
FIG. 11 is a diagram showing the results of measurement by the measurement system. In FIG. 11, S _DD31 is a differential mode S parameter obtained from the S parameter measured by the 4-port vector network analyzer 101 of FIG. 9, and S ₂₁ is obtained by the 2-port vector network analyzer 201 of FIG. It is the measured S parameter.
As shown in FIG. 11, when the gain band characteristic of the differential amplifier 109 is evaluated using the S parameter, the 2-port vector network analyzer 201 and the 4-port vector network analyzer 101 can be measured in the same manner. Therefore, S-parameter evaluation data that has the same behavior over a wide frequency range can be obtained. In FIG. 11, a single-phase input is used for the S parameter S ₂₁ of the measured value by the 2-port vector network analyzer 201 and the S parameter S _DD31 of the differential mode obtained from the measured value by the 4-port vector network analyzer 101. Although the difference of 6 dB, which is the difference from the two-phase input, can occur, only the difference of 6 dB is large and the behavior as the frequency characteristic of the gain is widely matched. Band characteristics can be obtained.

However, in a differential transimpedance amplifier, it is necessary to evaluate circuit characteristics using transimpedance characteristics, but a vector network analyzer (VNA) cannot directly measure transimpedance characteristics.
In the low frequency range, the transimpedance Z can also be obtained from the ratio of input current value and output voltage value (V = ZI). Not applicable at all.

JP 2005-055438 A Japanese Unexamined Patent Publication No. 06-088844

An object of the present invention is to provide a differential transimpedance amplifier evaluation method, an optical receiver circuit evaluation method, and a storage medium and apparatus storing the program for evaluating the characteristics of the differential transimpedance amplifier with high accuracy. It is in.

An evaluation method for a differential transimpedance amplifier according to the present invention is an evaluation method for evaluating a relationship between a band of a differential transimpedance amplifier to be evaluated and a transimpedance gain. A measuring step in which terminals are connected to four ports of a four-port vector network analyzer, and the S-parameters of the differential transimpedance amplifier are measured by the four-port vector network analyzer; and the S parameters measured in the measuring step differential mode by using the differential mode S-parameter calculating step of calculating an S parameter S _DD of the differential mode, the S parameter S _DD differential mode calculated by said differential-mode S-parameter calculating step on the basis of the differential mode Z parameter calculation which calculates the Z parameter Z _DD Degree and the differential mode Z parameter transimpedance characteristic Z _T calculating step of calculating a trans-impedance characteristics Z _T of the differential transimpedance amplifier with a Z parameter Z _DD differential mode calculated at calculation step And.

The optical receiver circuit evaluation method of the present invention is an optical receiver circuit evaluation method for evaluating the characteristics of an optical receiver circuit in which photoelectric conversion elements are respectively connected to two terminals on the input side of a differential transimpedance amplifier, Subsequent to the evaluation method of the differential transimpedance amplifier, a transimpedance characteristic Z _T ^* calculation step of the optical receiving circuit for calculating the transimpedance characteristic Z _T ^* of the optical receiving circuit is provided, and the transimpedance characteristic Z of the optical receiving circuit is provided. _{The T} ^* calculation step calculates the impedance characteristic Z _T ^* of the optical receiving circuit by multiplying the impedance characteristic Z _PD of the photoelectric conversion element by the trans impedance characteristic Z _T of the differential transimpedance amplifier. To do.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a differential transimpedance amplifier evaluation method, an optical receiver circuit evaluation method, and a storage medium and apparatus storing the program for evaluating the characteristics of the differential transimpedance amplifier with high accuracy. .

