@kevalmorabia97

Yes its better to use batch norm for 3000 dim features. Your 4 dim are bounding box location? Try normalizing both. Otherwise that will leads to abrupt result.

Try it(Not sure if It will work in your case)…
1.Use Upsampling(deconv) layers to increase the dimension of 4 dim.
2. Reduce the dimension of 3000 by using conv. I think if you try flattening kind then you will miss a lot of information.
Please explain a little more about the 3000 dim features.Because concatenation in your case sounds little different to me.