TELK OMNIKA , V ol. 12, No . 3, September 2014, pp . 525 532 ISSN: 1693-6930, accredited A b y DIKTI, Decree No: 58/DIKTI/K ep/2013 DOI: 10.12928/telk omnika.v12.i3.125 525 Quantiz ed Feedbac k Contr ol of Netw ork Empo werment Amm unition With Data-Rate Limitations F ang Jin 1 , Zhi-hua Y uan* 1 , Qing-Quan Liu 1,2,3 , and Zhang Xing 4 1 College of Inf or mation Science and Engineer ing, Shen y ang Ligong Univ ersity No . 6, Nan Ping Zhong Road, Hun Nan Xin Distr ict, Shen y ang, 110159, Chin a 2 Shen y ang Institute of A utomation, Chinese Academ y of Sciences No . 114, Nanta Street, Shenhe Distr ict, Shen y ang, 110016, China 3 Allwin T elecomm unication CO ., L TD No . 6, Gaoge Road, Hun Nan Xin Distr ict, Shen y ang, 110179, China 4 Ag r icultur al De v elopment Bank of China br anch in Liaoning pro vince China *Corresponding author , e-mail: lqqneu@163.com Abstract This paper in v estigates quantiz ed f eedbac k control prob lems f or netw or k empo w er ment amm uni- tion, where the sensors and the controller are conne cted b y a digital comm unication netw or k with data-r ate limitations . Diff erent from the e xisting ones , a ne w bit-allocation algor ithm on the basis of the singular v alues of the plant matr ix is proposed to encode the plant states . A lo w er bound on the data r ate is presented to ensure stabilization of the unstab le plant. It is sho wn in our results that, the algor ithm can be emplo y ed f or the more gener al case . An illustr a tiv e e xample is giv en to demonstr ate the eff ectiv eness of the proposed algor ithm. K e yw or ds: netw or k empo w er ment amm unition, bit-allocation algor ithms , data-r ate limitations , quantiz ed control, f eedbac k stabilization Cop yright c 2014 Univer sitas Ahmad Dahlan. All rights reser ved. 1. Intr oduction Netw or k ed control systems ha v e attr acted g reat interests in recent y ears [1-3]. In this paper , w e study quantiz ed f eedbac k control prob lems f or netw or k empo w er ment amm unition with limited inf or mation about the plant states . This prob lem ar ises when t he state measurements are to be tr ansmitted to the controller via a limited capacity comm unication channel. Issues of the type discussed are motiv ated b y se v er al pie ces of w or k in the recent liter- ature . The research on the inter pla y among coding, estimation, and control w as initiated b y [4]. A high-w ater mar k in the study of quantiz ed f eedbac k using data r ate limited f eedbac k channels is kno wn as the data r ate theorem that states the larger the magnitud e of the unstab le poles , the larger the required data r ate through the f eedbac k loop . The intuitiv ely appealing result w as pro v ed [5-8], indicating that it quantifies a fundamental relationship betw een unstab le ph ysical sys- tems and the r ate at which inf or mation m ust be processed in order to stab ly control them. When the f eedbac k channel capacity is near the data r ate limit, control designs typically e xhibit chaotic instabilities . This result w as gener aliz ed to diff erent notions of stabilization and system models , and w as also e xtended to m ulti-dimensional systems [9-12]. Liu and Y ang in v estigated quantiz ed control prob lems f or linear time-in v ar iant systems o v er a noiseless comm unication netw or k [13]. Fur ther more , Liu addressed coordinated motion control of autonomous and semiautonomous mobile age nts in [14], and der iv ed t he condition on stabilization of unmanned air v ehicles o v er wireless comm unication channels in [15]. F or the m ulti-state case , one needs to present an optimal bit-allocation algor ithm to reg- ulate the tr ansmission of inf or mation about each mode such that stabilization can be guar anteed f or all modes . In the liter ature , the bit-allocation algor ithms w ere on the basis of the eigen v alues of Receiv ed Apr il 25, 2014; Re vised J uly 4, 2014; Accepted J uly 24, 2014 Evaluation Warning : The document was created with Spire.PDF for Python.
