does the dw1000 can be used in Japan ? , i saw a note in japan permitted frequency that ,in the frequency range of 3.4 - 4.8 .the data rate should be a minimum of 50 Mbps. and the device only supports maximum data rate of 6.8 Mbps, can we use dw1000 in Japan?
The Japanese UWB regulations:
The English translation is ambiguous in several places and the original Japanese is controlling, and I don’t read Japanese, so I can’t be definitive as to what everything means. For example, the spectrum charts show a limit line for “unwanted emissions” which suggest “wanted” ones have different limits? With that disclaimer, here is what I think the Japanese regulations mean:
The DW1000 is not generally capable of practical operation in compliance with the Japanese regulations due to severe transmit power limitations, -70 dBm/MHz generally. At that power level, range would be very short indeed, so those power levels are not practical. There are two regions where the transmit power can be higher, up to the typical -41.3 dBm/MHz, namely 4.2 to 4.8 GHz and 7.25 to 10.25 GHz.
The first region, 4.2 to 4.8 GHz, channel 3 effectively, requires “interference mitigation”, which is similar to what ETSI calls “detect and avoid (DAA)”. The system has to listen for other radio sources using the band and then if they are detected, not use the band. The “listening” has to be done within certain technical criteria which are pretty severe, including detecting a signal as weak as -136 dBm. The DW1000 is not equipped to do that, so the 4.2 to 4.8 GHz band is not available due to lack of this feature, and even if it did exist, the detection of any other source renders the system inoperative, which makes for a mostly useless option to use this band.
The second region, 7.25 to 10.25 GHz, has no “interference mitigation” requirement, but is above the frequency the DW1000 is nominally capable of. At one time, we had some ideas on how to make the DW1000 work above 7.25 GHz but we never actually ran the experiments to see if that was possible. With the imminent existence of the DW3000, the need to push the DW1000 has been removed, so that work will never be done. The DW3000 doesn’t have interference mitigation or DAA either, but since it can operate at 8 GHz, channel 9, it can be used in Japan.
You noted the “50 Mbps” requirement from section 3.2(4). Since that applies to the band 3.4 to 4.8 GHz only, and the DW1000 can’t use that band, it is no factor. The 7.25 GHz to 10.25 GHz band doesn’t have the 50 Mbps requirement.
In short, you need the DW3000, operated on channel 9, 8 GHz, to legally operate in Japan.
Mike Ciholas, President, Ciholas, Inc
3700 Bell Road, Newburgh, IN 47630 USA
+1 812 962 9408
When the DW3000 will be available in market for purchase?
Actually we are going to develop RTLS system for working mainly in India and Japan,I think DW3000 is suitable for that ,when DW3000 will be available in market ,Or is there any way to get modules with DW3000 chipset for development purpose before it is available in market