Comsat, the Communications Satellite Corp., reported profits of $43.3 million ($5.41 a share) for the year ended Dec. 31 and said that operating revenues for the year soared 23 percent, reaching a record high of $409.5 million.

Meanwhile, United Services Life Insurance Co. reported higher earnings for the final quarter and full 1982 fiscal year.

In 1981, Comsat earned $40 million ($3.53) on revenues of $333.9 million.

The company said that the increase in revenues resulted principally from growth in the corporation's international communications satellite services and equipment manufacturing business.

The increase in earnings reflected higher revenues from services Comsat provides through the internationally owned Intelsat global satellite system and an increase in operating income derived from satellite systems and services. It also resulted from a decrease in the share of losses from the company's partnership interest in Satellite Business Systems, the company said.

United Services Life Insurance Co. reported 1982 net earnings of $20 million ($3.53 a share), including securities trading profits, and profits from operations of $18.9 million ($3.34). Net earnings for 1981 were $16.6 million ($2.93), and net operating profits were $15.3 million ($2.71).

The company's revenues for 1982 were $129.6 million, down from $166.6 million in 1981. Revenues for the final quarter of 1982 were $37.2 million, down from $53.9 million for the same quarter in 1981.

Net earnings for the quarter, including gains on securities transactions, were $6.8 million ($1.22) compared with net earnings in the final quarter of 1981 of $5.2 million (92 cents). The operating profit for the final quarter of 1982 was $6.4 million ($1.12) compared with $5.4 million (88 cents) for the same period a year earlier.

The company credited its results in 1982 to good mortality experience, strong sales, reduced policy loan demand and tight expense control.

During the fourth quarter, new individual life sales reached $361.2 million on $3.1 million of new premiums, compared with $388 million on $2.9 million of premiums in 1981. The company said that sales of group life, pension and variable annuities continued to be slow because of the weak economy. The company and its four subsidiaries market life and annuity products in specialty markets. International Bank of Washington, D.C. owns 35.7 percent of its outstanding shares.