1 is a diagram illustrating an evaluation device for a differential transimpedance amplifier in a first embodiment. FIG. 5 is a flowchart showing an operation procedure of a differential transimpedance amplifier evaluation method in the first embodiment. It is a diagram showing a trans-impedance characteristics Z _T obtained using the evaluation method according to the first embodiment in the graph. 6 is a flowchart showing an operation procedure of an evaluation method in the second embodiment. It is a graph showing a trans-impedance characteristics Z _T ^* of the receiving circuit. In a comparative example, it is a figure which shows the structure of the measurement system which uses 2 port vector network analyzer. In Comparative Example illustrates a transimpedance was determined using the two-port vector network analyzer characteristics Z _T (2-port measurement), and Z _T (simulation) as determined by circuit analysis, the. In description of background art, it is a figure which shows the optical receiver circuit at the time of using differential phase shift keying for a modulation code. In the background art, it is a block diagram of a measurement system of a differential amplifier using a 4-port vector network analyzer. In the background art, it is a block diagram of a measurement system of a differential amplifier using a 2-port vector network analyzer. FIG. 11 is a diagram showing gain band characteristics of a differential amplifier obtained by the measurement system of FIGS. 9 and 10 in the background art.

Embodiments of the present invention will be described below in detail with reference to the drawings.
(First embodiment)
A first embodiment of the present invention will be described.
FIG. 1 is a diagram showing an evaluation apparatus 300 for the differential transimpedance amplifier 100. As shown in FIG.
The evaluation apparatus 300 includes a vector network analyzer (VNA) 101, an arithmetic control unit 110, and a display unit 112 as output means.

The differential transimpedance amplifier 100 to be evaluated has a configuration in which feedback resistors R ₁ and R ₂ are connected to a differential amplifier having two pairs of input / output terminals.
Here, as shown in FIG. 1, the input side terminals are the first terminal and the second terminal, and the output side terminals are the third terminal and the fourth terminal. The feedback resistor R ₁ is provided between the first terminal and the third terminal, the feedback resistor R ₂ is provided between the second terminal and the fourth terminal.

A vector network analyzer (VNA) 101 is a measuring instrument that measures high-frequency characteristics of a circuit and obtains S parameters.
In this embodiment, the vector network analyzer 101 is a 4-port system, and has a first port, a second port, a third port, and a fourth port. The first terminal of the differential transimpedance amplifier 100 is connected to the first port, the second terminal is connected to the second port, the third terminal is connected to the third port, and the fourth terminal is the fourth port. Connect to.

The arithmetic control unit 110 controls the vector network analyzer 101 to acquire the S parameter of the differential transimpedance amplifier 100 and calculates the transimpedance characteristic Z _T of the differential transimpedance amplifier 100 based on the S parameter. .
The arithmetic control unit 110 is a microcontroller including a CPU and a memory, and realizes a function for obtaining the transimpedance characteristic Z _T of the differential transimpedance amplifier 100 by executing an evaluation program stored in the memory. is there. Specific operations will be described later with reference to a flowchart (FIG. 2).
The display unit 112 displays the transimpedance characteristic Z _T calculated by the arithmetic and control unit 110. The output means is not limited to display means such as a display, but may be a printer.
The input unit 102 is a means for operating the arithmetic control unit 110 and the like, for example, setting and changing various parameter values.

Next, an evaluation method of the differential transimpedance amplifier 100 will be described.
FIG. 2 is a flowchart showing an operation procedure of the evaluation method of the differential transimpedance amplifier 100.
This evaluation method is realized by executing the evaluation program of the arithmetic control unit 110.
This evaluation method includes a measurement process (ST100), a calculation process (ST200), and an output process (ST400).
Each step will be described in order.

First, in the measurement step (ST100), the vector network analyzer 101 measures the S parameter of the differential transimpedance amplifier 100.
That is, as shown in FIG. 1, two input side terminals (first terminal and second terminal) of the differential transimpedance amplifier 100 are connected to the first port and the second port of the vector network analyzer 101, respectively. The output side terminals (third terminal, fourth terminal) are connected to the third port and the fourth port of the vector network analyzer 101.
In this state, the S parameter of the differential transimpedance amplifier 100 is measured.
Here, when the amplitude of the output wave at each terminal is b ₁ , b ₂ , b ₃ , b ₄ and the amplitude of the input wave is a ₁ , a ₂ , a ₃ , a ₄ , the S parameter is A matrix S represented by
That is, in the measurement step ST100, S ₁₁ , S ₁₂ , S ₁₃ , S ₁₄ , S ₂₁ , S ₂₂ , S ₂₃ , S ₂₄ , S ₃₁ , S ₃₂ , S ₃₃ , which are elements of the S parameter matrix S ₃₄ , S ₄₁ , S ₄₂ , S ₄₃ and S ₄₄ are measured.

