The Federal Reserve gathers for its first policy meeting this year amid increasing signs that the U.S. economy is doing better, but the improvements don’t look strong enough to make officials change their easy-money policies supporting growth.

Fed officials are expected to be slightly more upbeat on growth in 2011, a change that would be reflected in the central bank’s statement released at the end of the Federal Open Market Committee meeting, at 2:15 p.m. EST Wednesday.

However, upgrades to the 2011 gross-domestic-product forecast are likely to be only marginal–not enough to bring down the unemployment rate significantly or to cause concerns that consumer prices might shoot up. That should keep the Fed’s $600 billion bond-purchase program intact, given also that none of the new officials voting this year have said they want to call for an early end to the program at this two-day FOMC meeting, which started Tuesday.

Fed officials “will be careful not to sound too positive on the economy. They want to avoid sending the signal that they could back off the bond purchases,” said Jim O’Sullivan, chief economist at MF Global in New York.

To kick-start a disappointingly slow recovery, the Fed resumed buying government bonds in November 2010, but suggested it could scale back purchases if the economy picked up. Though the outlook has since improved, the central bank looks poised to complete its purchases in order to ensure that unemployment keeps on falling and prices continue moving up a bit from low levels. The Fed has already bought some $240 billion in Treasurys, and the program is due to end in June.

Central bank officials recently have been guardedly optimistic about the economy. Fed Chairman Ben Bernanke on Jan. 13 said he is more confident about the recovery than a few months ago, adding that the bond purchases are helping the economy by boosting stock markets.

Bernanke said he expects GDP to rise by up to 4% this year, compared with less than 3% in 2010. The chairman’s projection provides a good indication of what is likely to emerge as the latest consensus forecasts from the Fed’s policy-setting body. In its most recent prediction, made in November, the FOMC saw the economy growing by 3.6% at best in 2011.

The economy, helped by the recent tax-cut package, is expected to firm this year. The payroll tax reduction should help keep consumer spending up, following the solid retail sales gains seen during the recent holiday shopping season. Encouraged by the economy’s improvement, companies look set to hire more workers in the months ahead.

However, the hole caused by the recession was so big that Fed officials don’t appear ready to unwind their huge monetary stimulus. Since December 2008, the Fed has kept short-term interest rates close to zero and bought nearly $2 trillion in mortgage and government bonds. Compared with other post-World War II recoveries, the current one is proceeding at a snail’s pace.

Even though the overall economy should improve this year, certain sectors–most notably, housing–are either expected to remain weak or worsen. The U.S. unemployment rate, currently at 9.4%, is seen coming down only slowly, which should keep income growth contained.

Global prices for food and raw materials have been soaring recently, leading European Central Bank President Jean-Claude Trichet to worry about inflation rising too much. But the Fed’s preferred price gauge, which strips out energy and food prices that tend to be volatile, remains well within the U.S. central bank’s comfort zone of just under 2%.

All this should ensure the Fed will leave policy unchanged as officials assess how long it takes for the stronger economy to cut joblessness and boost prices.

The bond program isn’t universally embraced by FOMC members. Of the four regional Fed presidents who get a vote this year, only Charles Evans of Chicago supports it. Richard Fisher of Dallas and Charles Plosser of Philadelphia have been outspoken critics. Narayana Kocherlakota of Minneapolis has questioned its ability to cut unemployment.

Still, none of the new members have shown a strong inclination to change course now that the decision has been taken. The four new regional presidents join seven permanent voters on the Fed’s policy-making body: six Fed governors — one seat is vacant as Nobel laureate economist Peter Diamond awaits Senate confirmation — and the New York Fed president, who have all voted in favor of the bond purchases.

As he prepares for his congressional testimony, Bernanke therefore looks poised to get the full backing of the committee for the controversial bond program, which was attacked by senior Republicans, who fear it will lead to runaway inflation.

Though there’s a chance that Fisher and Plosser could dissent, the “much more likely outcome is that the vote is unanimous,” said Michael Feroli, a Fed watcher at J.P. Morgan Chase.