NEW YORK (The Deal) -- Comtech Telecommunications (CMTL) - Get Report  said late Monday it has retained Citigroup Inc. and Proskauer Rose LLP to help the satellite communications firm explore options.

Melville, N.Y.-based Comtech, according to reports, began the process after receiving an expression of interest from a third party. The company offered no further details on the process in its statement, saying that there is no definitive timetable to complete the evaluation and cautioning that the review might not lead to a transaction.

Comtech is a manufacturer of advanced communications systems, including RF microwave amplifiers used by commercial and government customers. The company has long been discussed as a potential merger target, with European aerospace giant European Aeronautic Defence and Space Co. NV, according to sources at the time weighing a bid for the company back in 2008.

Comtech retained bankers in 2011 in response to activist pressure, but failed to find a buyer. In years past, a range of defense companies, including EADS, General Dynamics Corp., L-3 Communications Holdings Inc., Harris Corp. and BAE Systems plc have been mentioned as potential partners for Comtech.

A defense source reached Tuesday suggested Teledyne Technologies Inc. as a potential buyer this time around, though the source cautioned that Teledyne has a well-earned reputation of not overpaying for assets.

Shares of Comtech jumped 5%, or $2 apiece, on the initial reports, giving the company a market capitalization of about $590 million.

The shares continued higher by more than 1%, to $37.30 at open on Tuesday.

But Raymond James & Co. analyst Chris Quilty in a note urged caution when considering Comtech's upside, noting that the company's revenue has declined in 12 of the past 15 quarters. "With the stock currently trading at a multiple of 7.3 times consensus fiscal 2015 Ebitda, the stock is not inexpensive," Quilty said.

Further, some of Comtech's core technology is increasingly coming under pressure from competitors.

Quilty said that many potential bidders who specialize on satellite modem technology -- a list that includes Hughes Network Systems LLC, VT iDirect Inc. and ViaSat Inc. -- might sit on the sidelines for various reasons, potentially limiting the number of auction participants.