Based on the S parameter acquired in the measurement step (ST100) as described above, the calculation step (ST200) is then executed.
The calculation step (ST200) includes a differential mode S parameter calculation step (ST210), a differential mode Z parameter calculation step (ST220), and a transimpedance characteristic calculation step (ST230).

In differential mode S-parameter calculating step (ST210), determining the S-parameters S _DD of the differential mode from the S parameter acquired in ST100.
Here, when the amplitude of the reflected wave in the differential mode is y ₁ , y ₃ and the amplitude of the incident wave is x ₁ , x ₃ , the S parameter S _{DD in the} differential mode is a matrix represented by the following equation: S _DD .
That is, in the differential mode S parameter calculating step (ST210), S _DD11 , S _DD13 , S _DD31 and S _DD33 which are matrix elements of the S parameter S _{DD in} the differential mode are obtained.

Y ₁ is the amplitude value of the first terminal with respect to the second terminal, and y ₃ is the amplitude value of the third terminal with respect to the fourth terminal. X ₁ is the amplitude value of the terminal 1 with the terminal 2 as a reference, and x ₃ is the amplitude value of the terminal 3 with the terminal 4 as a reference.

Then, each element of the S parameter S _{DD in} the differential mode is expressed as follows using the element of the S parameter.

Each element of the differential mode S parameter S _DD is calculated by this (Equation 3).

When the S parameter S _DD of the thus differential mode is determined, then, it obtains the Z parameter Z _DD differential mode using the S parameter S _DD differential mode (differential mode Z parameter calculating step ST220 ).
Here, the Z parameter of the differential mode is conceptually a matrix Z expressed by the following (formula 4).
V ₁ is the voltage value of the first terminal with respect to the second terminal, and V ₃ is the voltage value of the third terminal with respect to the fourth terminal. I ₁ is the current value of the first terminal with respect to the second terminal, and I ₃ is the current value of the third terminal with respect to the fourth terminal.

In the differential mode Z parameter Z _DD , Z _DD31 and Z _DD33 are expressed as follows using the differential mode S parameter S _DD .

By this (formula 5), the elements Z _DD31 and Z _DD33 of the Z parameter Z _{DD in} the differential mode are calculated.

Next, using the Z parameter elements Z _DD31 and Z _DD33 of the differential mode Z parameter, the transimpedance characteristic Z _T between the first terminal and the third terminal of the differential transimpedance amplifier is expressed by the following (Equation 6): (Transimpedance characteristic calculation step ST230).

In this way, the transimpedance characteristic Z _T is calculated. The calculated transimpedance characteristic Z _T is output to the display unit (output step ST400).

Figure 3 is a diagram showing a trans-impedance characteristics Z _T in the graph obtained using the present evaluation method.
FIG. 3 also shows the transimpedance characteristic Z _T (simulation) obtained by circuit analysis using an equivalent circuit.
As shown in FIG. 3, both agree well over a wide frequency range, and it can be seen that the transimpedance gain in the wide frequency range can be accurately evaluated by this evaluation method.

(Second embodiment)
Next, a second embodiment of the present invention will be described.
The second embodiment is characterized in that the transimpedance characteristic Z _T ^* of the optical receiving circuit 200 including the photodiode 104 is obtained.
FIG. 4 is a flowchart showing an operation procedure of the evaluation method in the second embodiment.
In the second embodiment, after calculating the transimpedance characteristic Z _T in ST230, subsequently, in ST240, the transimpedance characteristic Z _T ^* of the optical receiving circuit 200 including the photodiode 104 is calculated. That is, calculation step ST300 includes a transimpedance characteristic Z _T ^* calculation step of the light receiving circuit (ST240) Following transimpedance characteristic Z _T calculating step (ST230).

