Multi-Path GNSS Receiver Dramatically Improves Accuracy in Complex Environments

first_imgFURUNO plans to begin sales of the new GF-88 series time synchronization GNSS receivers incorporating this new technology in April of 2019, and to deploy it widely in fields such as 4G/5G mobile base stations, financial trading, power grids, and data centers.As with earlier systems, the GF-88 will support GPS, GLONASS and the Quasi-Zenith Satellite System (QZSS), and also Galileo satellites. It also supports simultaneous reception from four QZSS satellites including a geostationary satellite Michibiki-3. They expect that supporting multi-GNSS will increase the total number of navigation satellites that can be used. Thus, more satellites will be visible in environments with restricted open sky, greatly increasing the effectiveness of our technology to exclude un-needed signals from non-visible satellites, and realize highly-accurate time synchronization. The GF-88 series also includes a model that implements high holdover performance using a precision crystal oscillator, so that it can maintain high time precision even when the satellite signal cannot be received temporarily due to jamming or other interfering signals. This can be applied to applications requiring high reliability, such as 5G mobile base stations, or applications in finance or power grids.NTT is also continuing research to further expand application areas for GNSS. To compute the four parameters for position and time from navigation satellite signals, signals from at least four satellites must be received, but it is not always possible to receive four or more signals from visible satellites in so-called “urban-canyon” environments obstructed by surrounding buildings. In this study, they have conceived a new satellite selection algorithm in which satellite signals suitable for improving the time accuracy are selected in an iterative selection process based on the estimated reception location and the signal arrival times.This algorithm first selects the signals from visible navigation satellites, and if there are fewer than four, it also selects the minimal number of signals with the smallest propagation delay from non-visible satellites. Thus, in poor reception environments, accuracy is improved by aggressively pruning unsuitable satellite signals. This could be called a “select few” satellite selection method. NTT developed a prototype, with this algorithm incorporated into the GF-87 time-synchronization GNSS receiver from FURUNO, and evaluated its performance in a test environment with multi-path reception. They were able to demonstrate accurate time synchronization with time error of approximately one fifth that of earlier devices.Since this method is able to select the best satellite signals regardless of the number of visible satellites in the environment, antennas can be installed with less attention to the location, and significant increases in accuracy of time synchronization can be expected in a wider range of reception environments. NTT and FURUNO ELECTRIC Co., Ltd. have developed a receiver for GPS and other global navigation satellite systems (GNSS) that dramatically improves time-synchronization accuracy in areas with severe reception conditions such as among buildings and in mountainous areas.By integrating a new satellite signal selection algorithm developed by NTT into a time synchronization GNSS receiver (GF-88) from FURUNO, in addition to signals from satellites in line-of-sight locations, it has become possible to use multi-path signals (reflected or diffracted from buildings and other structures), which previously inhibited accuracy of time synchronization. In a real multi-path reception test environment, time error was reduced to approximately 1/5 of earlier values. This is a remarkable result in that it promises to enable time synchronization accuracy close to that obtained in open-sky reception environments with no obstructions, even in environments previously considered poor and unsuitable for accurate time synchronization, such as among buildings or in mountainous areas.Accurate time synchronization with Coordinated Universal Time (UTC), using Global Navigation Satellite Systems such as GPS, is used in a wide range of fields for synchronizing mobile base stations, financial trading, earthquake measurements, and other purposes. Particularly in recent years, mobile base stations based on TD-LTE and other TDD methods are spreading globally and require transmitted signals to be synchronized accurately, down to the microsecond, to avoid interference of signals between cells.However, in non-ideal reception environments such as among buildings or mountains, with structures surrounding the antennas the open area, where signals from navigation satellites can be received directly, is limited and reception of multi-path signals reflected from or diffracted by surrounding structures can significantly degrade the accuracy of time synchronization. Measures to improve accuracy of time synchronization have been studied in the past, including placing antennas in locations where they can receive signals directly from greater numbers of visible satellites, and also filtering based on the elevation of the signal direction or a signal strength threshold to exclude signals from non-line-of-sight satellites that cannot be seen directly from the receiver location. Even so, these earlier methods were not always able to ensure adequate accuracy, and also had issues with reliability.As such, NTT has developed a new GNSS receiver algorithm for selecting suitable navigation satellite signals and conducted measurements to verify the effectiveness of this algorithm.last_img read more

