公开(公告)号：US20230176232A1

公开(公告)日：2023-06-08

申请号：US17921054

申请日：2021-05-07

Applicant: QINETIQ LIMITED

Inventor： Malcolm David MACLEOD

IPC: G01S19/24 ,  G01S19/30 ,  G01S19/37 ,  H03M13/23 ,  H03M13/00

CPC classification number: G01S19/243 ,  G01S19/30 ,  G01S19/37 ,  H03M13/235 ,  H03M13/611

Abstract: A non-systematic convolutional decoder of a convolutionally encoded multi-level data stream includes a shift register and two or more paths of exclusive-OR (XOR) gates, arranged to reconstruct an original input information stream, each path having a quantiser arranged to quantise the signal to two levels, and a set of XOR gates arranged to match an encoding path in an associated convolutional encoder, and a selector arranged to feed an output from each path to a single input of the shift register. If the paths have differing values at their output, the selector may choose the value from the path based upon a function of the multi-level signals associated with each path, such as the path with the largest absolute signal level. The decoder provides a simple means for decoding signals while allowing the signal to also or instead be decoded using e.g. a Viterbi decoder if higher performance is required.

公开(公告)号：US20190268036A1

公开(公告)日：2019-08-29

申请号：US16318423

申请日：2017-07-27

Applicant: QINETIQ LIMITED

Inventor： Malcolm David MACLEOD

IPC: H04B1/7075 ,  G01S19/29 ,  G01S19/30 ,  H04B1/7136

Abstract: A method for the reception of a frequency hopped direct sequence spread spectrum signal includes acquiring the signal by splitting the received signal into a plurality of processing sub-channels, each corresponding to one or more hop frequencies; and within each sub-channel: i) subtracting any sub-carrier frequency from the received signal; ii) filtering the signal from (i) using a chip-matched filter; iii) selecting a sub-set of samples from the filtered signal; iv) correlating the sampled signal from step (iii) with a known reference signal to produce at least one correlator output. The output(s) from each sub-channel are provided to an input of a corresponding one or more common discrete time Fourier transforms (DTFT), and an output therefrom having a peak above a predetermined threshold is selected for further processing in the receiver. The method is a less expensive way of tracking the signal and can demodulate appropriately modulated signals.

公开(公告)号：US20190195994A1

公开(公告)日：2019-06-27

申请号：US16099084

申请日：2017-05-04

Applicant: QINETIQ LIMITED

Inventor： David Arthur ORCHARD ,  Peter David KIGHTLEY ,  Malcolm David MACLEOD

IPC: G01S7/497 ,  G01S17/36 ,  G01S7/491 ,  G01S17/88

CPC classification number: G01S7/497 ,  G01S7/4915 ,  G01S17/36 ,  G01S17/88

Abstract: A system for compensating for phase noise, with particular application in lidar, includes a compensation interferometer that receives a signal from a source, and splits it into a first and second path, with a path length difference Δτ between them. Typically the path length is significantly less than that of the return distance to a target. The output of the compensation interferometer, which consists of phase noise generated in time Δτ is vectorially summed during a time similar to a signal flight time to a target, and the result used to reduce phase noise present on measurements of a target. It further includes means for selecting Δτ such that competing noise elements are reduced or optimised.

公开(公告)号：US20160343252A1

公开(公告)日：2016-11-24

申请号：US15112950

申请日：2015-01-21

Applicant: QINETIQ LIMITED

Inventor： Nigel Clement DAVIES ,  Malcolm David MACLEOD

IPC: G08G1/017 ,  G01S19/21 ,  G06K9/00 ,  G06F17/30 ,  G06T7/20 ,  G06T7/00 ,  H04N7/18 ,  B60R25/33 ,  G06K9/46

CPC classification number: G08G1/0175 ,  B60R25/1025 ,  B60R25/305 ,  B60R25/33 ,  G01S5/06 ,  G01S19/21 ,  G01S19/215 ,  G06F17/30253 ,  G06F17/30268 ,  G06K9/00785 ,  G06K9/46 ,  G06K2209/15 ,  G06T7/20 ,  G06T7/73 ,  G06T2207/30252 ,  H04N7/188

Abstract: A method of identifying a vehicle-borne transmitter emitting an interfering signal over a predefined frequency band. The method comprises monitoring the predefined frequency band at a first location to identify an emission of an interfering signal from a passing vehicle. If an interfering signal is detected, the method further comprises capturing a first image of the passing vehicle to enable an identity of the passing vehicle to be determined.

Abstract translation: 一种识别在预定频带上发射干扰信号的车载发射机的方法。 该方法包括在第一位置监测预定义的频带以识别来自经过的车辆的干扰信号的发射。 如果检测到干扰信号，则所述方法还包括捕获所述经过的车辆的第一图像以使得能够确定所述经过的车辆的身份。

公开(公告)号：US20210242899A1

公开(公告)日：2021-08-05

申请号：US17052219

申请日：2019-06-04

Applicant: QINETIQ LIMITED

Inventor： Malcolm David MACLEOD

IPC: H04B1/7085 ,  G01S19/30 ,  G01S19/24

Abstract: A radio receiver includes a downconverter for downconverting dual sideband signals such as Binary Offset Carrier (BOC) signals from multiple sources to produce an upper and a lower sideband signal, and chip-matched filters for filtering each of the sideband signals. The output of each filter is provided to a series of separate channels, one for each source, where there are at least Early, Prompt and Late gates. Each gate has a nearest-neighbour sampler and a multiplier for multiplying with an appropriate part of a spreading code, a mixer for removing Doppler or other frequency offsets and an integrator. The invention provides a means for demodulating signals such as BOC modulated satellite navigation signals in an efficient manner by using a single downconverter for the received signals of interest from the multiple sources.

公开(公告)号：US20170003397A1

公开(公告)日：2017-01-05

申请号：US15112686

申请日：2015-01-26

Applicant: QINETIQ LIMITED

Inventor： Malcolm David MACLEOD

IPC: G01S19/30

Abstract: The invention relates to a method of determining the time of arrival of an incoming satellite signal at a receiver, the method comprising: receiving an incoming signal, multiplying of the incoming signal by a first real-valued periodic modifying signal to produce a first modified output, correlating the first modified output to obtain a first correlation output, multiplying the incoming signal by a second real-valued periodic modifying signal to produce a second modified output, correlating the second modified output to produce a second correlation output and comparing the first correlation output with the second correlation output.

Abstract translation: 本发明涉及一种确定进入卫星信号到达接收机的时间的方法，该方法包括：接收输入信号，将输入信号乘以第一实值周期性修改信号以产生第一修改输出 将所述第一修改输出相关以获得第一相关输出，将所述输入信号乘以第二实值周期修改信号以产生第二修改输出，将所述第二修改输出相关联以产生第二相关输出，并将所述第一相关输出 具有第二相关输出。