Sirena was an early series of Soviet and Russian radar warning receivers, devices with Sirena designations first were reported on the MiG-21 (fighter) (Western: MiG-21 FISHBED). The model numbers are in the SPO series. The SPO-10 is described as at the rough technology level of U.S. Vietnam War era equipment.  They are able to recognize different Western threats.
Other variants, including the model 3M with no blind spots, have been described on the MiG-23 (fighter), MiG-25 (fighter) and reconnaissance aircraft (Western: MiG-25 FOXBAT. Another was on the Yak-28 (bomber) (Western: Yak-28 BREWER) electronic warfare variant. There is also version for the Su-25 FROGFOOT
- Airborne Electronic Warfare (Ew) Systems, Sirena-3 radar warning receiver (Russian Federation)
- Friedman, Norman, The Naval Institute Guide to World Naval Weapons Systems, 1997-1998, U.S. Naval Institute Press, p.
- GlobalSecurity.org, Su-17,-20,-22 FITTER (SUKHOI)