Abstract: A coherent laser radar or lidar device (2;20;84;90) for measuring wind speed is described that comprises a transmitter for transmitting a beam of light to a remote probe volume (6;54), a receiver for detecting back-scattered light and an analyzer for calculating wind velocity at the remote probe volume from the Doppler shift in frequency of the detected back-scattered light. The analyzer is arranged to monitor for the presence of, and/or to ensure the calculated wind speed is corrected for, any Doppler frequency components of the detected back-scattered light that arise from back-scatter off cloud located at a range greater than the range of the remote probe volume. It is described how the lidar (2;20;84;90) may be scanned and wind velocity components calculated by fitting the scanned line of sight velocity values to a predetermined function. Furthermore, it is outlined how an initial fit may be performed to determine which points are to be used in this calculation.

Abstract: Solar energy is converted into electricity by use of a solar concentrator system, a steam production system, a turbine and an alternator. A boiler is heated by a concentrator dish aimed at the sun. The dish may also be fitted with a polar mount, an actuator and a devise for sensing the relative position of the sun. There is a mast on the dish upon which a boiler is mounted which is heated by the sun's concentrated rays. The boiler will preferably be arranged to heat and vaporize water to create continuous steam that is delivered to turn the turbine which is operatively connected to the alternator and from which electricity is generated.

Abstract: Methods and apparatus that implement a transmitter unit and a control unit to alert a user if the control unit is beyond a limited range of communications. A method of alerting a user that a transmitter unit is beyond a limited range of communicating wirelessly with a control unit may include, wirelessly transmitting a radio frequency signal from the transmitter unit to the control unit, determining at the control unit whether the transmitter unit is beyond the limited range of wireless communications, and selectively generating an alert at the control unit based on a result of the determination. Determining at the control unit whether the transmitter unit is beyond the limited range of wireless communications may include detecting an occurrence of a predetermined condition.

Abstract: An apparatus for producing a digital depiction of a signal (10) which is adaptive to the signal itself. A constant rate sampling means, such as an analogue to digital converter (2), samples the signal (10) at a constant rate and produces a first digital depiction (12) of a signal. A transformation means (14) is responsive to the first digital depiction (12) and produces a second digital depiction based on the evolution of the signal. The transformation means may be capable of determining when a predetermined threshold level has been crossed and measuring the time interval between predetermined threshold level crossings. The transformation means (14) may include a logic arrangement and a timer counter and is run from a clock signal (16) from the same clock (6) as drives the sampling means. A method of adapting a conventional ADC (2) to adaptively sample the signal (10) by adding a transformation means (14) run off the same clock (6) as the ADC (2) is also provided.