Abstract: A method and a device of providing timing information within a wireless communication system is described. The timing information is extracted from a received transmit signal. The inventive method comprises the steps of providing a training signal on the receiver side relating to a known signal portion of the transmit signal, scaling the training signal, quantizing the scaled training signal, correlating one or more parts of the received transmit signal with the scaled training signal to obtain one or more correlation results, and determining the timing information on the basis of the correlation results.

Abstract: A method and a device of providing timing information within a wireless communication system is described. The timing information is extracted from a received transmit signal. The inventive method comprises the steps of providing a training signal on the receiver side relating to a known signal portion of the transmit signal, scaling the training signal, quantizing the scaled training signal, correlating one or more parts of the received transmit signal with the scaled training signal to obtain one or more correlation results, and determining the timing information on the basis of the correlation results.

Abstract: A process measurement instrument adapted for wireless communication, comprising a measurement unit (7) arranged to determine a measurement value of a process variable, a memory (21) arranged to store a current measurement value of the process variable, a wireless communication unit (8), arranged to access the current measurement value and communicate the current measurement value over a wireless communication channel according to a protocol with intermittently active communication, and arbitration logic (22), in communication with the measurement unit and the wireless communication unit, and arranged to ensure that active periods of the measurement unit occur when the wireless communication is inactive. The measurement unit and communication unit are thus able to share information via the common memory, e.g. by sequential read/write access. This avoids the need for simultaneous activity.

Abstract: A radar level detector for detecting that a surface of a product in a tank has entered a predefined distance range in an upper half of said tank, said level detector comprising a transmitter for transmitting an electromagnetic transmission signal into the tank, a propagation device for allowing said transmission signal to propagate towards said surface and for returning a reflection of said transmission signal from said surface, a selector for selecting a portion of said reflection, said portion defining said predefined distance range, a detector for setting a discrete signal to an active level if said portion includes information indicating a surface reflection, and an interface for communicating said discrete signal externally of said level detector. As it is not necessary to determine the filling level at every point in time, the signal processing of the detector according to the present invention can be significantly simplified, leading to a more cost efficient product and less power consumption.

Abstract: A method for determining a process variable of a product in a tank based on a time delay of electromagnetic waves. The method further comprises forming a measurement signal comprising a sequence of values, each value representing a time correlation between a pulse of a reference signal and a reflected signal, sampling and digitizing this measurement signal to form a digital signal, identifying a time window of the digital signal including the surface echo peak, determining a relative time period between a reference time corresponding to the predefined reference and a beginning of the time window, time-to-frequency transforming the digital signal in the time window to obtain a phase spectrum, determining a relative phase shift of the spectrum and using the relative phase shift to calculate a corresponding time shift, and determining the time delay by adding the relative time period and the time shift.

Abstract: In a packet transmission system, especially wireless transmission system, where data is transmitted in packets at different error protection levels and where the error protection level of one packet (=the succeeding packet) may differ from the error protection level of a preceding packet without providing code termination between the said preceding and the said succeeding packet the performance may degrade in case a different error protection level is used by the preceding packet and the succeeding packet. The invention proposes in these cases to insert a supplementary packet between the preceding and the succeeding packet whereby the error protection level of the supplementary packet is higher than the lowest error protection level that is used either by the preceding or the succeeding packet.

Abstract: A method and a device of providing timing information within a wireless communication system is described. The timing information is extracted from a received transmit signal. The inventive method comprises the steps of providing a training signal on the receiver side relating to a known signal portion of the transmit signal, scaling the training signal, quantizing the scaled training signal, correlating one or more parts of the received transmit signal with the scaled training signal to obtain one or more correlation results, and determining the timing information on the basis of the correlation results.

Abstract: A radio receiver system (30) comprises a radio receiver (41), a receiver sample clock (60), which is used for sampling a modulated base-band signal; and a timing correction unit (100). The timing correction unit (100) performs, in the frequency domain, a timing drift compensation between a transmitter sample clock (66) and the receiver sample clock (60). In one example context of implementation, the plural modulated radio frequency carriers have been modulated using Orthogonal Frequency Division Multiplexing (OFDM).

Abstract: A method and a device of providing timing information within a wireless communication system is described. The timing information is extracted from a received transmit signal. The inventive method comprises the steps of providing a training signal on the receiver side relating to a known signal portion of the transmit signal, scaling the training signal, quantizing the scaled training signal, correlating one or more parts of the received transmit signal with the scaled training signal to obtain one or more correlation results, and determining the timing information on the basis of the correlation results.

Abstract: In a packet transmission system, especially wireless transmission system, where data is transmitted in packets at different error protection levels and where the error protection level of one packet (=the succeeding packet) may differ from the error protection level of a preceding packet without providing code termination between the said preceding and the said succeeding packet the performance may degrade in case a different error protection level is used by the preceding packet and the succeeding packet. The invention proposes in these cases to insert a supplementary packet between the preceding and the succeeding packet whereby the error protection level of the supplementary packet is higher than the lowest error protection level that is used either by the preceding or the succeeding packet.

Abstract: In a WLAN where an AP and MTs use a duplex airlink having a MAC frame structure to communicate with each other, the AP places wakeup PDUs at different locations in a MAC frame to allow the MTs to conserve energy by maximizing sleep time. In other embodiments, the wakeup PDUs are sequenced by MAC-ID so that a MT can conclusively determine whether remaining wakeup PDUs in a sequence can contain its MAC-ID, and go to sleep early if they cannot. In another embodiment, a wakeup PDU type can indicate to a corresponding MT whether the MT can expect downlink data later in the same MAC frame. In addition, the wakeup PDU type can indicate to the MT that the MAC frame that it should awaken and remain awake to receive downlink data in the future.

Abstract: A radio receiver system (30) comprises a radio receiver (41), a receiver sample clock (60), which is used for sampling a modulated base-band signal; and a timing correction unit (100). The timing correction unit (100) performs, in the frequency domain, a timing drift compensation between a transmitter sample clock (66) and the receiver sample clock (60). In one example context of implementation, the plural modulated radio frequency carriers have been modulated using Orthogonal Frequency Division Multiplexing (OFDM).

Abstract: Device (200; 500) for minimizing the quantization noise in conversion between analogue and digital form of a multi-carrier signal comprising an AC component (VAC) with a particular RMS value (VRMS). The device comprises means (230; 530) for converting between analogue and digital form with a limited number (b) of bits within a quantization range (±VQR), means (215,235,245,255; 520) for minimizing the noise by creating an ideal ratio (VQR/VRMS) between the quantization range and the RMS value of the AC component, and means for reducing unwanted DC components in the signal and centering the signal by the wanted DC components being placed in the centre of the quantization range.