The Black Stars reached this stage in each of the last six tournaments but have not lifted the trophy since 1982 and was beaten by Cote d'Ivoire in the 2015 final.
Avram Grant's side, which beat DR Congo 2-1 in the last round, has looked one of the most convincing in Gabon but it has a poor record against Cameroon in the competition, having failed to win any of their three previous encounters.
But Gyan, who hopes to be available after a groin problem, is confident that his side can find a way past a team who upset favourite Senegal in the quarter-finals on penalties.
"The team is motivated and what we want is a win against Cameroon, who have been playing as a unit," he said.
"We all know many people thought Senegal would beat them but they proved a hard nut to crack.
"It doesn't really matter how we play as long as we get that win, because we feel it's time we make our fans happy by going all the way in the tournament. That's our main focus."
Fabrice Ondoa saved a penalty from Liverpool's Sadio Mane to see Cameroon into the last four at Senegal's expense and continue their unlikely push for the trophy.
Head coach Hugo Broos is already proud of his young side but says they proved with their quarter-final display that they will be no pushovers against a fancied Ghana side.
"It looks a very difficult game," he said. "When you look at the Ghanaians, who have been in the semi-finals for the last six tournaments, it means that they're a team constantly on with their job.
"It's a very young team. Fourteen of my players have never played at the tournament.
"But when I look at them, I'm very happy with their level of progress. Our motivation is very big. We saw that against Senegal."
- This is a re-run of the 2008 African Cup of Nations semi-final; Cameroon claimed a 1-0 victory on that occasion prior to losing in the final.
- The last three times Cameroon reached the semi-finals of the African Cup of Nations, they have progressed to the final.
- Cameroon's last four goals at the AFCON have all come from outside the box while the last three conceded by Ghana have been from outside the penalty area.
- Cameroon come into this game without a goal in their last two AFCON matches, failing to score with any of their last 23 shots in the tournament.
- Cameroon's Benjamin Moukandjo has created 15 chances in the 2017 African Cup of Nations; four more than any other player.
- At least one of the Ayew brothers has been directly involved in 10 of Ghana's last 14 goals at the AFCON (five goals and two assists for Andre, two goals and an assist for Jordan – never assisting each other in that time).