Here, the optical receiving circuit 200 is a circuit that receives and demodulates an optical signal, and performs photoelectric conversion and signal amplification of the optical signal as described with reference to FIG.
In calculating the transimpedance characteristic Z _T ^* of the optical receiving circuit 200, the arithmetic control unit 110 sets and stores the impedance _{ZPD of the} photodiode 104 calculated in advance using an equivalent circuit of the photodiode 104. In ST240, the transimpedance characteristic Z _T ^* of the optical receiving circuit 200 is calculated by the following equation (7).

The transimpedance characteristic Z _T ^* calculated in this way is displayed on the display unit 112 in ST400 (output step ST400).
FIG. 5 is a graph showing the transimpedance characteristic Z _T ^* of the optical receiving circuit.
As described above, according to the second embodiment, the transimpedance characteristic Z _T ^* including the photodiode of the optical receiving circuit can be accurately evaluated.

(Comparative example)
Next, a comparative example of the present invention will be shown.
In the above embodiment according to the present invention, in evaluating the transimpedance characteristic Z _T of the differential transimpedance amplifier 100, the S parameter of the differential transimpedance amplifier 100 is converted by the 4-port vector network analyzer 101 in the measurement step S100. Obtained by measurement.
On the other hand, as a comparative example, a 2-port vector network analyzer 201, which is most commonly used when measuring S-parameters of a differential amplifier, is used as a measurement system. It shows the case of evaluating the trans-impedance characteristics Z _T by using the parameters.

FIG. 6 shows the configuration of a measurement system that uses a 2-port vector network analyzer 201 instead of the 4-port vector network analyzer 101.
In FIG. 6, the input-side terminals of the differential transimpedance amplifier 100 are referred to as a first terminal and a second terminal, and the output-side terminals are referred to as a third terminal and a fourth terminal.
The vector network analyzer 201 in this comparative example is a two-port type, and has a first port and a second port.
The first terminal of the differential transimpedance amplifier 100 is connected to the first port of the two-port vector network analyzer 201, and the third terminal is connected to the second port.
Further, the second terminal and the fourth terminal of the differential transimpedance amplifier 100 connecting 50Ω termination resistor R _3.
In such a measurement system configuration, the S parameter is measured, and the transimpedance characteristic Z _T is calculated based on the measured S parameter.
FIG. 7 shows the transimpedance characteristics thus obtained as Z _T (2-port measurement).
FIG. 7 also shows a transimpedance characteristic Z _T (simulation) obtained by circuit analysis using an equivalent circuit of the differential transimpedance amplifier 100.

As shown in FIG. 7, the transimpedance characteristic Z _T (2-port measurement) obtained using the 2-port vector network analyzer 201 is the transimpedance characteristic Z _T (simulation) obtained by circuit analysis. It can be seen that the characteristics are completely different. In other words, the difference between the transimpedance characteristic Z _T (2-port measurement) obtained using the 2-port vector network analyzer 201 and the transimpedance characteristic Z _T (simulation) obtained by circuit analysis is only a difference of 6 dBΩ. However, the evaluation of the frequency characteristics is completely different.
As can be seen from FIG. 7, in the characteristic evaluation of the differential transimpedance amplifier, accurate evaluation cannot be performed using a commonly used two-port vector network analyzer.

Meanwhile, as described above (FIG. 3), and according to an embodiment of the present invention, trans-impedance characteristics Z _T determined by the transformer impedance characteristics Z _T and a circuit analysis determined based on measurements (Simulation) Are in good agreement over a wide frequency range.
Thus, according to the present invention, it has been shown that the transimpedance gain of the differential transimpedance amplifier 100 can be accurately evaluated in a wide frequency range.