BUZZER BEATER | ‘Irresponsible dad’

first_img sports personality, who is popular but is not that good in his chosen field, is currently embroiled in a controversy when he refused to recognize his twin children with a former girlfriend.A source told the Buzzer Beater that the sports personality’s relationship with his ex lasted for almost a year but it ended when the latter was four months pregnant to save his career.“Nangangamba kasi si sports personality na kapag lumabas na nakabuntis siya ay masira ang career niya kaya nakipaghiwalay siya dun sa ex-girlfriend niya,” said the source.“Nagmamahalan sila at umabot pa sila ng isang taon. Natapos lang iyong relasyon nila nung four months pregnant na si girl. Pinuntahan pa nga daw si girl ng magulang ni guy, binigyan ng panggatas para manahimik.”“A few years since then, tahimik namang napalaki ni girl ang kambal niya hanggang magkaroon sila ng komunikasyon kamakailan, Gusto raw sana makita ni guy yung anak niya.”“Naka-set na yung date pero hindi naman sumipot si lalaki. Tapos nung magkita sila sa isang party sinubukan ni girl na lapitan si guy pero hinarang siya nung mga kaibigan ni guy.”“Sa totoo lang, wala namang balak na maghabol si girl kasi kaya naman niyang buhayin yung anak niya sa trabaho niya ngayon. Kumpara sa propesyon ni guy, mas mapera si girl.”“Ang wish lang ni girl na sana huwag gawin ni guy dun sa karelasyon niya ngayon yung ginawa sa kanya. Unlike kay girl, kapag ginawa niya yun sa GF niya ngayon, tiyak aawayin siya ng mga netizens at babansagang stock in jerk.”****Kiefer Ravena does not mind the controversies hounding him as he is focused on regaining his strength for a much-awaited debut with the Alab Pilipinas in the 2017 Asean Basketball League (ABL).Alab head coach Mac Cuan said the former Ateneo Blue Eagles star is close to regaining his full strength and will be ready for their semifinals match against the Singapore Slingers on April 2.“Ang pinag tutuunan niya ng pansin ay ‘yung progress ng recovery niya so he could be ready for Game 1,” said Cuan on Ravena, who is recovering from a hand injury during his stint with the Mighty Sports in Dubai.The Iloilo City-native Ravena has been controversial lately when alleged private photos of his were leaked through social media. The suspect who allegedly blackmailed Ravena has been caught.Ravena, a two-time UAAP MVP, had earlier said that he is excited to play for Alab as it will be a chance for him to represent the country, which he failed to do after being cut from the Gilas Pilipinas last year.“Syempre yung focus ko nandito talaga sa paglalaro kasi matagal na rin ako nahinto,” said Ravena. “My focus is double, triple. Hindi ako pwedeng magpaapekto sa mga nangyayari.”“Sa akin naman, kailangan maayos ‘yung pag-handle ng lahat. Hindi ko masyadong iniisip ‘yan kasi lahat naman ‘yan speculations pa lang. For me, titignan ko na lang kung ano sunod na mangyayari,” he added.Aside from his contract with the Alab Pilipinas, Ravena is also currently under contract as a development player with the Texas Legends team in the NBA Developmental League./PN[/av_textblock][/av_one_full] [av_one_full first min_height=” vertical_alignment=” space=” custom_margin=” margin=’0px’ padding=’0px’ border=” border_color=” radius=’0px’ background_color=” src=” background_position=’top left’ background_repeat=’no-repeat’ animation=”][av_heading heading=’BUZZER BEATER | ‘Irresponsible dad’’ tag=’h3′ style=’blockquote modern-quote’ size=” subheading_active=’subheading_below’ subheading_size=’15’ padding=’10’ color=” custom_font=”]By ADRIAN STEWART CO[/av_heading][av_textblock size=” font_color=’custom’ color=”]Sunday, April 2, 2017[/av_textblock][av_textblock size=” font_color=” color=”]last_img read more

