М.V. Indenbom – Ph.D. (Eng.), Senior Research Scientist,

JSC «All-Russian Research Institute of Radio Engineering»

E-mail: mindenbom@mail.ru

This paper analyzed influence of reception paths nonlinearity on efficiency of jamming suppression in adaptive active phased antenna arrays (APAA) for simplest nonlinearity model. APAA have analog-digital convert on high (carrier or intermediary) frequency so that signal relative frequency band is no more than several percent. The analytic complex signal formed in digital reception modules (DCM). There is consider influence only of integrate nonlinearity of analogy-digital of APAA canals. A jamming and noise assumed is distributed on normal law and nonlinearity of any canals are identity. 

The functional dependence between input complex signal and complex signal in digital reception module (DCM) output deduced. The expression for correlation matrix of noise and jamming on DCM outputs is found with take into account nonlinearity influence. On base analysis of eigen-values and eigen-vectors of correlation matrix found expressions for intersection point of thirds order I3 for  reception canals in dependence from expected maximum jamming power in DCM input and number of elements of APAA. 

It been shown that reception paths nonlinearity more substantial in case several power jamming and results to reduce efficiency of jamming cancellation and maximal jamming sources number because rank r of correlation matrix in noise absent conditions increase proportional to S3 where S is number of jamming is much more 1. After than as rank r reached to number of APAA elements efficiency of jamming suppression is quickly fall. Got expressions may be used for simulation adaptive APAA and for approximate estimation needed dynamical band of APAA canals by simple calculations.

1. Ratynskij M.V. Adaptacija i sverhrazreshenie v antennyh reshetkah. M.: Radio i svjaz'. 2003. [in Russian]
2. Procedura ispytanij dlja izmerenija urovnja tochki peresechenija tret'ego porjadka (IP3) priemnikov radiokontrolja. Mezhdunarodnyj sojuz jelektrosvjazi. Rekomendatsii MSJe-R SM.1837. 2008. [in Russian]
3. Levin B.R. Teoreticheskie osnovy statisticheskoj radiotehniki. Kn. 1. M.: Sov. radio. 1974. [in Russian]
4. Gel'fand I.M. Lekcii po linejnoj algebre. M.: Nauka. Fizmatgiz. 1971. [in Russian]
5. Lankaster P. Teorija matric. M.: Nauka. Fizmatgiz. 1978. [in Russian]