Calabasas-based performance test equipment company Ixia reported a revenue increase of 26 percent in first quarter results compared to the same period last year. For the first quarter ended March 31, the company reported net earnings of $7.1 million or $.10 per diluted share on revenues of $78.5 million compared with net earnings of $0.9 million or $0.01 per diluted share on revenues of $62 million for the 2010 first quarter. “We are very pleased to report strong results for our first quarter of 2011, including non-GAAP gross margin of over 80 percent and non-GAAP operating margin of over 22 percent,” commented Atul Bhatnagar, Ixia’s president and chief executive officer. “We continue to realize more operating leverage out of our model as we scale our business and in the first quarter of 2011, we reported our highest non-GAAP operating margin in over four years.” Ixia ended the first quarter with approximately $354 million in cash and investments, compared with $339 million at December 31, 2010.