I am trying to figure out the power consumption of the DW1000. There are 3.3V supplies and 1.8V supplies. The Rx and TX supplies are separate. However, there is only one number given for current consumption for Rx and Tx. There are on-board linear regulators for making 1.8V, but there are options for using an external switching regulator. There also seems to be an on-board switching power supply. It will take me a while longer to figure it out.
The spec provides a recommended PCB stackup and routing for part of the RF section. They specify a chip antenna: http://www.digikey.com/product-detail/en/AH086M555003-T/587-2204-1-ND/2002902. It’s 8mm x 6mm x 1mm. That must be the antenna off to the side of this board.
I think they show the same side of the board twice but one photo has the RF shield installed.
This is the recommended RF layout.
There’s almost enough information to design our own board.
The modules will be available in mid-June from Digikey. Maybe if one were to beg and pay lots of money one or two could be had now directly from DecaWave, but it’s less than two months away.
It’s better to use the modules from the standpoint of knowing they are wired up correctly and the layout is correct etc – but they are not plug-and-play. Either a mess of wires has to be soldered onto the sides of the module or a motherboard has to be made to hold the module.
The module has a chip antenna. It’s the device that says “T03” on it. The eval kit has an SMA connector the the dog-ear antenna screws on to.
Designing an antenna into a wrist band must be a very difficult task. Perhaps that’s a good reason to try to do it.
I don’t think the UWB will interfere with the BLE signal since they are not the same frequency but I don’t know much about it. There’s a good way to find out.
How small do you want our first DW-BLE board to be? Wrist-worn enclosure-sized?
dweeble.com – taken
dooble.com – taken
dewble.com – available
dewbly.com – available
dewable.com – taken
blebug.com – available
blebugger.com – available
buggerme.com – taken
Since I’m generally clueless and don’t know about the pitfalls, I don’t think making our own board is such a big deal. The hard part is selecting the right microcontroller and interfacing it with the DW1000. The antenna can be either the chip antenna or copy their dog ear, or connect any suitable UWB antenna to an SMA or SMP or whatever. If we make our own board it can have a large breadboarding area, and desired connectors.
The DW ST1000 PowerPoint shows a header with JTAG, USP and SPI. The uC is an ST32F105. $600 for two boards feels like robbery. However, you could connect up other stuff to it as long as it’s SPI. It would be the fastest way to try it out, and in the long run perhaps the least expensive. One big issue is the high-gain antenna won’t give real-world (chip antenna) results.