X Band Current 
SX both S & X Band Current 

Standby 
0.4Ah / 0.6W/h 
0.6Ah / 0.9W/h 
1 Radar 
0.5Ah / 0.74W/h 
1.2Ah / 1.8W/h 
10 Radar at same time 
1.5Ah / 2.5W/h 
3.2Ah / 4.8W/h 
100 Radar at same time 
11.5Ah /17 W/h 
24Ah / 35W/h 
A good option would be to pick a system between the 10 and 100 radar range to ensure good operation even in busy periods, but this will depend upon the traffic intensity.
The following calculations were used and make an assumption of radar parameters as follows.
X Band PRI 1KHz, Pulse width 1uS antenna Beam width 3 degrees, antenna rotation 25rpm.
S Band PRI 700Hz, Pulse width 2uS Antenna Beam width 5 degrees, antenna rotation 25rpm.
In standby without any radar interrogations the RTE will take the following current from the battery
X Band Current 
SX both S & X Band Current 

Standby 
8mA 
12mA 
1 Radar 
10.25mA 
24.5mA 
10 Radar at same time 
30.6mA 
65.7mA 
100 Radar at same time 
234mA 
481mA 
This would equate to a daily use of the following
X Band Current 
S & X Band Current 

Standby 
192mAh 
290mAh 
1 Radar 
246mAh 
588mAh 
10 Radar at same time 
735mAh 
1,578mAh 
100 Radar at same time 
5,615mAh 
11,536mAh 