Test systems manufacturer Ixia fell short of its expected revenues in the fourth quarter, the company said. The Calabasas-based firm had lower than expected sales from its government clients and from customers in North America and Europe. The company puts its fourth quarter revenues in the range of $40.5 million to $41.5 million. Previously stated guidance put revenues between $44 million and $48 million. The one bright spot for Ixia was in high bookings from network equipment manufacturers in Japan. While confident of its business and strategy, the company is taking cautious steps in respect to operating expenses and capital expenditures, President and CEO Atul Bhatnagar. Ixia releases its full fourth quarter financial statement on Feb. 5.