Phasemeter core for intersatellite laser heterodyne interferometry: modelling, simulations and experiments

Inter satellite laser interferometry is a central component of future space-borne gravity instruments like LISA, eLISA, NGO and future geodesy missions. The inherently small laser wavelength allows to measure distance variations with extremely high precision by interfering a reference beam with a measurement beam. The readout of such interferometers is often based on tracking phasemeters, able to measure the phase of an incoming beatnote with high precision over a wide range of frequencies. The implementation of such phasemeters is based on all digital phase-locked loops, hosted in FPGAs. Here we present a precise model of an all digital phase locked loop that allows to design such a readout algorithm and we support our analysis by numerical performance measurements and experiments with analog signals.Comment: 17 pages, 6 figures, accepted for publication in CQ

Optical ranging and data transfer development for LISA

In order to implement optical inter-spacecraft ranging and data transfer for LISA, the carrier of the laser link must be phase modulated with pseudo-randon noise sidebands. The data acquisition and delay estimation are then implemented in the phasemeter as back end processing. This work presents a proposed demodulation scheme with submeter ranging accuracy and several kilobytes data rate. Its functionality is demonstrated both in a software simulation and in a FPGA-based hardware implementation

LISA phasemeter development: Advanced prototyping

We present the status of our investigations on the LISA Phasemeter. The new prototype is based on a custom-designed breadboard with four high-speed ADC and two DAC channels, extended readout capabilities and a large FPGA (field programmable gate array). The required main functionalities and performance of the prototype have been demonstrated in laboratory conditions. © 2009 IOP Publishing Ltd

Ranging and phase measurement for LISA

The LISA phase measurement system (PMS) will provide interferometric phase readout of the primary heterodyne signal at microcycle sensitivity, ranging measurements at sub-meter accuracy and data communication at rates of several kilobits per seconds. Our investigations are focused on inter-spacecraft laser ranging and data transfer for LISA using Direct Sequence Spread Spectrum (DS/SS) modulation onto the laser links. We present the setup of an optical experimental to test the levels of performance achievable with a single laser link as well as a new hardware prototype based on FPGA (Field Programmable Gate Array) processing to perform high-accuracy phase readout of the optical signal, ranging measurements, data communication and is suitable for clock noise demodulation and digital laser-phase locking

Status of the eLISA on table (LOT) electro-optical simulator for space based, long arms interferometers

International audienc

HSE performance report on NSP 2011. June 2011.

The Performance Report (PR) provides an overall analysis of key performance data from Finance, HR, Hospital and Primary & Community Services. The activity data reported is based on Performance Activity and Key Performance Indicators outlined in the NSP 2011. The June Performance Report is the second quarterly update for 2011 and includes additional metrics as outlined in the National Service Plan 2011. The PR is used by the Performance Monitoring & Control committee (PMCC), the CEO and the HSE Board to monitor performance against planned activity, as outlined in the NSP, and to highlight areas for improvement. The PR also provides an update to the DoHC on the delivery of the NSP. A Supplementary Report is also produced each month which provides more detailed data on the metrics covered in the Performance Report. This will be expanded quarterly and biannually to report on progress against the Deliverables outlined in NSP 2011. The Supplementary report contains information on Methadone treatment activity and expenditure

NGO assessment study report (Yellow Book)

http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=49839#The NGO (New Gravitational wave Observatory) concept results from the reformulation of the LISA mission into a European-led mission. This report, the so-called Yellow Book, contains the results of ESA's assessment study (Phase 0/A) of the candidate L-class Cosmic Vision mission NGO