The Pentagon is poised to consider whether more than 1,000 service members should have their valor awards upgraded to higher levels, the result of a broad review that also is expected to lead to the creation of new decorations to recognize significant contributions carried out in combat and remotely through unmanned aircraft and other military technology.

The recommendations are expected to be signed by Defense Secretary Ashton B. Carter on Wednesday, defense officials said Tuesday afternoon. Carter also will authorize the review of all award nominations for all service members who were recommended for the Silver Star, Distinguished Service Cross, Navy Cross, Air Force Cross and the Medal of Honor, a group that numbers well over 1,200.

The decisions follow a review called for by then-Defense Secretary Chuck Hagel in March 2014. He said at the time that he wanted to make sure modern combat veterans were appropriately recognized for their heroism and service, following years of complaints that significant acts of valor have been under-recognized.

Just 17 Iraq and Afghanistan veterans have received the Medal of Honor — far fewer than in Vietnam, World War II and other lengthy military campaigns. No living recipient ever received a Medal of Honor during more than eight years of combat in Iraq from March 2003 to December 2011, a detail that defense officials conducting the review noted.

Carter also is expected to authorize several policy changes to speed up the process by which heroism is recognized, with nominations for valor awards initiated within 45 days of the action and all nominations for the Silver Star and up reaching the defense secretary within a year. That follows years of criticism that award investigations have languished and led to few service members receiving significant valor awards while still on active duty.

The review of all major award nominations for the wars in Iraq and Afghanistan could be a significant effort. At least 635 soldiers, 346 airmen, 135 Marines and 15 sailors have received Silver Stars for actions in the two wars, with more receiving Bronze Stars with V device after being nominated for the higher award.

At least an additional 30 soldiers, nine airmen, 40 Marines, and eight sailors have received service crosses, which are considered one step below the Medal of Honor in recognized combat heroism. The 17 Medals of Honor have gone to 12 soldiers, three Marines and two Navy SEALs.

One of the more unexpected wrinkles following the awards review, however, is the proposed creation of a “C” device to denote meritorious service in combat. Defense officials said Tuesday it will go to service members who earn awards below the Bronze Star. Service members who earn an award with a “C” device will display it on their ribbons while in uniform.

Carter also is expected to tweak the policy for service members receiving an award with a “V” device, in light of there being a discrepancy in the services. For example, in the Army the “V” specifically connotes that the award was approved for a service member’s specific valorous action. In the Navy and Marine Corps, awards with a “V” have gone to troops who performed heroically on a single day, or meritoriously in combat over an extended period of time.

The “R” device, meanwhile, will be authorized for awards below the Bronze Star for service members who work remotely and show significant achievement in affecting specific actions on a battlefield. Its creation will follow a proposal during former Defense Secretary Leon Panetta’s tenure to create a so-called “drone medal” for achievement while operating unmanned aircraft. That proposal was eventually scuttled by Hagel, who noted the significant opposition it had among combat veterans because it would have outranked the Bronze Star. It was derisively called the “Nintendo medal” by some troops.

Defense officials said it would be possible to earn some ribbons with both a “C” and “V” device — with the “C” denoting meritorious service in combat and the “V” denoting a specific act or acts of valor.