Performance of multi level digital FM modulation scheme is studied for a portable microwave link (FPU) in the 7GHz band. The advantage of the modulation scheme is that it can utilize a conventional FPU modem as a digital modem by adding a digital process unit. We have experimentally developed an eight level digital process unit to confirm its performance when applied to an FPU modem. As the result of a test bed experiment, it is confirmed that a bit rate of 45Mbps can be achieved.
We have defined the criticality, which indicates the objective measure of the difficulty for digital coding, as an output bit-rate of a DCT encoder with fixed quantizer. We have developed the criticality measurement equipment based on MPEG-2 Simple Profile, and measured the criticality of a test sequences and also measured the criticality of terrestrial TV programs for a week. The statistic such as frequency distribution of each criticality was obtained. According to the statistic of the criticality for each program genre, the criticalities of news, sports and culture program tend to be high. The criticality of satellite broadcast was also measured, and the distribution of the criticality for satellite broadcasting was almost the same as the terrestrial service.
Subjective assessment test for MPEG-2 SP@ML (Simple Profile at Main Level), MP@ML (Main Profile at Main Level) and NTSC was conducted using fifteen different sequences. The bit rate for the SP@ML and MP@ML were 4,6,9 and 15 Mbit/s. The test was performed based on the double-stimulus continuous quality-scale (DSCQS) method described in ITU-R Rec. BT. 500-5. The test results show that approximately 9Mbit/s is an appropriate bit rate for digital broadcasting to keep the comparable picture quality distribution with NTSC.
We have estimated the picture quality for digital broadcasting based on the criticality distribution of TV programs. This analysis was conducted for overall TV programs as well as programs of different genres such as sports and drama. The following results are described in this document : 1) The degradation of picture quality over DSCQS 18% appears about O.1% of the time for overall TV programs, when coded using MPEG-2 MP@ML at 9 Mbit/s and observed at the viewing distance of 6H. 2) Differences of degradation among different genres increase at lower bit rate. For example, the degradation over DSCQS 18% appears, at 6 Mbit/s, about 5% of the time for sports programs whereas about 2% of the time for overall TV programs.
In the TBS Broadcast Center that started an operation on October, 1994,we digitalized the audio signal transmission. we adopted AES3-1992 as a transmission standard. We used the 75-ohm coaxial cable (5C-FB). We used a transformer for the purpose of an impedance matching between a machine and a cable. We also adopted AES-3ID-xxxx for a portion.
In October 1994 the TBS began its operation into the new Broadcast Centre. The Master Control System of the TBS's new Broadcast Centre has been developed to specification to provide flexibility and future expantion. The system is highly redandant and protect from failor. The control panel required interactive touch panels, provide user features such as menu-driven source selection. Also discussed are several new concepts and technologies relating to alarm system and expert system.
This paper discribes the systems for circuit control in new broadcasting center. We use digital system, circuit management system, and circuit control system. The signals, both video and audio, are digitized in circuit control area and distributed to each section in the station with no degradation of signal quality. Circuit management system was designed as a part of the total system. Through LAN, this system executes the following functions : circuit reservations, confirmations, referencing, fee management, and administration of outcome. Circuit control system can receive schedule data from circuit management system, and is directed to equipment control.
NHK Kobe Broadcasting Station Building suffered serios damage from the Great Hansin Earthquake. Restricting argument to structural matter, we report the result on investigation and measures such as emergency reinforcement of building, and so on.
Broadcast facilities of NHK Kobe station were seriously damaged by the Great Hansin Earthquake, however, it did not come to a suspension of broadcast service. The control and transmit facilities, which are vital to broadcast function, are set up in the quake-resistant equipment installation rack, and the present quake-resistant structure of the rack and the damage are described in this report.
At 5 : 46 in the morning of January 17 in 1995,a large scale earthquake took over 5,500 people's lives and their properties. This earthquake also has damaged NHK Kobe Broadcasting Station Building and utilities. The staffs of the Kobe Station were coming to the office right after the earthquake. They struggled to keep programs on-aired, Such as eye-catching picture of the "Skin Back Recorder", long run news continued.
Sun-TV suffered a lot of damage from Great Hanshin Earthquake, which broke out on 17th Jan. 1995 though we usually take countermeasures in case of earthquake, for instance. We are reporting the damage gotten in the system, and how to have managed to keep our broadcasting system work well in such the bad situations.
The Resolution of picture is consist of HDTV Camera and HDTV-NTSC converter characteristic. To attest this idea we measure the HDTV Camera and HDTV-NTSC signal converter characteristic. Result of measurement resolution of converted picture from HDTV camera higher than NTSC conventional camera.