Upper Air Sounding Systems

Transcription

1 Upper Air Sounding Systems Sounding the Future

2 Content Welcome to GRAW Radiosondes 03 Radiosonde DFM Groundstation GS-E for Office Use 06 Groundstation GS-H with Handheld Receiver 07 Antenna Sets 08 Software GRAWMET 10 Ozone - Sounding 12 Accessories 13 Our Company History 14

3 Welcome to GRAW Radiosondes GRAW Radiosondes is a well-established German company which has developed and manufactured Upper Air Sounding Systems since Our customers are military, academic research, and meteorological institutions worldwide. Today GRAW Radiosondes is a member of the NORIS Group which is a family owned business focused on measurement technologies. We have access to more than 250 professionals worldwide but still benefit from the flexibility and quick decision of a family owned business. GRAW Radiosondes is located at the headquarters of NORIS Group in Nuremberg, Germany. We would like to extend a very warm welcome to GRAW Radiosondes! Michael Schmidmer Florian Schmidmer 03

4 Radiosonde DFM-09 Extremely Low Weight GRAW s latest state-of-the-art radiosonde, the DFM-09, is currently the smallest and lightest synoptic radiosonde available on the market today. The DFM-09 has dimensions of 200 mm x 42 mm x 60 mm and weighs just 90 grams (Ready to Fly)! The DFM-09 has already proven itself to many customers worldwide - delivering excellent performance, ease of use, and high reliability. Sensor Boom All sensors are delivered Ready to Fly % factory calibrated and with no additional ground calibration necessary prior to launch The temperature and humidity sensor boom ensures precise measurements during ascent, it is unaffected by any thermal influences of the sondes housing A mirrored surface reduces errors due to solar radiation A ceramic temperature sensor delivers a fast response due to its low mass and low thermal capacity Fast, capacitive polymer humidity sensor Function and Design The DFM-09 radiosonde is designed to reliably measure the atmospheric profile of pressure, temperature, humidity, wind speed, and wind direction from the surface to an altitude of 40 kms. Continuous data sets are sent to the groundstation by a high quality radio-telemetry link. High-Power Lithium Battery Shelf storage life of several years Simple activation, just a small on/off switch No special preparation Environmentally friendly Fulfills all transportation and storage regulations Differential C/A-Code GPS for Wind Finding The GRAW radiosonde family has a standard on-board C/A code-correlated GPS receiver. The sonde s positional information is transmitted to the groundstation where it is corrected with the groundstation s differential GPS system. The resulting data is used to accurately calculate the wind speed and direction of the sonde s ascent - at all heights. Fully coded GPS allows the groundstation to be used on the move, such as launching from a vehicle or from a ship. High Quality Telemetry Each sonde contains a high specification telemetry transmitter. The radio transmission from the sonde meets demanding radio requirements and can cope with long slant ranges, even as far as 300 km. The use of code-spreading, a method where link-errors can be readily detected and corrected and other modern digital radio techniques such as interleaving which minimises the effect of burst errors, ensures that the data is reliably received at the distant groundstation. The continuous on-board measurements of all sensors and transmission of their data is performed in a time-window of less than one second. 04

5 Additionally, in a spare channel, diagnostic information from the sonde s on-board Built In Test (BIT) systems are transmitted, thus ensuring the data sent is reliable during the ascent. Microprocessor Controlled All important functions of the radiosonde are controlled by an on-board, low power microprocessor. The microprocessor controls the radiosonde initilisation, sensor measurements, communication, and in flight data quality control. Freely Programmable Frequency Each radiosonde can transmit in a narrow channel anywhere within the meteorological band (400 to 406 MHz). The sonde uses an on-board frequency synthesiser, which is automatically set to the desired transmission channel during initialisation. The highly-sensitive groundstation receiver system does not require a steered antenna and can receive valid data from sondes up to 300 km slant range using its compact dual antenna set. Radiosonde DFM-09 Weight < 90 g, ready to start Size 200 mm x 42 mm x 60 mm Battery Dry Lithium Activation Switch Wind finding Differential GPS (20 channels) Transmission-rate One full data set per second Bandwith < 20 khz Frequency deviation +/- 3 khz Modulation FSK Error correction telemetry Code-spreading, interleaving Temperature resolution 0.1 C Temperature accuracy < 0.2 C Humidity resolution 1 % rh Humidity accuracy < 5 % rh Pressure accuracy < 0.3 hpa Geopotential height accuracy < 10 m Wind speed accuracy < 0.2 m/s Accuracy horizontal position < 5 m Quick and Easy Initialisation Prior to launch, a simple cable connection starts up the sonde, sets its frequency and downloads the calibration data for the sensors from its on-board non-volatile memory. During this rapid and simple initialisation phase, the sonde is also checked and tested by the groundstation. The sonde is now ready for immediate release. 05

