Check your sentences for faulty construction. Incorrect use of commas is a common cause of poorly constructed and excessively long sentences. The channels are combined and separated by timing circuits, not by filters. Interference between channels depends less on non-linear features of the system, because only one channel is using the common communication medium at any time. Use parentheses sparingly.
Most uses are due to sheer laziness and can be avoided by breaking up the sentence.
A paragraph should contain a single coherent idea. It is easier to read a text where paragraphs are not excessively long. You should try always to keep them to less than half a page. On the other hand, successive paragraphs which are very short may also be very difficult to read. Such an approach is often the result of poorly structured thinking.