2.4 GHz. 4 Way N connector Power splitter

Type:                                        Four -way power divider, N (F-F-F-F-F),

Connectors:                                5 N-sockets,

Frequency:                                800 - 2500 MHz.

Application:                               AFU+WLAN

Type:                                          ASP-003N

Impedance:                              50 ohms

Power:                                      10 0 W

VSWR:                                     < 1.25

Insert absorption:                         < 0.5 dB

Distribution absorption:                 6 dB

When using a splitter one has to consider the effect that the transmit power is divided equally between the antennas. I.e. with a 2-way combiner each antenna only receives 50% of the total power, with 3-way splitters about 33%, with 4-way splitters 25%. This relates to -3dB, -4.5dB or -6dB respectively, so you can use larger antennas before reaching the legal limit.
The received energy is combined and fed to the common connector of the splitter. This works usually without problems, unless the antenna segments overlap. In this case the antennas should be connected by cables of exactly the same lengths.
Of course a splitter introduces some insertion loss, but these are about 0.2 to 0.5 dB and therefore negligible.

Note: if you use a power splitter and leave some ports open, these ports must be terminated with a 50 ohms coax resistor.