6 Groundstation GS-E for Office Use Components PWD PWA ANT.1 ANT.2 GPS 400 MHz receiver integrated Initialisation cable between GS-E or PC and radiosonde Overview The main function of the GS-E groundstation is receiving the radiosonde signal Groundstation GS-E and providing local GPS information. All functions of the GS-E are software-controlled by a standard PC via USB. SDR (Software Defined Receiver) The core of the GS-E is a so-called software defined receiver. A Software Defined Receiver (SDR) is such where demodulation RECEIVER Type DDS-based dual-conversion superheterodyne with software-defined last IF stage and demodulator Frequency range 400 MHz MHz Tuning steps 20 khz GPS Channels 20 CONNECTIONS 400 MHz antenna 2 GPS antenna 1 GPS repeater 1 USB connection to PC 1 USB connection to radiosonde 1 PC REQUIREMENTS Operating system Windows XP/Vista/Windows 7 Interface USB POWER SUPPLY AC 100 V/AC to 240 V/AC DC 10 V/DC to 30 V/DC DIMENSIONS Size 320 mm x 190 mm x 90 mm Weight 3300 g and the last IF (intermediate frequency) processing are done entirely in software. Usually this means using a DSP, but in the case of the GS-E, this processing is done on a PC. Most modern PCs are now faster and more powerful than many DSPs were only a few years ago. The radiosonde signal is received by a software-defined PC-based narrowband receiver (400 MHz to 406 MHz). This PCbased receiver is USB-controlled and compatible with modern desktop and notebook computers with USB interface. Antenna Switch (Diversity) The GS-E provides a USB controlled antenna switch. This gives the possibility to connect two 400 MHz antennas at the same time to ensure 100 % coverage. The selection of the right antenna is done completely automatically by the software GRAWMET by continuously checking the signal strength of both inputs. GPS Module An integrated GPS module provides exact position information of the groundstation. This GPS information can be used for applying differential GPS mode. Software The GS-E is fully controlled by the meteorological software GRAWMET via USB. This includes the tuning of the receiving frequency, control of AFC (Automatic Frequency Control), selecting of the optimal filters, frequency sweeping, selection of the right antenna, etc. 06

7 Groundstation GS-H with Handheld Receiver Groundstation GS-H PC Handheld receiver Handheld size Handheld weight Standard notebook (e. g. existing customer notebook) Tuneable between 400 MHz and 406 MHz 58 mm x 86 mm x 27 mm 185 g Components Optional with standard notebook with USB-interface and soundcard Handheld 400 MHz receiver with integrated antenna Initialisation cable between notebook and radiosonde Overview The GS-H groundstation is a highly portable system. It is well suited to use by universities and research establishments that do not prefer fixed antennas and which require limited soundings on a project by project basis. The complete ground-system consists of a standard notebook and the GS-H with integrated 400 MHz antenna, all powered by batteries. BAND LOCK TS SET AM MODE SCAN V/M S.MW SKIP 07

8 Antenna Sets Different antenna configurations are available for the GS-E groundstation: 1. Omnidirectional Antenna The omnidirectional antenna is the perfect solution for most climactic situations as it guarantees full receiving coverage of the radiosonde signal except for a small gap directly overhead in high altitudes. Under normal climactic situations, the omnidirectional antenna is 100 % sufficient for reliable soundings. As a standard, the omnidirectional antenna comes with a low noise amplifier and a 40 m antenna cable. Other lengths are available on request Omnidirectional Antenna Type Dipole antenna Bandwidth MHz Gain 3.5 dbi Height 71 cm Weight 1.9 kg Overhead Antenna The overhead antenna complements the omnidirectional antenna and is useful for special climatic situations. It closes the receiving gap of the omnidirectional antenna directly overhead in high altitudes. As a standard, the overhead antenna comes with a low noise amplifier and a 40 m antenna cable. Other lengths are available on request. Overhead Antenna Type Helical antenna Bandwidth MHz Gain 3.5 dbi Height 50 cm Weight 2.6 kg 08

