| | 1 | == Orbit Noise Generator Wireless Board (WiBo) == |
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| | 3 | WiBo102 is a 4.00 x 4.00” printed circuit board (PCB) designed around a Maxim, Inc. MAX2829ETN+D radio transceiver chip. This chip incorporates most of the radio functions except for the reference oscillator, baseband I/Q amps, power amps and antenna switches. |
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| | 5 | Four antennas (A01-A04) are mounted directly to WiBo102 though provision is made for adding SMA connectors and using off-board antennas if necessary. Two antennas are primarily for transmission (Tx) and two for receiving (Rx). Antenna switching is possible for diversity gain. |
| | 6 | It is also possible to switch all Tx and Rx signals into a single antenna. |
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| | 9 | A. PCB |
| | 10 | The PCB is a 4.00 x 4.00” FR-4 four-layer controlled impedance stackup board manufactured by Advanced Circuits, Inc.(http://www.4pcb.com/index.htm). |
| | 11 | For orientation purposes, reference marks are shown along the top (A-D) and right sides (1-4) of the board in one inch increments. |
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| | 13 | Looking from the top down, the top copper layer is the component side with all the high-frequency RF transmission lines. The dielectric under this layer is 20 mils thick. The structure of the traces is coplanar waveguide with ground (CPWG). |
| | 14 | A trace width of 30 mils and gap-to-ground of 18 mils provides a very close match to a 50ohm characteristic impedance. |
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| | 16 | The next copper layer down is all ground plane. The third layer down is a signal layer with predominately vertical traces surrounded by ground plane. The fourth or bottom layer is another signal layer with predominately horizontal traces. |
