TRACKING WIDGET(TIDGET)

Nithin K Thomas

S7 E&I CEK

Familiarization with GPS

Components:

1. Space Segment2. Control Segment3. User Segment or Receiver

• Space Segment 24 satellites in 6 orbital planes. 30 satellites at present at 11000miles above earth.

• Control Segment Ground stations on earth. Monitors orbiting and performs clock corrections.

• Receiver Navigation and precise positioning. Timing and research projects.

Positioning using Satellites

ADVANCED FORMS OF GPS

Differential GPSusing two ground based receivers.

Carrier-Phase GPScarrier frequency is very high.

Augmented GPSuses one geostationary satellite

Reasons for TIDGET

• For aircrafts, multiple stand alone GPS receivers are required.

• Power, mass and volume.

• Continuous link with satellites during navigation.

TIDGET Architecture

Multiple Antenna Installation for All -

Round Visibility

To achieve high accuracyTo prevent degradation of

GPS signals.

TIDGET Hardware Assembly

• Three identical circuit boards.• One master and two slaves.

Each board consists of :• Connectors:

1. Avionics host connection( power, control and data).

2. GPS antenna connection.3. Stack-thru connection.

• Low-Noise Amplifier.• Integrated GPS front-end.• CPLD with SRAM.• TCXO and Buffers.

Hardware Performance• Snapshot receivedthrough antenna.

• RF to digital base-

band by integrated MASTERGPS front-end. UNIT

• GPS RF circuitrycontrolled by CPLD.

• Snapshot processed by the software.

Software Processing

Working of TIDGET in Brief

• Snapshot from satellite to Antenna.

• Low-Noise Amplifier.

• RF to digital by GPS front-end.

• Snapshot saved in the Buffer.

• Position determination using SDR.

• RF circuitry turned off till next snapshot.

CONCLUSIONThe TIDGET Advantages:

• Average Power Consumption is very low.

• Continuous link with satellite not required.

• Thermal problems avoided (>50ms).

• Multiple snapshots can be stored in queue.

THANK YOU