DME

Question 1

DME

Answer 1

Distance Measure Equipment
2 pulses
measure slant range A/C to beacon

Question 2

SCHEME

Answer 2

interrogator AC

transponder ground

Question 3

transmission

Answer 3

UHF 962 to 1213 MHz
code P - 0 - N
Vertical polariz
Tx and Rx always separate +- 63 MHz to avoid false read from ground reflection

Question 4

use

Answer 4

position fixing
supplementary AID for holding and instrument approach
G/S measure

Question 5

how work

Answer 5

series of pulses
intervall btwn pulses in each pair is constant
intervall between pairs is random( Jittered prf)
transponder answer with 50 microsecond of delay

Question 6

range

Answer 6

time from Tx to Rx - 50 microsecond

Question 7

avoid problems

Answer 7

63 MHz avoid read false target from the ground
Jittered PRF avoid use signal destinate to other A/C
2 pulse avoid confusion with other radar

Question 8

search and lock on

Answer 8

at the instant of Tx the receiver set up gates that match the jittered prf in order to filtrate the other signal Trx prf= 150 pps
only response that match the gate are made pass and receiver lock on the target with 24pss

Question 9

beacon saturation

Answer 9

has a limited capacity of 2700 pps
in case of saturation is gonna to keep the 100 strongest signal
18 in search mode
112 lock mode a max of 100

Question 10

accurancy

Answer 10

+- 0.25 NM + 1.25% distance

Question 11

TACAN

Answer 11

military all UHF can be use as dme

Question 12

ASSOCIATED

Answer 12

terminal d <30 m
en route d<600 m
same identification 
different tone
frequency pare

Question 13

servinc same location but too far

Answer 13

same letter but the DME finish with the letter Z

frequency pared

Question 14

different location

Answer 14

over 6 NM
different ident
no pareid

Question 15

RHO/RHO FIX

Answer 15

use the DME and

Question 16

RHO-THETA FIX

Answer 16

VOR + DME