Site: Communications Research Centre (CRC)
3701 Carling Avenue
Box 11490, Station H
Ottawa, Ontario K2H 8S2, Canada
http://www.crc.doc.ca/crc

Date Visited: May 7, 1997

WTEC: K. Bhasin (report author), A. Mac Rae, W. Brandon

Hosts:

BACKGROUND

Communications Research Centre (CRC) is the Canadian government's leading communications research facility. It is responsible for conducting leading edge R&D to develop the Canadian communications infrastructure. One key objective is to support Canadian telecommunications firms in their efforts to remain globally competitive. It has a staff of over 250 engineers, scientists and technologists. Its policy allows for taking on activities to generate revenues. For example, contracts from Inmarsat to develop and flight test aeronautical satcom modems and antennas, as well as study contracts from ESA, have been completed. Its satellite communications systems research program focuses on the long-term planning of new communications systems and services and the R&D required to meet Canada's long-term needs, and to enhance Canada's international competitiveness. The program also supports the government's "Industry Canada" initiative in carrying out its statutory responsibilities to establish satcom policy, and to plan spectrum and orbit utilization to ensure that such services are provided in the most cost effective manner. Close liaison with industry and universities ensures that the research program complements the R&D performed by these sectors.

International Mobile Satellite Communications Program

Currently, CRC manages and provides technical leadership to the International Mobile Satellite Communications Program on behalf of the Canadian Space Agency. This 10-year cooperative venture between government and the private sector will develop and deliver state-of-the-art personal/mobile satellite communications technologies, products and services. Canadian industry was invited to submit proposals targeted at market-driven technology requirements and applications. To date, ten contracts totaling approximately $14 million have been placed with the private sector for the first three years of the program. The federal government's share is $6.9 million and industry funds the remaining $7.1 million.

MSAT

In early spring of 1996, the launch of TMI's MSAT-1 began a new era of mobile satellite communications services for Canadians. CRC was instrumental in initiating the MSAT program and demonstrating the technologies to prove the economic viability of the program. The program was transferred to industry, led by TMI Communications. The Government Telecommunications and Informatics Services markets MSAT services to government users. CRC continues, through its MSAT Applications Development Program, to provide engineering assistance to TMI and to work at the international level preparing for the next generation MSAT.

RESEARCH AND DEVELOPMENT ACTIVITIES

Application Development

CRC develops and demonstrates satellite extension of multimedia networks by running a number of applications demonstrations for various organizations. Among these are tele-robotics demonstrations for the Canadian Space Agency and its contractors, and international military field trials using both Telesat's Anik satellite and the NASA Advanced Communications Technology Satellite (ACTS). CRC is supporting the Global Interoperability for Broadband Networks (GIBN) project, which resulted from the G-7 Conference on the Information Society. CRC has proposed two projects for inclusion. The first of these is a five-node multimedia teleconferencing demonstration and the second is a multimedia cultural exchange between children in Canada, the United States, Japan and Norway. CRC will also support Japan in two of its experiments.

Ka-band Suitcase Terminal

A major demonstration of desktop video teleconferencing took place using NASA's ACTS satellite and several CRC Ka-band terminals, including a 0.5 meter prototype suitcase terminal. As a result of this demonstration, CRC signed a collaborative agreement with the U.S. Air Force's Rome Labs for the further development of the Ka-band suitcase terminal. It has also signed technology transfer agreements with industry. See Figures E.1. and E.2.


Fig. E.1. CRC suitcase terminal


Fig. E.2. Diagram of CRC suitcase terminal.

The Advanced Satcom Program

Initially approved by the Cabinet in 1994 as part of the Long-Term Space Plan and funded in part by the Canadian Space Agency, this program is managed by CRC and supported through internal system studies and R&D activities related to satellite onboard signal processing and Ka-band terminal development.

Communications Signal Design

CRC performs leading R&D in modulation, coding and multiple access techniques for mobile and broadband satcom. This is accomplished in part through collaboration with other research organizations (e.g., DRL, Germany) and Canadian universities and industry.

Microwave, Millimeter wave and High Speed Digital Circuits and Antennas

Through collaborative R&D agreements and contracts, Canadian firms continue to benefit from CRC's expertise in microwave technology. Several firms have developed new rf product capabilities. These include a 24 GHz planar array for traffic monitoring and a broadband, low profile PCS transmitter antenna. CRC has continued to offer substantial support in the area of microwave device noise measurement and millimeterwave device characterization. Several 29 GHz monolithic circuits were completed for a cooperative project with the Canadian Institute for Telecommunications Research to demonstrate wideband in-building communications. One of these, a switch, gave lower loss than any previously published work at this frequency. A successful three-way collaboration with VISTAR and Nanowave Technologies culminated in a very innovative integrated feed system for Ku-band terminals that delivered 10 watts of power, higher than any solid-state alternative, and at lower cost than conventional approaches. Research highlights include major new antenna concepts in the area of dielectric antennas, an area in which CRC is the world leader, and development of flexible microwave software programs for general purpose antenna and circuit design. A wideband receiver ASIC operating at over 500 MHz clock speed was completed, as well as oscillators and amplifiers using high temperature superconductors. Also a very high dynamic range receiver for digital radio broadcast reception was developed.