9 3. GPS Antenna The local GPS antenna facilitates the prestart preparation as it enables the user to check the GPS functionality of the radiosonde in-house before start. Also, the co- GPS Antenna Type Centre frequency Weight Helical antenna MHz 0.2 kg 4. Tripods For mobile applications, all antenna can be mounted on a tripod. Depending on the used antenna, different versions of tripods are available. ordinates of the groundstation are made available automatically. The local GPS antenna always comes together with an indoor GPS repeater. 09

10 Software GRAWMET Software Features GRAWMET is the meteorological software system for all GRAW-groundstations based on Windows XP, Vista or Windows 7. The main functions of GRAWMET are the initialisation of the radiosonde for launch and the evaluation and display of radiosonde data during the ascent. The system generates WMO and STAN- AG weather messages as well as various graphical and tabulated evaluations. The software uses the common windows style graphical user interface (GUI) making it easy to work with. Data from the radiosonde is received by the groundstation for further processing by GRAWMET. Automatic Launch Recognition The actual time of the balloon launch is automatically recognised by the system. Launch time computation is through linear regression. As soon as a defined number of valid measured values have been received, the measured values are acknowledged and then stored as valid ascent data. Quality Control of Data All data is checked for any measured values that deviate from predetermined tolerance limits. Any measured values outside these limits will not be processed while an ascent is in progress. Any discrepancies found are entered into the log file and displayed on the screen. Incoming data is also compared with a predetermined expectancy window. Data is passed through a track filter for the elimiation of any errors in the run of measured values. Software Adaptation to User Needs The program offers a host of variable setting possibilities of the software and thus can be closely matched to user s needs. It is possible amongst other things to modify various parameters, such as units of measurement or the number of the measured value curves shown in the graphic display. Automatic Frequency Setting During initialisation, it might be necessary to change the transmitting frequency for the ascent. All measured data are transmitted to the groundstation on this frequency. Setting of the frequency is provided by the software. Status Tree This field shows the current data of the radiosonde ascent. It is subdivided into four areas. The sounding data area shows the actual basic data, the current balloon ascent rate and the flight time. In the probe/receiver area information on the radiosonde and the receiver are displayed: channel of the radiosonde and the receiver, receiving level, number of probe, etc. The GPS area visualises the altitude, latitude, longitude and the number of satellites. The last field shows information on the status of the weather messages. Processing and Display of Measured Data Processing of measured data is done by means of data reduction methods. All measured data are checked and stored in the form of time profiles. These time profiles are the basis for generating the weather messages. Display on the screen is in the form of tables or graphic evaluations. Automatic Creation of Weather Messages The program computes and automatically generates standardised current weather messages upon reaching the specific altitude limit. Optionally, the user can change the altitude limits. Provisional computation of weather messages before the set altitude limits are reached is also possible. For greater clarity, all messages computed are presented in the status tree. Generated Messages (Extract) WMO weather messages: PILOT, TEMP, CLIMAT, BUFR, CREX Reports according to FM35 TEMP, FM36 TEMP SHIP or FM38 TEMP MOBIL can be coded optionally Other messages are available on request These weather messages are displayed on the screen in tabulated form and can be filed for future reference. During the ascent, all data of the weather message can be viewed by scrolling. The message headings and body of the message can be later edited in order to supplement messages, if incomplete. 10