Kent City volleyball team beats Fremont, loses to Spring Lake and Tri-County

first_img $9.99 Inappropriate / Offensive ENDS IN DEAL OF THE DAY Other Bestseller Thank you! This will help us improve your ad experience. We will try not to show you such ads again. Ads by Amazon × Thank you! This will help us improve your ad experience. We will try not to show you such ads again. Report a problem This item is… Other NBC Sports $37.99 Other Inappropriate / Offensive Fox Sports Go × 50PC Disposable Face MàSc/Mack Anti-Dust … × Shares LocalSportsJournal.comKent City went 1-2 in its volleyball quad at home on Monday.The Eagles topped Fremont in two sets, 25-13 and 17-15, but succumbed to both Spring Lake (25-14, 25-11) and Tri-County (25-19, 25-16) .Alyssa Hartzell had four aces and 18 assists for Kent City, Janelle Krueger had 10 assists and 27 digs, Paula Roberts had nine kills and 24 digs and Kaylee Campbell had three aces.The Eagles are now 8-23-1 on the season. Shop Now Bestseller Report a problem This item is… Share Inappropriate / Offensive DEAL OF THE DAY × Ads by Amazon (2) Displayed poorly Not relevant Add Comments (Max 320 characters) The League Other DEAL OF THE DAY Thank you! This will help us improve your ad experience. We will try not to show you such ads again. Report a problem This item is… Report a problem This item is… $14.99$18.00 Add Comments (Max 320 characters) Displayed poorly DEAL OF THE DAY (657) (7802) × (34271) ENDS IN Not relevant Add Comments (Max 320 characters) Not relevant × Not relevant Bestseller Add Comments (Max 320 characters) Inappropriate / Offensive $0.00 Displayed poorly Inappropriate / Offensive Displayed poorly (17612) Bestseller ENDS IN Bestseller Add Comments (Max 320 characters) Thank you! This will help us improve your ad experience. We will try not to show you such ads again. ENDS IN Inappropriate / Offensive Twelve Other Add Comments (Max 320 characters) Displayed poorly × $0.00 (822) DEAL OF THE DAY MIRITY Women Racerback Sports Bra… × Bestseller Mail Other Other Inappropriate / Offensive Bestseller Displayed poorly ENDS IN Report a problem This item is… $0.00 Add Comments (Max 320 characters) DEAL OF THE DAY The Sports Gene: Inside the Science of Extr… DEAL OF THE DAY Thank you! This will help us improve your ad experience. We will try not to show you such ads again. ENDS IN Not relevant ENDS IN Thank you! This will help us improve your ad experience. We will try not to show you such ads again. 0 Other Inappropriate / Offensive Bestseller DEAL OF THE DAY (31628) Report a problem This item is… Not relevant Thank you! This will help us improve your ad experience. We will try not to show you such ads again. Thank you! This will help us improve your ad experience. We will try not to show you such ads again. Report a problem This item is… Displayed poorly (117) ENDS IN FOX Sports: Stream live NFL, College Footbal… Add Comments (Max 320 characters) Report a problem This item is… $49.95 Not relevant Displayed poorly Share Not relevant $15.29$17.99last_img read more

Black Stars is Africa’s best bet to win World Cup

first_imgGhana Football Association President Kwesi Nyantakyi says the Black Stars remains Africa’s best shot at winning the 2010 World Cup in South Africa.No African side has ever won the competition since its inception in 1930 with the Cup having been won 18 times between just seven nations.A quarter-final finish is the farthest a team from the African continent has reached at the World Cup.But with South Africa having the chance to host the competition for the first time on the continent next month, an improved performance by an African side is expected. Africa is represented at the competition by hosts South Africa, Nigeria, Cameroon, Ivory Coast, Algeria and Ghana.Playing in group D which includes Serbia, Australia and three-time winners, Germany, Kwesi Nyantakyi tips the Black Stars as Africa’s surest bet for Cup glory.“The Black Stars commence camping on 24th May, 2010 in Paris, France in preparation for the 2010 FIFA World Cup in South Africa. “We expect the Black Stars to perform well beyond the placing at the 2006 FIFA World Cup in Germany,” The GFA President said at an Ordinary Session of the Ghana Football Association’s Congress on Thursday in Accra.“A World Cup in Africa is expected to be won by an African team. The Black Stars is the favourite Africa team to lay a claim to winning the World Cup.”Ghana, who reached the round of 16 in their debut four years ago and by far the best African performance at the 2006 Germany finals are making their second successive appearance.Source: Ghanafa.orglast_img read more