In addition, this invention is not limited to the said embodiment, Of course, a various change can be added in the range which does not deviate from the summary of this invention.
In the above (Expression 6), an expression applicable when the termination resistance is 50Ω is shown. However, when the termination resistance is a different value, the value of 50 in (Expression 6) may be changed as appropriate. Further, in (Equation 6), an equation using the Z parameter elements Z _DD31 and Z _DD33 of the differential mode is shown, but it is equivalent even if it is replaced with Z _DD42 and Z _DD44 having a complementary relationship. Of course, it is in the range.

Further, the above-described evaluation program can be provided by being recorded on a recording medium, or can be provided by being transmitted via the Internet or other communication media. Storage media include, for example, flexible disks, hard disks, magnetic disks, magneto-optical disks, CD-ROM (Compact Disc Read Only Memory), DVD (Digital Versatile Disc), ROM (Read Only Memory) cartridges, and battery backup. A RAM (Random Access Memory) memory cartridge, a flash memory cartridge, a nonvolatile RAM cartridge, and the like are included. The communication medium includes a wired communication medium such as a telephone line, a wireless communication medium such as a microwave line, and the like.

This application claims priority based on Japanese Patent Application No. 2008-204987 filed on August 8, 2008, the entire disclosure of which is incorporated herein.

The present invention can be applied to the evaluation of transimpedance amplifiers used in optical communication receivers. For example, it receives differential phase shift keying of zero return code (RZ: Return-to-zero) as a modulation code or differential quadrature phase shift keying (DQPSK: 信号 Differential Quadrature Phase Shift Keying) Thus, the present invention can be applied to the evaluation of a differential transimpedance amplifier used in an optical receiving circuit that demodulates the signal.

100 ... differential transimpedance amplifier, 101 ... 4-port vector network analyzer, 102 ... input unit, 104 ... photodiode, 105 ... bit delay element, 108 ... bit delay interferometer, 109 ... differential amplifier, 110 ... calculation Control unit, 112 ... display unit, 200 ... optical receiver circuit, 201 ... 2-port vector network analyzer, 300 ... evaluation device for differential transimpedance amplifier.

Claims (7)

An evaluation method for evaluating the relationship between the band of a differential transimpedance amplifier to be evaluated and the transimpedance gain,
The four terminals of the differential transimpedance amplifier are connected to the four ports of the 4-port vector network analyzer, respectively, and the S parameter of the differential transimpedance amplifier is measured by the 4-port vector network analyzer.
Based on the measured S parameter, the differential mode S parameter S _DD is calculated,
The differential mode Z parameter Z _DD is calculated using the calculated differential mode S parameter S _DD ,
Evaluation method for the differential transimpedance amplifier and calculates the transimpedance characteristic Z _T of the differential transimpedance amplifier with a Z parameter Z _DD differential mode the calculated. In the evaluation method of the differential transimpedance amplifier according to claim 1,
When the input side terminal of the differential transimpedance amplifier is the first terminal and the second terminal, and the output side terminal is the third terminal and the fourth terminal,
In the calculation of the differential mode S parameter, each element of the differential mode S parameter S _DD is calculated by (Equation 1),
In the calculation of the differential mode Z parameter, the element of the differential mode Z parameter Z _DD is calculated by (Equation 2),
Wherein in the calculation of the trans-impedance characteristics Z _T, the evaluation method of the differential transimpedance amplifier and calculates at transimpedance characteristic Z _T (Equation 3).

An optical receiver circuit evaluation method for evaluating characteristics of an optical receiver circuit in which a photoelectric conversion element is connected to each of two terminals on the input side of a differential transimpedance amplifier,
The transimpedance characteristic Z _T ^* of the optical receiver circuit is calculated following the evaluation method for the differential transimpedance amplifier according to claim 1 or 2,
The calculation of the transimpedance characteristic Z _T ^* of the optical receiver circuit is as follows:
An optical receiver characterized in that an impedance characteristic Z _T ^{* of} an optical receiver circuit is calculated by the following expression that multiplies the impedance characteristic Z _PD of the photoelectric conversion element by the trans-impedance characteristic Z _T of the differential transimpedance amplifier. Circuit evaluation method.

