I am testing the DW1000 with external power amplification. For this we have followed the documents APS009 (Operating the DW1000 Under LAES Regulations) and APS004 (Increasing the Range of DW1000 Based Products using an External LNA).
Inspecting the test devices on a spectrum analyser we can see that the profile does not meet the spectrum mask for LAES defined in ETSI EN 302 065-2 v2.1.1 (2016-11), Ch 4.3.2 Table 3. In this table the frequency breakpoints and mean spectral density (dBm/MHz) are very challenging (20dB steps). We are using the supported channel 2 (3.993.6MHz, 499.2 MHz BW). The ETSI defined mask is defined as:
3.1 < f ≤ 3.4: -70 dBm/MHz
3.4 < f ≤ 4.2: -21.3 dBm/MHz
4.2 < f ≤ 4.8: -41.3 dBm/MHz
The problem seems to be that the fixed supported channels (CH1 or CH2) do not allow operation within this mask/constraint. It seems that a unsupported Channel around 3.65GHz is needed and a narrower bandwidth than 500MHz.
In the document APS009 this challenge is referred to but additional information is not provided: “The European LAES regulations specifically restrict operation to the frequency range of 3.4 to 4.2 GHz. In order to be fully compliant with the ETSI LAES spec it is necessary to modify the pulse shape used in the DW1000 transmitter so that the resulting spectrum fits correctly within the LAES spectrum mask. Contact Decawave for further details on this topic.”
Please could you provide the additional details on how the DW1000 transmitter can be configured/modified to fit within the 3.4 to 4.2GHz frequency range?
Is it possible to defined unsupported Channels in the DW1000 (i.e. define own centre frequencies)?
How can bandwidth be reduced (PG_DELAY) to fit the LAES mask and what is the impact on device accuracy of positioning?
Many Thanks.