short miso and mosi pins in 3 wire spi
The ADF7020-1 has two digital interfaces. 



DATA CLK and DATA I/O are for data to be sent or received on the RF link (0.15 to 200 kbps). This isn't an SPI interface. You need to connect this to something that can continuously stream data at the rate of your RF link. If you are connecting this to a micro, you probably want these pins connected to GPIOs, and DATA CLK triggering a high-priority interrupt (based on a very quick look at the datasheet).

On page 26 in the datasheet, they say there are drivers available for a couple of ADI microcontrollers. Even if you aren't using these devices, it might be worth looking at the code they provide for hints on how to program your micro.

SLE, SCLK, SDATA, and SREAD are an SPI interface (as far as I can tell from a quick read of the datasheet). SDATA would connect to MOSI and SREAD connects to MISO. I don't see any reason you should want to connect MOSI and MISO to each other.