User's Manual

2016-03-18

NUR-10W HW Implementation Guide v1.4

second one to be “antenna control 2”. Via the SW API it’s possible to select which of the connected

antennas are enabled and used or let the module automatically switch between them.

Table 19. 4 Port antenna control truth table.

8 DIAGNOSTIC FUNCTIONS

8.1 REFLECTED POWER MEASUREMENTS

This measurement can be used to check what is the matching of the antenna(s) and feed line(s). When this

function is triggered will NUR-10W module put carrier wave ON at full power and then measure the

absolute power level that is coming to receiver port. Attenuation in the RX-line is 11 dB between the

measuring point and RF-pin.

Leakage cancelation circuitry will try to cancel the self jammer signal reflecting back from the antenna or

coming directly from coupler. So this value cannot be used to calculate the absolute antenna S11 value. For

good performance reflected power value should be below zero and lower then -10dBm means almost

perfect isolation between transmitter and receiver

8.2 CHANNEL SCANNER

This function can be used to monitor the interferences in the current frequency band. It is also useful if you

want to check if some fixed channel is in use. When you trigger this function NUR-10W will scan all the

channels in current region and return the RSSI-value of each channel. Returned values are absolute power

levels in receiver. Loss between RF pin and receiver is 11 dB so actual values are about 11dB higher.

8.3 RECEIVED SIGNAL STRENGTH (RSSI)

When reading a tag NUR-10W module also returns received signal strength indication values if wanted. Two

values are returned per one tag. One is the absolute power level (dBm) and second is the scaled power level

Case (selected antenna)

antenna control 1

antenna control 2

0 (antenna 1)

low

1 (antenna 2)

high

low

2 (antenna 3)

low

high

3 (antenna 4)

high