This is in such a boom phase that US bond yields would probably have to go to 20 per cent to put the brakes on shares of the most successful companies involved.
A problem for investors who like to buy low and sell high is that the key stocks have already had a phenomenal run.
In the most spectacular example, shares of the Finnish supplier of handsets and base stations, Nokia, have risen over 16-fold since September 1992. The group accounts for more than 30 per cent of the market capitalisation of the Finnish stock market.
But even this rise is trailing in the wake of a profits explosion. Nokia is being transformed almost overnight from a tiny company into a giant, with 1994 profits expected to rise between 200 and 300 per cent on 1993. At FM700 (pounds 91.90), the shares are comparatively modestly rated; earnings are expected to rise from FM11.6 for 1993 to FM36.3 for 1994, FM42.2 for 1995 and FM51.8 for 1996. Not only does that put the shares on a prospective p/e of about 13 for 1996 but, on past form, there will be many more profit upgrades by analysts following the company, so that reported figures are likely to be massively higher.
The Nokia story has been given an extra twist because of the arrival, in 1991, of a new president and chief executive, Jorma Ollila, who refocused the struggling company on the emerging mobile telecommunications market. The results have been spectacular. But there is much more to come, not only from the cellular market but also from new ventures such as video-on-demand.
Last but not least, the Americans have discovered Nokia: an ADS (Authorised Depositary Share), launched on the New York market in July, has helped take the US stake in the company over 50 per cent.
Globally, the fun may be just beginning. By the end of this year there are expected to be some 50 million mobile phone subscribers worldwide. That is around 1 per cent of the world population for a product that Ollila expects to become as ubiquitous as wrist-watches.
A spokesman for Motorola pointed out that the really explosive potential is in the high-population developing world, where governments are desperate to improve their communication networks to attract tourism and investment.
Motorola at dollars 57.87, with 1994 sales expected to exceed dollars 20bn, is a much larger company than Nokia but the cellular boom has put a rocket under its performance, too. Figures for the first nine months of 1994 showed sales up from dollars 12bn to dollars 15.8bn, net income up 53.2 per cent to dollars 1,045m and earnings per share of dollars 1.79 against dollars 1.20.
Best growth came in the cellular equipment division where sales leapt 65 per cent to make it the single largest business in the group. But good growth also came from paging and two-way radio and semiconductors.
Growth in demand is so fierce that the group has been capacity-constrained for the last two years. In the current year it expects to spend dollars 1.8bn on research and development and a further dollars 4bn, versus dollars 2bn the year before, on fixed investment. Analysts forecast earnings reaching dollars 2.49 for 1994 and over dollars 3 next year.
Another beneficiary of the boom is the Swedish telecommunications giant Ericsson, at Skr430 (pounds 36.75), which is unique in being able to supply systems for each of the three different standards in Europe, North America and Japan. However, investors have been concerned at the group's ability to control costs - in particular, those of a research and development programme that is absorbing something like a quarter of turnover. Bulls argue that the group is moving into the payback stage on this massive investment and that healthy profits growth in 1994 will accelerate next year. The group's business is global but Sweden has the world's highest ratio of cellular subscribers - one in 10 of the population.
The best-known British companies with exposure to this booming market are the service providers such as Vodafone and Securicor. But there are some relatively tiny companies supplying components, such as CML Microsystems at 269p, and the just-floated Filtronic Comtek at 120p. Investors are so wary of new issues that the shares have enjoyed a relatively subdued reception despite coming to market on the back of an explosive profits record.