Optoelectronics Technologies

CRC is designing, fabricating and testing a novel high-frequency optoelectronic receiver. These receivers are currently being used in the performance characterization of low-loss fiber optic/microwave links for signal distribution in space-based phased-array antennas, wireless LANs and ground station antennas. Scientists at CRC have successfully demonstrated prototype low-loss polymer waveguides, splitters and optical taps on semiconductor substrates. These structures were fabricated using processing techniques that can be readily adapted to high volume processing and are expected to play a key role in the development of high-performance optoelectronic integrated circuits.

Propagation

During the past year, CRC has developed worldwide techniques for predicting clear-air fading distributions on low-angle, earth-space links and for predicting clear air interference distributions on trans-horizon links. These techniques have been adopted by the ITU-R. In addition, CRC's VHF/UHF prediction program, which is used extensively by other organizations, was improved to allow better prediction of location variability and median path loss.

CRC is the principal investigator for the successful sounding rocket payload that was launched in November 1995. This collaborative effort between CRC, CSA and NASA involved more than 20 scientists and will expand radio science knowledge important to designers of communications services for the Canadian North where the ionosphere can variously refract, absorb or scatter waves. The experiment involved the separation of two payloads connected by a 1.2 km tether.

Modeling and Predictions

A closed form analysis technique has been developed by which performance on North American IS-54 and higher data rate QPSK channels can be predicted on time series measurements of wideband radio channel data. Such a technique has never previously been available, except for low data rate cases where flat rather than selective fading takes place. Significant progress has been made in developing and validating models of the fields produced by portable transceivers when used by a human operator. Modeling of the near-field characteristics of cellular transceivers on dielectric objects was done and the results validated.

MPEG-2 Video Over ATM

CRC collaborated with two Ottawa Carleton Research Institute Network (OCRInet) partners to investigate the transmission of MPEG-2 compressed video over ATM networks. A PC-based client server system, capable of transmitting pre-compressed MPEG-2 bit streams, was developed and transmission tests were successfully conducted using Broadband Applications and Demonstration Laboratory (BADLAB) and OCRINet.

Radio Modem Technology

Signal design and processing research, sponsored by the Canadian Department of National Defense (DND), has led to the development of an improved method of adaptive equalization for signaling over time-varying, dispersive radiocommunications channels. For high frequencies (HF), this technique will double, and even triple, the data rates available with existing modem technology, and will also improve reliability of difficult circuits such as those found in Canada's north. Potential application of this technology to the digital cellular environment at VHF/UHF is being investigated.

First Digital Terrestrial Television Broadcast in Canada

Because of CRC's extensive expertise in digital television transmission, a consortium of American, Brazilian and Canadian broadcasters contracted with CRC to assess the benefits of using coded orthogonal frequency multiplexing (COFDM) as an alternative to the currently proposed VSB transmission scheme for digital terrestrial television broadcasting. In carrying out this study, system parameters to meet North American channel and broadcast requirements were defined and then validated in laboratory tests using a prototype system. Performance was further confirmed in an Ottawa field trial, which constituted the first digital terrestrial television broadcast in Canada.

Multimedia/Multinetwork Technology

As a prime participant in a three-year project involving six NATO countries, CRC has successfully completed its part to demonstrate and evaluate multimedia/multinetwork command, control and communications interoperability. The technology is now being deployed on some U.S. Navy platforms. In Canada, CRC has undertaken a second phase, which will lead to sea trials by the Canadian Navy.

Digital Radio Broadcast Standard

CRC has been instrumental in establishing the sound technical basis that allowed for a new transmission mode to be added to the European-developed Eureka 147 digital audio broadcasting standard. This mode, which permits doubling the spacing between on-channel transmitters and thus reducing implementation costs and increasing flexibility in locating transmitters, will now be included in all receivers manufactured for the world market. Industry Canada has formally adopted this standard for digital radio broadcasting in Canada.

FACILITIES

Broadband Applications and Demonstration Laboratory

The visiting WTEC team was given a tour of the BADLAB which is designed to demonstrate and test information highway applications using high-speed asynchronous transfer mode (ATM) fiber optic networks, with network extension via satellite and wireless (see Figure E.3). The staff has performed several experiments to investigate satellite/terrestrial interoperability based on ATM architecture.

BADLAB is Canada's ATM gateway to high speed communications networks around the world. It is a major node on the CANARIE National Test Network and an active partner in the Ottawa Carleton Research Institute Network Inc. (OCRInet). BADLAB is also connected to Europe through Teleglobe Canada's CANTAT-3 transatlantic fiber optic cable and will use satellites to connect to Japan. The lab is actively working with its European partners in broadband interoperability and applications trials.

BADLAB is collaborating with the Government Telecommunications and Informatics Services (GTIS) to explore broadband service options for a range of government clients across Canada. BADLAB is connected to GTIS through a 155 Mbps line. The lab is currently connected to OCRInet through two 45Mbps links, with the capacity to upgrade to 155 Mbps. The objective of this lab is to test and demonstrate various ATM test networks, such as OCRInet, Rnet, Wnet, LARG*net and others as they come online, making use of BADLAB's satellite link capability for network extension, and to make the lab available to industry, especially small and medium-sized high technology R&D companies across Canada, to develop applications that may be of commercial value.


Fig. E.3. BADLAB network configuration.

The broadband applications are being conducted in the following areas:

CONCLUSIONS

The Communication Research Center (CRC) is the premier research lab of Canada in advancing the state-of-the-art in satellite communications. It focuses on meeting Canada's needs in advance satellite communications while developing its industrial base. The program is balanced among spacecraft and ground segment technology, addressing regulatory issues, and bringing satellite communications into both Canadian and global information infrastructures.


Published: December 1998; WTEC Hyper-Librarian