Mid-Sea and Land Based Wind Measurement for Technology Demonstrator Table 1. which are essential when simultaneous ascents are to be conducted as per launch requirements. The specifications of Pisharoty sonde ground station are given in Table 1. Specifications of Pisharoty Sonde System Sonde Item Temperature Pressure Relative humidity Wind velocity Antenna Battery Parameter Value Range À90 to 60 C Resolution 1.0 C Accuracy Æ1 C Response time <1 s Range 0-1031 mBar Resolution 0.1 mBar Accuracy Æ1.4 mBar Range 0%-100% Resolution 0.1% Accuracy Æ5% Response time <5 s Range 0-500 m/s Resolution 0.01 m/s Accuracy 0.1 m/s Type Quarter wave monopole Frequency 403 MHz Band width Æ 4 MHz Beam width 80 Gain -3.5 dBi Polarization Linear VSWR <1.5 Operating time 4 hours Frequency 400-406 MHz Power 50 mW Ground station Carrier Modulation Supply Antenna-monopole Antenna- quadrifilar helix 34 Carrier frequency 400-406 MHz programmable in steps of 125 kHz Power Minimum þ15 dBm Spurious Rejection > 45 dBc Scheme Biphase-L / Guassian FSK Output data rate 768 bps Æ 5% Frequency Deviation Æ 5 kHz Mains $230-220 V AC 50 Hz Battery backup 8 hours Frequency 403 MHz Band width Æ 4 MHz Gain 2 dBi Polarization Linear VSWR <1.5 Frequency 403 MHz Band width Æ 4 MHz Gain 4 dBi Polarization RCP VSWR <1.5 IEEE A&E SYSTEMS MAGAZINE WIND PROFILE GENERATION RLV-TD HEX 01 mission had the requirement of both ascent and descent phase wind profiles. Ascent phase wind profile was generated from wind measurements conducted at SDSC SHAR and descent phase wind profile was generated from ship-based measurements from the Bay of Bengal. The ascent phase DOL WB of launch vehicles requires the latest continuous wind profile from the ground to 50-km altitude over the launch station. This profile contains wind data at 300-m interval up to 21 km and at 1-km interval thereafter. Generally, the balloons used ascent up to an altitude of approximately 36 km. To get the latest wind profile, four-time staggered sonde ascents, referred as L1-L4, are conducted at 20 minutes interval. After 20 minutes of L4 ascent, data from all the four ascents are processed and merged to generate a single profile with the latest wind data at different altitudes up to maximum attained height. Further data up to 40 km is taken from the high altitude balloon (HAB) ascents with Pisharoty sonde, conducted on the previous days of launch. A total of 40-60 km wind is taken from available chaff data collected using sounding rockets. The profile generation scheme is represented in Figure 7. Additional three ascents are conducted to take care of the full launch window period, depending upon the mission requirement. Suitable backup plan is also worked out and implemented. The data received at ground station are collected by two sets of receivers for full redundancy (prime and redundant). The schematic of Pisharoty sonde system configuration at SDSC SHAR for ascent phase wind profile generation is shown in Figure 8. RLV-TD HEX 01 guidance design during descent phase is based on INS estimated air-data parameters up to an altitude MARCH 2019