11 Weather Indices GRAWMET creates the following weather indices automatically: LFC, LCL, CCL, Showalter Index, CAPE, CINH, EL-Equilibrium Level, K-Index, Total Index, KO Index. Graphic Data Processing Various parameters can be displayed and printed in the form of different graphical presentations: Thermodynamic Diagram, Tephigram, T- Log (P) Diagram, Emagram, Hodograph, Altitude Diagram, Refractive Index, etc. Wind Data Determination To calculate wind parameters, the software uses GPS data provided by the radiosonde. Wind speed and wind direction values are calculated by the changes in the GPS position and GPS velocity vectors of the radiosonde. The DFM-09 is equipped with the latest state of the art GPS modules being capable of receiving 20 satellites at the same time. Data Saving The program saves all data and messages in a database and in a simulation file based on XML. This permits later data transmission or simulation of the flight. Data Transmission and Outputting All weather messages can be output by means of a printer, via an interface to a receiver or disseminated via other data interfaces, such as Firewire, Ethernet, USB or modem. Network Support The system can be operated from multiple groundstations at the same time. Flights can be monitored in realtime from any remote station by simply setting up an internet connection to the main groundstation. Log File All operator inputs as well as alarm messages are automatically saved in a log file. Indication is in the form of a live display. A scroll function permits paging up and down in the log file. Free Demo of Software On request, a free demo version of the software is available for training purposes and for off-line evaluations of prior ascents. Multiple Languages The system is designed as a multiple language system. Apart from the main languages (English, German, French, Spanish), several other languages are available. Please contact us! Google-Earth Support The flight-path of the radiosonde can also be monitored by Google-Earth. 11

12 Ozone - Sounding GRAW Ozone-sonde The GRAW ozone-sonde consists of the scientific radiosonde model DFM-97 in conjunction with the ECC ozone-sensor. The current output of the ECC sensor is directly connected to one of the free inputs of the DFM-97. An additional external temperature sensor is integrated to measure the air temperature in the ozone-channel of the ECC-sensor. In total, 10 inputs are available on the DFM-97 radiosonde for the use of any external sensors. 12

13 Accessories Balloon Filling Unit SO-2 This unit facilitates the filling and preparation of the balloons: The neck of the balloon is put over the nozzle of the SO-2 which is connected to a gas (helium or hydrogen) cylinder or storage tank. Weights are put on the arms of the SO-2 depending on the requested free lift. The filling of the balloon is automatically stopped once the desired free lift is reached and the balloon may then be tied to the radiosonde. The SO-2 can be used for balloons 200 grams and larger. For smaller balloons other suitable units are available. Unwinder UW1 The unwinder (dereeler) UW1 is manufactured of stainless steel and designed for heavier payloads and very constant unwinding speeds. Its own weight is about 70 grams and the cord is available in different lengths. This unwinder is mainly used for scientific applications or heavy payloads. Unwinder UW2 The unwinder (dereeler) UW2 is designed to facilitate the launching of lightweight radiosondes (such as the DFM-09 and DFM-06) under all weather conditions. The UW2 is connected between the radiosonde and the balloon by a cord which slowly increases its length after release of the balloon. The unwinding speed of the cord is controlled by a small rubber balloon which acts as a brake. Unwinder UW1 Unwinder UW2 Cord length 30 m (other lengths on request) 30 m (other lengths on request) Maximum payload 5 kg 600 g Unwinding speed 0.1 m/s (payload 200 g) 0.3 m/s (payload 2.5 kg) 0.5 m/s (payload 200 g) 1.5 m/s (payload 600 g) Weight 70 g 30 g 13

14 Our Company History 1938 Founding of the company Dr. Graw Messgeräte in Berlin/Germany by the physicist Dr. Graw 1942 Dr. Graw developed the heart of the radiosondes, the GRAW morse encoding cylinder 1948 Relocation of the company to Nuremberg/Germany 1976 Mr. Horst Schmidmer (former owner of NORIS Group) takes over all shares of Dr. Graw 1990 Development of the first purely digital radiosonde DFM Development of the first real fully coded differential GPS-radiosonde DFM-90 DGPS

15 1998 Development of the optimized DFM-97 GPS-radiosonde 2004 Start of the development of the GPS-radiosonde DFM Renaming to GRAW Radiosondes GmbH & Co. KG 2006 Market launch of the DFM-06 radiosonde 2010 Market launch of the DFM-09 radiosonde

16 GRAW Radiosondes GmbH & Co. KG Muggenhofer Strasse Nuremberg Germany PR-GRS en V / Errors and omissions excepted. Tel.: Fax: info@graw.de