So some went into networks which was viewed as a more commercially-viable thing. They learn to work out problems. He then pursued graduate study at the Massachusetts Institute of Technology and earned electrical engineering S. There was lots of student interest. Suddenly all the practitioners were interested in doing coding. Then the whole academic enterprise was slanted towards doing more theoretical work, more abstract work. I think the Defense Department always had plans that were somewhat more elaborate than its ability to carry them out.

In that field there is some stability there. Army Signal Corps before joining M. Since the program checking the program is always far more complex than the original program, the problem of finding out whether that’s correct or not is a far harder problem. Let me see if I can think of other examples. So nobody wanted to pay the money for these error-correcting devices. But I have to tell you to send it over again over this noisy channel.

That rate varied according to the transmission power and noise characteristics of a channel, but in practical communications systems, it might be only halfway to the Shannon limit.

What about the research going on now? You needed a lot of data transmission at that point, so these applications started becoming more important. All you needed was a way to add enough redundancy to the information so that errors rogert be corrected. Do you know if the military had any specific applications in mind?

Robert G. Gallager

The jobs were there for students. Personal tools Log in.


You can sell consumer electronics, where for twenty dollars you do things that would have cost millions of dollars back in the seventies. I guess I questioned what we were doing because I wondered why we were developing these very high-tech things which could be used only by the military, when I saw various civilian communication systems not really moving ahead very quickly.

A few people at that time were really starting to find out how to use these new ideas.

Oral-History:Robert Gallager – Engineering and Technology History Wiki

Historians will go through and find things written which were right, but that was not what was being said by most of the people who were guiding the field.

Retrieved from ” https: I found this new way of doing it which in fact turned into a nice, interesting, and fairly important new field of research, because it found a new way of proving these theorems.

Part of it is that the success in the communication field, most of the successes, have come out of a more scientific effort. Even though it was somewhat ivory tower, what’s been interesting to me is that most of these ideas have been used extensively since. So there tends to be a little less contact between the academic parts of the field, or the conceptual parts of the field, and the pragmatic parts of it.

He’s at Zurich now, at ETH.

Low-density parity-check codes

There wasn’t research money for thesid on these other things. You just say this is what you have to know, and this is how you use it. In fact, when I was in the army, that’s what we were working on, all of these techniques for sending data around and processing data, rrobert that army commanders would know what was going on in the field.


There were a lot of ideas around for doing that. It was a very stable business. Switching theory has been very well developed over the years.

robert gallager phd thesis

You don’t think ahead of time to say, what’ll I do if this person screws up? In some rboert you might say, in that case I’ll just shut the system down and start over again. The courses I was taking that were most interesting were the ones in information theory and various related subjects. The value of learning more mathematics and knowing how to use the mathematics in engineering.

Explained: Gallager codes | MIT News

Students who want to become faculty members perceive the process for getting tenure as being a competition between a huge number of people. Most of the use of communication systems in those days was for voice.

The way the ARPANET worked, because they were worried about having enough storage at the other end, there would have to be another packet coming back saying: Now networks enter the picture. It was all just lots of facts.

To detect you only have to know that something has gone wrong, you don’t have to know what it is. It was a monopoly, it was clear what the telephone business was, people wanted telephones, and telephones remained about the same.

robert gallager phd thesis

Archived from the original PDF on April 25, There were really four packets that went back and forth for each one character of data that comes in. We had a tri-services contract at MIT at the time, which meant money coming into one funnel essentially from the army and the air force and the navy.