Federal Reserve Chairman Ben Bernanke on Tuesday put the U.S. dollar squarely on the Fed's radar screen, saying its slide against other currencies has led to an "unwelcome" rise in U.S. inflation and may be a factor in inflation expectations. Bernanke also suggested that the Fed is unlikely to lower official interest rates further, though his remarks suggested that - barring a further rise in inflation expectations - the Fed probably won't contemplate higher rates until there is more stabilization in home prices.