I don't get how the gyroscope is used in missile guidance.
How is the gyroscope mentionned in this article pointing at Kiev? How do you read it on the gyroscope and how is the position 'set' in the device?
Actually, the gyroscope will give your angular rotation. It can be achieved through different technics (MEMS gyro, mecanical gyro...) but the final goal will always be to give you your angular rotation.
You need your angular rotation and the specific forces applied to your body (given by the accelerometers) to be then able to compute your position, speed... in the earth frame called NED (North East Down).
That's the very short version. You also need to know your Lla position to correct your gravity model, the error model of your sensor to correct them... Kalman filtering is always used (in my experience).
Kalman filtering can be overhelming but the course from D.Alazard is really great (still using it after 3 years in navigation field).
If you want a quick exemple, a north finder algo is very easy to understand (basic earth projection). It is also the first step of initialisation of a navigation system.
