However, the provider of test, assurance, and analytics solutions for next-generation telecoms devices and networks said its customers continue to invest in 5G-related infrastructure, devices and services, a trend expected to keep up in 2021.
In the year to December 31, 2020, revenue rose 4% to US$522mln while adjusted operating profit is expected to be in line with the consensus of US$98-107mln.
Adjusted operating margin increased to almost 20% from 18% in 2019, with cash at year-end of US$241mln, so the company is reviewing whether to pay a dividend.
The FTSE 250 firm secured some contract wins across the portfolio in the final quarter of 2020, benefitting from strong growth in 5G network-related activity.
There was some delay for high-speed Ethernet testing from service providers as COVID-19 impacted customer spending, bt Connected Devices revenue grew ahead of expectations due to strong demand for the new 5G device testing.
Analysts at Liberum said they believe the review of capital allocation could result in a special dividend as in the past, while Spirent "is well-positioned to show steady growth in 2021 and beyond with flat to rising margins and strong cash flows".
Shares rose 1% to 264.5p early on Monday.
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