Abstract: A method and system for detecting and ranging targets within a scene are provided. The method can include emitting an emission signal onto the scene and receiving a return signal including echoes produced by reflection of the emission signal from the targets. The method can also include digitizing the return signal into a digital signal waveform including N real-valued samples representing the return signal at N sequential sampling times. The method can further include creating, from the digital signal waveform, an N×N second-order signal matrix having a main diagonal whose nth element is expressed in terms of the square of the nth sample of the digital signal waveform. The method can also include deriving, based on the signal matrix, time-of-flight information associated with the echoes and indicative of range information associated with the targets. The method and system can be used, for example, in lidar-based remote sensing applications.

Abstract: A method and system for detecting and ranging targets within a scene are provided. The method can include emitting an emission signal onto the scene and receiving a return signal including echoes produced by reflection of the emission signal from the targets. The method can also include digitizing the return signal into a digital signal waveform including N real-valued samples representing the return signal at N sequential sampling times. The method can further include creating, from the digital signal waveform, an N×N second-order signal matrix having a main diagonal whose nth element is expressed in terms of the square of the nth sample of the digital signal waveform. The method can also include deriving, based on the signal matrix, time-of-flight information associated with the echoes and indicative of range information associated with the targets. The method and system can be used, for example, in lidar-based remote sensing applications.

Abstract: A system and method of replicating database records for use in resource constrained wireless computing devices. The replication method has a low processing burden and is well suited to low-bandwidth, unreliable connections found in many wireless networks. To reduce the amount of memory used on the wireless device only a change log record is time-stamped, not every database record. The change log defines what data is to be replicated and needs to sent to a main server that hosts a master copy of the database. The change log is made compact to reduce the amount of data that needs to be sent for data replication by only requiring the field that has changed in a record and a timestamp to be sent, not the entire record in which the change was made.

Abstract: Content is automatically provided to a mobile web browsing device from a web server, by the following process: (a) receiving at a computer, remotely connected to the device over a wireless network, a log of data identifying content that has been viewed by the device; (b) automatically sending updated content stored on the web server to the device over the wireless network; (c) causing that updated content to be automatically stored in device memory. Because user activity is replicated back from the device to the remote computer, the content cached on a given device can be completely optimised for the user of that device and no-one else.

Abstract: Where a first computing device is given responsibility for determining whether data that is time stamped by a second computing device is replicated or not, then the first device can compare a time stamp from the second device against a time signal from its own internal clock to determine a delta and use that delta to deduce the correct delta to apply to time stamps associated with later data from the second computing device.

Abstract: Resource constrained wireless computing devices (e.g. mobile telephones) are given a replication capability for database records (e.g. to enable backing up contacts, e-mails, photographs etc. onto a remote server). This operates without undue processing burden, using low bandwidth unreliable wireless connections. This is achieved by not including a time stamp in each database record, but instead time stamping only a change log record; this approach saves considerable memory space on the wireless device since there is no need to time stamp every database record, as is usually done in the prior art. The change log defines what data is to be replicated; it alone has to be sent to a main server which hosts a master copy of the database and hence has to be kept up to date. Because the change log is compact, far less data has to be sent for data replication purposes—typically only the field which has changed, how it was be changed and when it was changed on the wireless computing device.