123 results about "Signal quality index" patented technology

A method for restraining inter-cell interference in a mobile communication system is provided. The method uses the fast dynamic selection of the Fractional Frequency Reuse (FFR) technology and the Macro Diversity (MD) technology of the cell edge to increase the cell edge user data rate and provide excellent system capacity. The method is particularly suitable in a OFDMA mobile communication system downlink. The method comprises the steps of: (a) determining whether the cell edge user is able to operate the MD technology; (b) processing the fast dynamic selection of the FFR technology and the MD technology for the cell edge user, and the selection is made based on a instantaneous link Signal Quality Index (SQI); and (c) allocating the center subband or the edge subband to the cell edge user according to the selection.

A method and a device for determining the quality of signal used for measuring a physiological parameter. One embodiment of the present invention is directed towards a pulse oximeter, where the measured physiological parameter includes a patient's pulse rate and blood oxygen saturation. The signal quality, which is indicative of the accuracy and reliability of the measured physiological parameter, is calculated by combining a plurality of signal quality indicators, each of which is an indicator of a quality of the measured signal. The value of the signal quality metric is compared to a threshold and based on this comparison various decisions are made by the medical device. One decision is directed towards deciding whether or not to display the measured physiological parameter, to ensure that only accurate measured values are displayed. Another decision is directed towards providing feedback to guide the clinician to adjust the location of the sensor to a more suitable tissue location.

A test stimulus includes two signals RR, S. Signal S is transmitted to a customer equipment interface and over a system under test to a complementary remote apparatus. The test apparatus has two inputs processed by a number of functional elements. The first input is the reference signal RR. The other input is a corresponding test signal R' generated at remote test apparatus as a test signal R, identical with reference signal RR, and transmitted over the system under test via the customer interface. These two versions of the same test signal are compared. Firstly, the signals RR, R' are processed by a psycho-acoustic model, the output of which is transmitted to a perceptual layer, and then to a conversion unit which also receives a further input from a non-optimum loudness rating unit. The output from the conversion unit is transmitted to a signal quality determination unit, which also receives an input from the customer equipment interface. The non-optimum loudness rating unit processes inputs from the customer equipment interface and signal generator. During an iterative process, the signal generator receives feedback control from the signal quality determination unit. The remote test apparatus similarly receives a modified version of signal S (viz S') from the network and compares it with a locally-generated reference version SR. In an alternative arrangement the same test apparatus is connected to both test points of the network and processes both signals S and R, either serially or in parallel.

A method for determining coverage gaps within a geographical area served by a wireless communication network includes: (a) receiving a location report from each of a plurality of mobile units; (b) storing all location reports received from the mobile units in a database; and (c) searching the database for a position within the geographical area at which an acceptable quality wireless signal has not been received. The location report may include a measured signal quality metric of the wireless link, which may be the signal strength of the wireless link, a bit error rate of the wireless link, or both. Location reports may be displayed on a map to show coverage quality and gaps. Statistical technique and quantitative techniques can be applied on the signal quality metrics reported.

The invention is intended to provide an adaptive rate adjustment method of an LPWAN internet of things based on a network condition. The adaptive rate adjustment method comprises the steps of receiving uplink frames sent by a terminal; sampling SNR and RSSI values of latest N frames; making a statistics of a packet loss rate according to continuity of frame serial numbers; making a statistics of loads erl of SF (Spread Factor) sub-channels according to occupied channels and used SFs of the terminal; weighting to calculate an expected DR (Data Rate) <mote> of the terminal; when the packet lossrate of the terminal exceeds a packet loss threshold value in an ADR (Adaptive Data Rate) strategy, performing packet loss rate adjustment; when the packet loss rate of the terminal does not exceed the packet loss threshold value in the ADR strategy, performing normal rate adjustment; sending an ADR command to the terminal, and enabling the terminal to adjust a data transmission rate according toan own strategy after receiving the ADR command and make a response; and if a LoRaWAN server does not receive the response, considering that the sending is failed, and repeating to send till the response is received. The adaptive rate adjustment method has the following beneficial effects: the adaptive adjustment can be performed on the data rate of the terminal according to an own network condition including conditions such as a signal quality index, a channel load and the packet loss rate.

