Nearly one in five attempts to make a mobile phone call in Norfolk is likely to be unsuccessful, an independent survey has found.

Norfolk County Council commissioned the survey earlier this year to establish a true picture of mobile voice and data coverage in the county.

Carried out between February and March this year, its aim was to work with mobile providers to improve coverage and tackle 'not spots'.

The survey, conducted by specialist company AWTG, was carried out along more than 3,400 miles of Norfolk's roads, 30 railway stations and main railway lines, enterprise zones and popular tourist sites and destination.

The main findings show:

• Only 82 percent of call attempts in Norfolk are successful. Call failures happened throughout Norfolk for all operators.

• Mobile data (3G and/or 4G) services were available in around 91 percent of locations surveyed.

• Attempts to browse the web and stream video using mobile data were successful around 85 per cent of the time. But web browsing success rates were considerably lower across all operators on 3G.

• 4G data download speeds were good compared to the national average, particularly on EE.

• 4G coverage issues were widespread.

Tom Garrod, chairman of the county council's digital innovation and efficiency committee, said: 'People have been telling us for some time that phone signal around the county isn't good enough.

'While the survey shows Norfolk is comparable to the rest of the UK in some respects, it's clear there is still considerable room for improvement, particularly in enabling people to make phone calls wherever they are in the county.'

The council said it will use the information to create an interactive map on its website.

'This will allow people to see which of the four major providers, EE, Telefonica/O2, Three and Vodafone, have the best coverage by area and for their needs,' the council said.

More detailed information about the outcome of the survey will be discussed at the county council's digital innovation and efficiency committee on Friday, May 11.

• Mobile phone providers have been contacted for comment