A four-port vector network analyzer having four ports to which the four terminals of the differential transimpedance amplifier are respectively connected, and a computer as an evaluation apparatus for evaluating the relationship between the bandwidth of the differential transimpedance amplifier and the transimpedance gain Incorporate
On this computer,
A measuring step of measuring an S parameter of the differential transimpedance amplifier by the 4-port vector network analyzer;
A differential mode S parameter calculating step of calculating a differential mode S parameter S _DD based on the S parameter measured in the measuring step;
A differential mode Z parameter calculation step of calculating a differential mode Z parameter Z _DD using the differential mode S parameter S _DD calculated in the differential mode S parameter calculation step;
A transimpedance characteristic Z _T calculation step of calculating a transimpedance characteristic Z _T of the differential transimpedance amplifier using the differential mode Z parameter Z _DD calculated in the differential mode Z parameter calculation step; A storage medium storing an evaluation program for a differential transimpedance amplifier. An optical receiver circuit evaluation program for evaluating characteristics of an optical receiver circuit in which a photoelectric conversion element is connected to each of two terminals on the input side of a differential transimpedance amplifier,
A computer is incorporated into an evaluation apparatus including a 4-port vector network analyzer having four ports to which four terminals of a differential transimpedance amplifier are connected, respectively.
On this computer,
A measuring step of measuring an S parameter of the differential transimpedance amplifier by the 4-port vector network analyzer;
A differential mode S parameter calculating step of calculating a differential mode S parameter S _DD based on the S parameter measured in the measuring step;
A differential mode Z parameter calculation step of calculating a differential mode Z parameter Z _DD using the differential mode S parameter S _DD calculated in the differential mode S parameter calculation step;
A transformer impedance characteristics Z _T calculating step of calculating a trans-impedance characteristics Z _T of the differential transimpedance amplifier with a Z parameter Z _DD differential mode calculated by the differential mode Z parameter calculating step,
The transimpedance characteristic impedance characteristics Z _PD and the differential transimpedance amplifier by multiplying the trans-impedance characteristics Z _T of the optical receiver circuit for calculating the impedance characteristics Z _T ^* of the light receiving circuit of the photoelectric conversion element Z _T ^* A storage medium storing an optical receiver circuit evaluation program. A 4-port vector network analyzer having four ports to which the four terminals of the differential transimpedance amplifier are respectively connected;
The 4 together to obtain the port vector network analyzer control to S-parameters of the differential transimpedance amplifier, the arithmetic control unit for calculating a trans-impedance characteristics Z _T of the differential transimpedance amplifier, based on the S parameter And comprising
The arithmetic control unit calculates a differential mode Z parameter Z _DD using the differential mode S parameter S _DD after calculating the differential mode S parameter S _DD based on the measured S parameter. The differential transimpedance amplifier evaluation apparatus further calculates the transimpedance characteristic Z _T of the differential transimpedance amplifier using the Z parameter Z _DD of the differential mode. An optical receiver circuit evaluation apparatus for evaluating the characteristics of an optical receiver circuit in which a photoelectric conversion element is connected to each of two terminals on the input side of a differential transimpedance amplifier,
A 4-port vector network analyzer having four ports to which the four terminals of the differential transimpedance amplifier are respectively connected;
An arithmetic and control means for controlling the 4-port vector network analyzer to obtain the S parameter of the differential transimpedance amplifier, and calculating the transimpedance characteristic Z _T ^* of the optical receiving circuit based on the S parameter; With
The arithmetic control means includes
After calculating the differential mode S parameter S _DD based on the measured S parameter, the differential mode S parameter S _DD is used to calculate the differential mode Z parameter Z _DD, and the differential mode The transimpedance characteristic Z _T of the differential transimpedance amplifier is calculated using the Z parameter Z _{DD of the} mode,
Subsequently, the impedance characteristic Z _T ^* of the optical receiving circuit is calculated by multiplying the impedance characteristic Z _PD of the photoelectric conversion element by the trans-impedance characteristic Z _T of the differential transimpedance amplifier. Receiver circuit evaluation device.

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