Custom Arb Waveform Generator

Working with Modulation Types

Creating a QPSK I/Q Modulation Type User File with the I/Q Values Editor

In I/Q modulation schemes, symbols appear in default positions in the I/Q plane. Using the I/Q Values editor, you can define your own symbol map by changing the position of one or more symbols. Use the following procedure to create and store a 4-symbol unbalanced QPSK modulation.

1.Press Preset.

2.Press Mode > Custom > Real Time I/Q Baseband > Modulation Type > Define User I/Q > More (1 of 2) > Delete All Rows > Confirm Delete All Rows.

This loads a default 4QAM I/Q modulation and clears the I/Q Values editor.

3.Enter the I and Q values listed in the following table:

Symbol

Data

I Value

Q Value

 

 

 

 

0

0000

0.500000

1.000000

 

 

 

 

1

0001

−0.500000

1.000000

 

 

 

 

2

0010

0.500000

−1.000000

 

 

 

 

3

0011

−0.500000

−1.000000

 

 

 

 

a.Press 0.5 > Enter.

b.Press 1 > Enter.

c.Enter the remaining I and Q values.

As the I value updates, the highlight moves to the first Q entry (and provides a default value of 0) and an empty row of data appears below the first row. As the Q value updates, the highlight moves to the next I value. As you press the numeric keys, the numbers display in the active entry area. If you make a mistake, use the backspace key and retype.

Also note that 0.000000 appears as the first entry in the list of Distinct Values, and that 0.500000 and 1.000000 are listed as the distinct values.

4.Press More (2 of 2) > Display I/Q Map.

An I/Q State Map is displayed from the current values in the I/Q Values table.

The I/Q State Map in this example has four symbols. The I/Q State Map uses the following four unique values: 0.5, 1.0, −0.5, and −1.0 to create the four symbols. It is not the number of values that defines how

many symbols a map has, but how those values are combined.

5.Press Return.

When the contents of an I/Q Values table have not been stored, I/Q Values (UNSTORED) appears on the display.

Chapter 6

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Agilent Technologies E8257C PSG, E8267C PSG, E8247C PSG CW manual
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E8267C PSG, E8247C PSG CW, E8257C PSG specifications

Agilent Technologies, a leading provider of electronic test and measurement equipment, offers a range of signal generators that are pivotal in various applications, including telecommunications, aerospace, and research. Among their top-tier offerings are the E8257C PSG, E8247C PSG CW, and E8267C PSG. These signal generators are known for their exceptional performance, flexibility, and cutting-edge technologies.

The E8257C PSG is a high-performance microwave signal generator capable of generating signals from 10 MHz to 40 GHz. Its versatility makes it ideal for applications such as radar and satellite communications. One of the standout features of the E8257C is its low phase noise and superior output power, which ensure high-quality signal generation. The instrument incorporates advanced digital signal processing technology, allowing users to create complex modulated signals with precision. It also boasts a comprehensive set of modulation formats, including AM, FM, PM, and pulse modulation, making it suitable for diverse testing scenarios.

The E8247C PSG CW is designed specifically for continuous wave (CW) applications, covering frequencies from 500 kHz to 20 GHz. This generator is optimized for high stability and low output noise, making it ideal for applications that require a reliable signal source, such as manufacturing testing and maintenance of communication systems. The E8247C features a compact design and is equipped with an intuitive user interface, allowing quick access to essential functions. Its frequency agility and fast switching capabilities enhance productivity, enabling engineers to optimize their workflow.

The E8267C PSG delivers unparalleled performance in the microwave frequency range of 250 kHz to 70 GHz. It includes advanced modulation capabilities, allowing users to generate complex waveforms with relative ease. The E8267C supports various digital modulation schemes, including QAM, which is crucial for testing modern communication systems. Its high output power and excellent spectral purity make it suitable for both R&D and manufacturing applications. Additionally, the E8267C features built-in functionality for frequency and power sweeps, providing users with extensive testing options.

In summary, Agilent Technologies’ E8257C, E8247C, and E8267C signal generators are integral tools for professionals seeking high performance and versatility in their testing environments. With unique features and advanced technologies, these generators cater to the demands of modern applications, ensuring reliable and accurate signal generation for a wide range of industries. Whether it's for research, development, or manufacturing, these instruments demonstrate Agilent's commitment to delivering top-notch testing solutions.
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