A sequenced-gain receiver is shown in Figure 1 111. Operation of the receiver can be understood from the timing diagram of Figure 2. The first RF amplifier is active until signal emerges from the SAW delay line when it is powered down and the second RF amplifier is powered up. Some time later, the cycle is repeated.With adequate pulse repetition frequency (PRF), the modulated data can be recovered completely. If the duty factor is small, the average power supply current is low, since the baseband circuits after the detector require much less current than the RF section. This efficiency comes at the expense of RI? sensitivity, due to noise aliasing caused by switchingthe amplifiers. Performance is intermediate to super-regenerative and superheterodyne receivers.Configured for lkbaud data, sensitivity exceeds -100dBm. The absence of oscillators obviates receiver radiation. Inclusion of the SAW coupled resonator bandpass filter at the input protects the high gain first amplifier from clipping on unwanted signals (Figure 3). The SAW delay line also provides selectivity, which limits the effects of noise aliasing of the first amplifier. The result is a selective, sensitive, RF quiet, low cost, fixed tuned data receiver in a small package [23.The chip contains the switched RF amplifiers, Ah4 detector, baseband lowpass filter and amplifier, comparator, data output driver, and pulse generator. Avariety of end applications for the resulting References 111 "Sequential Amplifier", U.S. Patent # 5,357,206. RFM

Analog s i g n a l processor u t i l i z i n g Charge Coupled Device (CCD) and Surface Wave Device (SWD) Two technologies i n conplementary noles can o f f e r c o s t , s i z e and power advantages over d i g i t a l techniques. key components c u r r e n t l y under d e v e l n p m n t a r e a CCD r e f o r m a t t i n g memory and an SWD c h i r p Z t r a n s f o r m module which a r e i n t e r c o n n e c t e d t o p e r f o r m h i g h speed r a d a r doppler processing. row-colunn interchange on square b l o c k s o f t h e sampled v i d e o data. up converted and read i n t o t h e SWD CZT which performs a 64 p o i n t s p e c t r a l a n a l y s i s o f t h e contents o f each range b i n . r a t e and 50 dB dynamic range w i l l be demonstrated. The CCD memory samples and s t o r e s t h e r a d a r video o v e r 66 r e t u r n s , then reformats i t by p e r f o r m i n g a The reformatted data i s then f i l t e r e d and The component development w i l l be discussed and progress toward system design goals o f a 12.5 Wiz data I n t roduc t i on The p o t e n t i a l cost, s i z e and power savings i n an analog s i g n a l processor conbining t h e c o n p l e w n t a r y t i m e -b a n d r i d t h p r o p e r t i e s o f charge coupled devices (CCDs) and surface wave devices (SUDS) make i t h i g h l y c o m p e t i t i v e w i t h d i g i t a l techniques.' One o f t h e most a t t r a c t i v e s y s t e m a p p l i c a t i o n s i s a h i g h speed p r ocessor f o r pulse-doppler r a d a r used t o r e s o l v e r e t u r n s f r o m a number o f t a r g e t s having d i f f e r e n t v e l o c i t i e s i n t h e S a m range c e l l . ' T h i s system can be implem n t e d u s i n g a h i g h speed spectrum a n a l y z e r based on the powerful c h i r p Z t r a n s f o r m (CZT) a l g o r i t h m r e a l i z e d w i t h SWD t r a n s v e r s a l f i l t e r s and a h i g h speed CCD analog memory which reformats t h e r a d a r video f o r a p p l i c a t i o n t o t h e CZT f o r m u l a t i o n o f t h e CZT a l g o r i t h m using t r a n s v e r s a l f i l t e r s 5 and numerous exanples u t i l i z i n g SWDs i n t h a t appl i c a t i on 3 3 ' i 6 -' h ave been documented e x t e n s i v e l y , as have a nunber o f a r c h i t e c t u r e s f o r CCD r e f o r m a t t i n g memories. 3 , 4~1 0 This paper w i l l focus on t h e p a r t ic u l a r c o n f i g u r a t i o n o f each module (CCD memory, SWD CZT) as chosen t o meet t h e p r e l i m i n a r y system r e q u i r ements. The mathematical System C o n f i g u r a t i o n s A b l o c k diagram o f t h e analog doppler processor i s shown i n Figure 1, and p r e l i m i n a r y parameters a r e described i n Table 1. In-phase and quadrature components o f t h e radar video a r e f u r n i s h e d b y a synchronous d e t e c t o r and a r e s t o r e d i n separate range s t o r e s modules. Each range s t o r e module c o n s i s t s o f a nurrber o f 66 x 66 c e l l CCD memory b l o c k s . For p r e l i m i n a r y system t e s...

