Spectral Stitching Method to Increase Instantaneous Bandwidth in Vector Signal Analyzers

Abstract

Various embodiments are described of devices and associated methods for processing a signal using a plurality of vector signal analyzers (VSAs). An input signal may be split and provided to a plurality of VSAs, each of which may process a respective frequency band of the signal, where the respective frequency bands have regions of overlap. Each VSA may adjust the gain and phase of its respective signal such that continuity of phase and magnitude is preserved through the regions of overlap. The correction of gain and phase may be accomplished by a complex multiply with a complex calibration constant. A complex calibration constant may be determined for each VSA by comparing the gain and phase of one or more calibration tones generated with each region of overlap, as measured by each of the VSAs.

Description

FIELD OF THE INVENTION[0001]The present invention relates to the field of signal processing, and more particularly to systems and methods for increasing instantaneous bandwidth in a vector signal analyzer or a vector signal generator.DESCRIPTION OF THE RELATED ART[0002]Instantaneous bandwidth is an important banner specification for all radio frequency (RF) vector signal analyzers (VSAs) and RF vector signal generators (VSGs). The desire of the industry is to increase the bandwidth as much as possible without sacrificing dynamic range. In many cases, the limiting factor in achieving the largest possible bandwidth is the sample rate of the analog-to-digital converters (ADCs) and digital-to-analog converters (DACs). While ADC and DAC vendors are always working to increase the converter rates, there still exists a desire in many applications for bandwidths that exceed the capabilities of state-of-the-art ADCs and DACs. There are several different methods within the industry for achievi...

AI Technical Summary

Benefits of technology

The patent describes a method and system for processing signals using multiple vector signal analyzers (VSAs). These VSAs are designed to analyze different frequency bands of an input signal. The VSAs are synchronized with each other and can process the signals by digitizing, interpolating, frequency-shifting, filtering, and adjusting the gain and phase. The system can also include a signal splitter and multiple parallel signal processing pathways for further processing. The technical effect of this invention is to provide a more accurate and efficient method for analyzing signals by processing them with multiple VSAs and using a complex calibration constant to correct any phase and gain mismatch between the VSAs.

Problems solved by technology

In many cases, the limiting factor in achieving the largest possible bandwidth is the sample rate of the analog-to-digital converters (ADCs) and digital-to-analog converters (DACs).

This method introduces errors resulting from inaccuracies in staggering the time alignment and from differences in the magnitude and phase between the various ADCs.

In general, it is difficult to achieve more than 8 bits of dynamic range without DSP correction.

Online methods typically have to assume something about the input signal, and other negative effects occur when those assumptions are broken.

However, this method typically creates a DC leakage spur and an image spur.

In addition, the method only scales to two converts.

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