AEgbert
commented
1 year ago Taking a look at the frequency-based results for FSP.1, I see that channel 15's restriction is related to a -11.4 dBm/MHz upper bound between 5930-5990 MHz (lines 18-27 of AFCS.FSP.1_mask.json). Assuming that the channel power will be uniform across the AFC device's 160 MHz bandwidth (no more than -11.4 dBm/MHz throughout the entire channel), then integrating this power density over 160 MHz leads to a channel EIRP of 10.64 dBm (-11.4 dBm/MHz -> 0.0724 mW/MHz * 160 MHz = 11.591 mW -> 10.64 dBm). This matches the mask's 10.7 dBm EIRP limit for channel 15.
Meanwhile, the primary limit for channel 143 is related to the -38 dBm/MHz upper bound between 6640-6650 MHz (lines 118-127 of AFCS.FSP.1_mask.json). Following a similar process, a -38 dBm/MHz limit over 160 MHz leads to a channel EIRP of -15.96 dBm. This matches the mask's -16 dBm EIRP limit for channel 143.
While I've not delved into the creation of the frequency-based response limits and why different PSD limits exist for the frequency ranges of those two channels in the first place, my guess is that at least part of the PSD limit difference is due to the incumbent being protected operating over differently sized bandwidths for the two channels, which leads to different noise levels N to which the I/N threshold is applied. (See WINNF-TS-1014 R2-AIP-02, which specifies a value of N in dBm/MHz, which needs to be scaled to the bandwidth under consideration before its use in R2-AIP-16).
Does this address your question about the difference in max EIRP for channels 15 and 143? If not, I can try to find someone who may be able to provide some more insight into how the frequency-based availability was derived.
sbasu07
Hi, I am trying to implement the functionality of an AFC system. As a first step, I have implemented freespace pathloss model and I am trying to match the response output for test vector 1 in the AFC System (SUT) Compliance Test Vectors v1.2 document (Incumbent proximity <=30m) I have followed the these steps:
=> PSPD, Tx = I/NRx, Est +N + LPropagation, Rx + LBEL + LFS, Feeder - GRx, Effective And, PSPD, Tx = Transmit EIRP of SPD I am trying to find the maximum EIRP of SPD by using the maximum I/N ratio at Receiver (-6 dB)
Observing the incumbent data from FR.dat file I found that incumbent is present in 9.07m distance from the SPD, operating in both channel number 15 and 143 (in Global operating class 134). But the response mask shows 26 dB difference in maximum EIRP value. The following is a snapshot of the response mask in AFCS.FSP.1_mask.json file:
What is the parameter that is causing such a huge difference in the EIRP values in freespace testcase? Is there any other parameter to be considered than those mentioned in equation?