This guide provides a technical overview of signal generators offered by Keysight Technologies, Inc., detailing their selection from baseband to 67 GHz, with frequency extensions up to 1.1 THz. It outlines the performance capabilities of various signal generators, including their modulation capabilities, which range from general-purpose AM, FM, and digital I/Q to specific formats such as GSM, W-CDMA, HSPA, LTE, LTE-Advanced, 5G NR, GPS, and WLAN. The document categorizes signal generators into benchtop and modular PXI types, explaining their suitability for different applications, such as R&D and design verification. Additionally, it presents a comparison of key specifications for benchtop vector and analog signal generators, as well as modular signal generators, highlighting their frequency ranges, output power, and modulation capabilities. The guide aims to assist users in selecting the appropriate signal generator for their specific needs, supplemented by online tools available at Keysight's website.