Custom Arb Waveform Generator

Working with Filters

middle, and total attenuation at high frequencies. The width of the middle frequencies is defined by the roll off factor or Filter Alpha (0 < Filter Alpha < 1).

Gaussian is a Gaussian pre- modulation FIR filter.

User FIR enables you to select from a Catalog of FIR filters; use this selection if the other

predefined FIR filters do not meet your needs. For more information, see Define User FIR, below.

Rectangle is a rectangular pre- modulation FIR filter.

APCO 25 C4FM is an APCO 25- specified C4FM filter; this is a Nyquist filter with an alpha of 0.200 that is combined with a shaping filter.

Filter Parameters

Define User FIR is available for when the predefined FIR filters do not meet your needs. You can define FIR coefficients and set the oversample ratio (number of filter coefficients per symbol) to be applied to a custom FIR filter.

Filter Alpha enables you to adjust the filter alpha for a Nyquist or root Nyquist filter. If a Gaussian filter is used, you will see Filter BbT; this softkey is grayed out when any other filter is selected.

(Custom Realtime I/Q Baseband Only) Optimize FIR for EVM ACP enables you to optimize a Nyquist or root Nyquist filter for minimized error vector magnitude (EVM) or for minimized adjacent channel power (ACP); the softkey is grayed out when any other filter is selected.

Restore Default Filters replaces the current FIR filter with the default FIR filter for the selected format.

Using a Predefined FIR Filter

Selecting a Predefined FIR Filter

 

 

 

1.

Preset the instrument: Press Preset.

 

 

 

2.

Press Mode > Custom > ARB Waveform Generator

> Digital Mod Define

> Filter

> Select

 

or

 

 

 

 

Mode > Custom > Real Time I/Q Baseband > Filter > Select >

 

 

3.

Select the desired filter. If the filter you want is not in the first list, press More (1 of 2).

Adjusting the Filter Alpha of a Predefined Root Nyquist or Nyquist Filter

 

 

1.

Preset the instrument: Press Preset.

 

 

 

2.

Press Mode > Custom > ARB Waveform Generator

> Digital Mod Define

> Filter

> Filter Alpha

 

or

 

 

 

 

Mode > Custom > Real Time I/Q Baseband > Filter

> Filter Alpha

 

 

3.

Enter a new Filter Alpha value and press Enter.

 

 

Adjusting the Bandwidth-Bit-Time (BbT) Product of a Predefined Gaussian Filter

 

1.

Press Mode > Custom > ARB Waveform Generator

> Digital Mod Define

> Filter

> Select > Gaussian

 

or

 

 

 

 

Mode > Custom > Real Time I/Q Baseband > Filter

> Select > Gaussian

 

 

2.Press Filter BbT.

3.Enter a new Bandwidth- Bit- Time (BbT) product filter parameter and press Enter.

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Agilent Technologies E8257D PSG Using a Predefined FIR Filter, Selecting a Predefined FIR Filter, Filter Filter Alpha

E8267D PSG, E8257D PSG specifications

Agilent Technologies, a recognized leader in electronic measurement and communications solutions, offers a comprehensive range of signal generators, including the E8257D PSG (Pulsed Signal Generator) and E8267D PSG. These instruments are engineered to meet the demanding requirements of wireless communication, aerospace, defense, and various research applications.

The E8257D PSG is known for its versatility and reliability. It operates within a frequency range of 250 kHz to 40 GHz, making it suitable for a wide array of applications, from signal generation to vector modulation. With an output power capability of up to +30 dBm, it delivers high-quality signals with exceptional precision. Its low phase noise performance is especially critical for applications such as radar and communication system testing, where signal integrity is paramount.

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On the other hand, the Agilent E8267D PSG is designed to cater to the needs of users requiring a combined signal generation and analysis solution. With the capability to generate signals from 250 kHz to 67 GHz, the E8267D is ideal for millimeter-wave applications, as well as testing next-generation wireless technologies.

This model includes features such as enhanced phase noise performance and faster switching speed, which are crucial for signal integrity in sophisticated networks. The instrument's intuitive user interface and powerful software integration facilitate effortless operation and automation, thereby improving workflow efficiency.

Both the E8257D and E8267D PSG instruments incorporate cutting-edge technologies such as low-noise microwave and RF components, as well as digital signal processing capabilities. They provide users with enhanced accuracy and reliability in their measurements.

In summary, Agilent Technologies' E8257D and E8267D PSG signal generators represent the pinnacle of precision in signal generation technology. With their extensive feature sets, advanced modulation capabilities, and robust performance specifications, these instruments are invaluable tools for engineers and researchers working across various high-tech industries.