The present disclosure relates to a system for physiological signal quality assessment, the system includes: a first filter module for implementing a filter process on an inputted first physiological signal; a first periodicity detection module for detecting periodicity of the filtered first physiological signal, and determining periodic segmentation point of the first physiological signal; a feature extracting module for extracting corresponding signal features of the first physiological signal in each heart period; and a fuzzy logic module for building up a fuzzy logic model according to the extracted signal features, and calculating a signal quality index for the first physiological signal in the relative period based on the built fuzzy logic model, and determining a signal attribute according to the signal quality index. A method for physiological signal quality assessment is provided as well. The system and method for physiological signal quality assessment calculate the signal quality index, determine the signal attribute according to the signal quality index, therefore recognize the abnormal signal out of the first physiological signal, and result in high quality physiological signals.

An optical disc apparatus includes a control section. The control section performs a first search while the tracking control is in the off state. The first search is for searching for a plurality of sets of the focus positions of the light beam and the spherical aberration amounts such that an amplitude of the tracking error signal is greater than a predetermined value. The control section performs a second search while the tracking control is in the on state. The second search is for determining a set of the focus position of the light beam and the spherical aberration amount such that the reproduced signal quality index is substantially optimal, among the plurality of sets of the focus positions of the light beam and the spherical aberration amounts obtained in the first search.

In one embodiment, the present invention provide a method for detecting signal quality metrics of a constant modulo (CM) signal received in two different signal paths, and combining the signal from the two signal paths based at least in part on the detected first and second signal quality metrics. Such method may be implemented in a radio receiver such as an automobile receiver.

The invention provides a method for monitoring the signal quality by adopting a multichannel parallel correlation peak sampling mode, and belongs to the field of satellite navigation. The method comprises the following steps of: determining the number of sampling points based on a sampling frequency and the number of channels of a receiver according to an actual monitoring task demand of a user; then detecting a satellite to be monitored by adopting the multichannel parallel correlation peak sampling mode, acquiring correlation peak sampling values, and fitting the acquired correlation peak values; and acquiring a detection statistic of every two symmetric sampling points, and monitoring the correlation peak quality of a signal in real time by adopting a weighted difference method according to the detection statistic of every two symmetric sampling points. Hardware facilities are not required to be changed, and the method is suitable for satellite bands; only aiming at detection of a satellite signal, all channels are set according to the satellite signal; due to a plurality of channels for sampling, the sampling rate is increased because of the advantage that the time is replacedwith the space; furthermore, the quality of the satellite signal is detected, and the cost is saved.

A reproducing apparatus includes a head unit operable to direct a laser light beam onto a recording medium, the head unit having a focus servo mechanism and a spherical aberration correction mechanism for laser light; an evaluation signal generating unit operable to generate an evaluation signal serving as an index of quality of a reproduced signal; a focus servo unit operable to perform a focus servo operation by driving the focus servo mechanism in response to a focus error signal; a spherical aberration correction unit operable to perform spherical aberration correction by driving the spherical aberration correction mechanism in response to a spherical aberration correction value; a focus bias unit operable to add a focus bias to a focus loop containing the focus servo unit; and a control unit operable to control adjustment of a spherical aberration correction value and a focus bias value to be set in the spherical aberration correction unit and the focus bias unit, respectively.

A signal processing system improves signal quality by accurately locating and eliminating a feedback signal in an input signal, such as an audio signal. The signal processing system interpolates between frequency sample points to obtain a more accurate identification of a feedback signal frequency. A less intrusive filter reduces or eliminates the identified frequency signal frequency without excessive adverse effects on adjacent frequencies in the input signal.