Overview Noise Reduction Techniques I am trying to learn signal processing and when I research about ways to reduce noise in different situations it's so easy to get lost in one solution or go down the wrong path 

for example, is your noise correlated? Is it not? Is it from multiple sources? Is it not? 

I need to get some intuition on common solutions to these scenarios, but I too easily get lost in the massive amount of really specific research papers 

Can someone point me to an overview of these techniques and when to use them etc...? Any help would be useful at this point
The frequency domain conjugate multiplication (correlation) of the received signal with the reference signal followed by the power delay profile will provide you the overall signal to noise ratio. As explained in paper titled "SNR Estimation based on Sounding Reference Signal in LTE Uplink".

There are various noise reduction algorithm exist. Which will reduce the noise and will enhance the main expected signal component. There are adaptive filter which will converge to the expected value and depend on there performance, complexity is dependent. For example LMS, NLMS and RLS are the type of adaptive filters. Which will reduce the noise but the accuracy is directly proportional to the complexity. 

By filtering we can reduce the noise, but we cant remove it totally for example AWGN noise.