Shares in Ubisense dropped sharply on Friday after the business services group said that a revenue shortfall in the first half would unlikely be recovered.The AIM company, which specialises in so-called 'Enterprise Location Intelligence' solutions, had previously announced the slippage of two major contracts into the second half but has now revealed further delays in signing certain contracts.As such, revenues in the higher-margin Solutions division will "now be some way short of that achieved in the first half of 2014"."Although the majority of the contracts which have slipped are expected to be closed during the second half, the board believes it is prudent to plan on the basis that the H1 revenue shortfall is unlikely to be recovered in full in the second half of 2015," Ubisense said.The company also said that a review of the business and its costs has led to the conclusion that a restructuring is needed to drive operational profitability. This restructuring is expected to result in one-off charges but deliver "significant ongoing cost savings", it said.The stock was down 13.1% at 96p in early deals.