The Glasgow-based company, which helps telecoms firms develop the infrastructure needed to run mobile phone services, is preparing for a big increase in demand for its services, as operators upgrade their networks to cope with the ever increasing popularity of mobile devices, such as smartphones and tablets, and associated applications, such as video messaging.
Chief executive Brian Dougherty said: "The mobile telecoms market is currently experiencing a period of unprecedented activity driven by a combination of the introduction of 4G services and the consolidation of the operators' radio networks."
Mono has forecast turnover of £40m in the current year. It had sales of £36.2m in the year to August 2013.
The company increased pre-tax profits to £4m in the year to August from £2.7m in the preceding year. It has more than 200 employees.
Kevin Lyon, former head of private equity firm 3i's operations in central Scotland, is chairman of Mono's holding company. Mr Lyon and Mr Dougherty are shareholders in the holding company, Mono Global Group.
Mr Dougherty said Mono has an excellent and supportive relationship with its bank, HSBC. He added: "The longer-term predictability that is provided by BGF's growth capital enables us to accommodate the mobilisation and working capital requirements of the ... opportunities that are available to us."
The investment is the eleventh made in Scotland by the bank-backed Business Growth Fund.
Established following complaints lenders were failing to support small and medium sized enterprises, the £2.5bn Business Growth Fund opened for business in April 2011.
Mono was created through a combination of the telecoms consultancy arm of surveyors James Barr and infrastructure adviser Ingenco in a £13m deal backed by 3i in 2002.