What is the difference between the CL4490/AC4490 and CL4790/AC4790?

Answer

The CL4490 /AC4490 radio provides better performance and range due to its Client/Server architecture. This architecture enables it to maintain its connection through a beacon which is sent out in the first 1ms of each hop by the Server. Because the radios maintain their connection they can distinguish a desired signal from the noise floor with more precision, at a lower RSSI differential. This enables the radio to get better range than the CL4790/AC4790. Additionally, the CL4490/AC4490 radio has a shorter hop period of only 20ms. Each network must have one radio configured as a Server, which sends out the beacon to maintain the connection, and can have one or multiple clients. All clients must be in range of the server to operate.

The CL4790 /AC4790 radio uses a peer-to-peer (servererless) architecture, in which the devices need to re-establish a connection each time one of them needs to send data. The CL4790/AC4790 has a longer hop period of 50ms, but attempts to make up for this by having a larger packet size. Because this radio does not maintain its connection, it has to look for the signal in all the noise. As the radios get further and further apart the receiver has to try to pull the signal from the noise floor where it gets buried as the RF energy of the noise is more than the RF signal.

The CL4790 was designed after the CL4490 to fit applications which required a truly servererless architecture, where all the radios communicate as peers. It is best suited for mobile applications in which one or more of the radios will need to roam, and may go outside the range of a server, or in applications which may require a "mesh-like" or daisy-chain set up. For most point-to-point or point-to-multipoint applications the CL4490/AC4490 is the better fit.