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O s c i l l a t o r s have been constructed using surface wave resonators as t h e frequency c o n t r o l element a t 194 MHz which a r e v o l t a g e tunable over a 30 kHz range. The s h o r t term s t a b i l i t y w i t h a 10 msec averaging time i s 1.5 x The two-port surface wave resonator has advantages o v e r one-port resonators ( e i t h e r surface wave o r p l a t e mode) f o r use i n o s c i l l a t o r s . The loaded Q and excess loop g a i n a r e c o n t r o l l e d t o e x e r c i s e the compromise between a v a i l a b l e t u n i n g range and s h o r t term s t a b i l i t y . l n t r o d u c t i o n The Surface Acoustic Wave (SAW) resonator i s a new element w i t h resonant behavioSm4 (Figure I ) . many resonators, i t i s u s e f u l as an o s c i l l a t o r f r equency c o n t r o l element. The r e s u l t i n g o s c i l l a t o r s a r e u s e f u l f o r many appl i c a t i o n s because o f t h e i r s h o r t term s t a b i l i t y i n t h e 200-IO00 MHz frequency range p r e v i o u s l y served by LC o s c i 1 l a t o r s , lower frequency o s c i l l a t o r s w i t h frequency m u l t i p l i e r s , and, t o a l e s s e r extent, SAW delay l i n e o s c i l l a t o r s . The long term s t a b i l i t y o f t h e SAW resonator has y e t t o be demonstrated. o f these o s c i l l a t o r s extends t h e i r u t i l i t y by allowing, f o r example, long term c o n t r o l from another source, doppler t r a c k i n g o f moving targets, or p e r i o d i c remote adjustment o f frequency. The SAW resonator has advantages o v e r e i t h e r SAW delay l i n e s or p l a t e mode resonators f o r use i n UHF o s c i l l a t o r s . L i k e The a d d i t i o n o f e l e c t r o n i c f i n e t u n i n g Fig. I Surface Acoustic Wave Resonator a t 200 M H r C i r c u i t Conf i q u r a t l o n s A wide v a r i e t y o f c i r c u i t c o n f i g u r a t i o n s e x i s t f o r t h e r e a l i z a t i o n o f o s c i l l a t o r s . The two shown i n F i g u r e 2 were used w i t h p a r t i c u l a r success by t h e author. connection o f amp1 i f i e r , resonator, and phase s h i f t e r . O s c i l l a t i o n s w i l l be maintained a t t h e frequency which a l l o w s 2nn phase s h i f t around t h e e n t i r e loop. Thus v a r i a t i o n s i n t h e i n s e r t i o n phase s h i f t o f t h e phase s h i f t network w i l l tune t h e o s c i l l a t o r o v e r t h e l i m i t s of t h e t r a n s i t i o n phase region shown i n F i g u r e I . To tune t h e frequency o v e r an a p p r e c i a b l e p o r t i o n o f the phase t r a n s i t i o n region, i t i s necessary t o e i t h e r prov i d e more g a i n than i s necessary t o m a i n t a i n o s c i l l a t i o n Tho b a s i c C o n f i g u r a t i o n c o n s i s t s of tandem a t t h e c e n t e r frequency (where the i n s e r t i o n loss o f the resonator i s lowest) o r p r o v i d e a phase s h i f t n e twork whose amp1 i tude response i s t h e complement o f t h e amp1 i tude response o f the resonator....