Distance Measuring Equipment Distance Measuring Equipment (DME) Distance Measuring Equipment provides Accurate Slant Range using secondary radar principle Combination of VOR and DME is an ICAO approved equipment for Airways TACAN is military equipment equivalent to DME that is installed in military airfields providing same indications in flight deck Radar Mile Radar Mile is the time taken for a Pulse to travel 1 NM and return back to radar calculated using speed of radio waves Since, 1 Radar Mile = 12.36 Micro Seconds One way Distance to the target in…
Category: Radio Navigation
Radio Aids for Navigation is an important subject for Student Pilots. In this section, you can learn about the various Radio Navigational Equipments used in Aviation.
Secondary Surveillance Radar SSR)
Secondary Surveillance Radar Principle of Secondary Surveillance Radar (SSR) SSR provides positive identification of aircraft in the line of sight on the UHF band frequencies with active co-operation of target Secondary Surveillance Radar detects aircrafts at higher range using lower power on the principle of interrogation and response SSR Ground Based Interrogator Interrogator of SSR is a ground-based equipment transmitting on 1030 MHz in horizontal plane in a specified direction SSR Interrogator has a flat directional antenna mounted on top of primary radar antenna to synchronise with primary radars The…
Airborne Weather Radar (AWR)
Airborne Weather Radar Airborne Weather Radar (AWR) Airborne weather radars installed on aircrafts provides information on weather, clouds and terrain mapping AWR can be used for fixing position in range and bearing from ground feature Consists of a transmitter, receiver, antenna and display with control panel Heating elements in the radar housing helps in reducing icing risk Airborne Radars use Flat Plate Slotted Array Antenna on a Gyro Stabilised Platform to maintain antenna horizontal during Pitch and Roll Advantage of Flat Plate antenna include Narrow Beams, Lesser Power and Side…
Ground Based Radar
Ground Radar Types of Primary Ground Radars Ground based Primary Radars are used in Air Traffic Control Area Surveillance Radar (RSR) En-route Surveillance Radar (Same as RSR) Terminal Surveillance Radar (TSR) Aerodrome Surveillance Radar (ASR) Precision Surveillance Radar (PAR) Aerodrome Surveillance Detection Equipment (ADSE) Airport Surface Movement Radar (Same as ASDE) Area (En-route) Surveillance Radar (RSR) Area Surveillance Radars are long-range radars Used by Area Control Centre (ACC) for monitoring air routes Frequency: 600 – 3000 MHz Wavelength: 10 – 50 Cm PRF: 250 PPS Pulse Length: 2 – 4…
Radio Detection and Ranging (Radar)
Radar Primary Radar Primary Pulse Radar operates on Bearing by Search light principle and Range by echo principle Pulse Radar transmits and receives the reflected pulses from a target using the same radar antenna Direction of the target is obtained by calculating the direction from where pulse is reflected The time delay for the pulse to go up to the target and return to the radar is converted into range of the target in pulse radar Primary Continuous wave radar transmits and receives its reflected continuous wave transmission Range of…
Microwave Landing System (MLS)
Microwave Landing System Introduction to Microwave Landing System (MLS) MLS is an economical precision landing aid in SHF band frequencies between 5031.0 to 5090.7 MHz with a built in DME Emission designator for MLS is N0X that indicates modulated carrier and data transmission MLS includes Azimuth guidance, Elevation guidance, Distance measuring equipment, Missed approach system and Flare sub systems MLS can be used in hilly terrain due to lack of site errors MLS operates up to 200 channels in SHF band the system is not affected by civilian FM transmissions…