WARP Project Forums - Wireless Open-Access Research Platform

It depends pretty heavily on what kind of system you are building. If you aren't using OFDM, is the system narrow band? If so, you might not even need channel estimation (see these course materials for an example physical layer that uses differential encoding to avoid having to do channel estimation).

Fundamentally, channel estimation is just the act of sending something known to both the transmitter and receiver. When the receiver gets it, it is able to compare what was received against what was expected to figure out how the channel affected it. Using that information it can infer how the channel will affect the part of the transmission it doesn't a priori know. There are many of ways to achieve this concept.