Tenna Systems, a defense technology company pioneering software-driven spectrum intelligence, announced it has raised an oversubscribed $13.5 million seed funding round led by Costanoa, with participation from Viola Ventures, Fresh Fund, 202 Ventures and existing investors. The new funding will accelerate Tenna's expansion in the U.S. defense market, where the company has already partnered with government agencies and prime contractors to deliver hardware-free spectrum intelligence for wireless-dependent systems at global scale.