Global Digital Step Attenuator Market By Type (IF Digital Step Attenuators , and RF Digital Step Attenuators), By Application (Test Equipment and Sensors , CATV/Satellite Set-top Boxes , Fiber Optics and Broadband Telecom , and Cellular/3G Infrastructure), By Region, and Key Companies - Industry Segment Outlook, Market Assessment, Competition Scenario, Trends and Forecast 2020-2029