526 ISSN: 1693-6930 the system matr ix A . Namely , it states the larger the magnitude of the unstab le eigen v alues , the larger the required data r ate through the f eedbac k loop . Thus , it needs to tr ansf or m the system matr ix A b y a real tr ansf or mation matr ix H 2 R n n to a diagonal matr ix J or a Jordan canoni- cal f or m J (i.e ., J = H AH 1 ) in order to decouple its dynamical modes to achie v e an optimal bit-allocation algor ithm. Ho w e v er , f or the more gener al matr ix A , modal decomposition might not be possib le and putting the system matr ix into Jordan canonical f or m gener ally requires a tr ans- f or mation matr ix with comple x elements such that the e xisting bit-allocation algor ithms do not w or k. In this paper , w e present a ne w bit-allocation algor ithm f or the more gener al matr ix A . The algor ithm proposed here is on basis of not the eigen v alues b ut the singular v alues of the system matr ix A . In par ticular , w e quantiz e , encode the plant states b y an adaptiv e diff erential coding str ategy . The rest of the paper is organiz ed as f ollo ws . In Section 2, the prob lem f or m ulation is pre- sented. Section 3 presents the bit -allocation algor ithm f or stabilization. The results of n umer ical sim ulation are presented in Section 4. Conclusions are stated in Section 5. 2. Pr ob lem Form ulation Consider the control system of netw or k empo w er ment amm unition descr ibed b y the state equation X ( k + 1) = AX ( k ) + B U ( k ) (1) where X ( k ) 2 R n is the measur ab le state , and U ( k ) 2 R p is the control input. A and B are kno wn constant matr ices with appropr iate dimensions . The f ollo wing is assumed to hold: Assumption-1: The pair ( A; B ) is controllab le , and the plant states are measur ab le; Assumption-2: The initial condition X (0) is a r andom v ector , satisfying E k X (0) k 2 < 0 < 1 ; Assumption-3: The sensors and controllers are geog r aphically separ ated and connected b y er- ror less , bandwidth-limited, digital comm unication channels without time dela y . The channel is also assumed t o be a time-in v ar iant, memor yless channel. Then, the encoder and de- coder ha v e access to the pre vious control actions . Let ^ X ( k ) denote the decoder’ s estimate of X ( k ) on the basis of the channel output. Our simplified model of the channel neglects the eff ects of netw or k-induced dela ys and data dropout, and f ocuses on the bit-allocation algor ithm. Then, w e ma y implement a quantiz ed state f eedbac k control la w of the f or m U ( k ) = K ^ X ( k ) : (2) As in [9], the system (1) is said to be asymptotically MS-Stabilizab le via quantiz ed f eed- bac k if f or an y initial states X (0) , there e xists a control policy relying on the quantiz ed data such that the states of the closed-loop system are asymptotically dr iv en to z ero in the mean square sense , namely lim sup k !1 E k X ( k ) k 2 = 0 : (3) Our main task is to present a bit-allocation algor ithm f or the more gener al matr ix A , and to der iv e the sufficient condition on the data r ate f or stabilization of the system (1) in the mean square sense (3). 3. The Bit-Allocation Algorithm This section deals with the stabilization prob lem under data r ate constr aints , and presents a bit-allocation algor ithm f or the more gener al matr ix A . Since the matr ix A 0 A is a real symmetr ic matr ix, there e xists a real or thogonal matr ix H 2 R n n that diagonaliz es A 0 A = H 0 2 H . Here , w e define := diag [ 1 ; ; n ] where i denotes the i th singular v alue of A ( i = 1 ; ; n ). TELK OMNIKA V ol. 12, No . 3, September 2014 : 525 532 Evaluation Warning : The document was created with Spire.PDF for Python.
TELK OMNIKA ISSN: 1693-6930 527 The coding technique presented in this paper is an adaptiv e diff erential coding str ategy . Define X ( k ) := H X ( k ) ; ~ X ( k ) := H ^ X ( k ) : Then, the system (1) ma y be re wr itten as X ( k + 1) = H AH 0 X ( k ) + H B K H 0 ~ X ( k ) : Let ~ X ( k ) := H ( A + B K ) H 0 ~ X ( k 1) and Z ( k ) := X ( k ) ~ X ( k ) denote the prediction v alue and the prediction error of X ( k ) , respectiv ely . Here , w e set ~ X (0) = 0 . Then, Z (0) = X (0) . It is sho wn in Assumption-3 that the encoder and decoder ha v e access to the pre vious control actions , update their estimator and scaling in the same manner , and obtain the same prediction v alue . Then, w e ma y quantiz e , encode Z ( k ) , and tr ansmit the inf or mation of Z ( k ) via a digital channel. Let ^ Z ( k ) and V ( k ) denote the quantization v alue and the quantization error of Z ( k ) , respectiv ely . Then, ^ Z ( k ) = Z ( k ) V ( k ) : The v alue of ^ Z ( k ) ma y be computed on the basis of the channel output at the decoder . Then, the decoder’ s estimate is defined as ^ X ( k ) := H 0 ( ~ X ( k ) + ^ Z ( k )) : Thus , ^ X ( k ) ma y be obtained b y the controller . Let Z ( k ) := [ z 1 ( k ) z 2 ( k ) z n ( k )] 0 . As in [16], giv en a positiv e integer M i and a nonneg- ativ e real n umber i ( k ) ( i = 1 ; ; n ), define the quantiz er q : R ! Z with sensitivity i ( k ) and satur ation v alue M i b y the f or m ula q ( z i ( k )) = 8 < : M + ; if z i ( k ) > ( M i + 1 = 2) i ( k ) ; M ; if z i ( k ) ( M i + 1 = 2) i ( k ) ; b z i ( k ) i ( k ) + 1 2 c ; if ( M i + 1 = 2) i ( k ) < z i ( k ) ( M i + 1 = 2) i ( k ) (4) where define b z c := max f k 2 Z := k < z ; z 2 R g . The indeces M + and M will be emplo y ed if the quantiz er satur ates . The algor ithm to be used here is based on the h ypothesis that it is possib le to change the sensitivity (b ut n ot the satur ation v alue) of the quantiz er on the basis of a v ailab le quantiz ed measurements . Ho w e v er , it is unclear in [16] ho w m uch each M i should at least be in order to guar antee stabilization of the system (1). A lo w er bou nd of each M i f or stabilization will be presented in our results . Based on the quantizatio n algor ithm abo v e , w e can constr uct a code with code w ord length r i ( i = 1 ; ; n ). Let ( c 1 c 2 c r i ) denote the code w ord corresponding to z i ( k ) . Namely , z i ( k ) is quantiz ed, encoded, and tr ansf or med into the r i bits f or tr ansmission. Then w e ma y compute c j 2 f 0 ; 1 g ( j = 1 ; ; r i ) ( c 1 c 2 c r i 1 ) = arg max ( c 1 c 2  c r i 1 ) P r i 1 j =1 c j 2 j 1 (5) subject to the condition: P r i 1 j =1 c j 2 j 1 jb z i ( k ) i ( k ) + 1 2 cj : Fur ther more , w e set c r i = 0 when z i ( k ) 0 and set c r i = 1 when z i ( k ) < 0 . This implies that r i = log 2 M i + 1 : Then the data r ate of the channel is giv en b y R = P n i =1 r i (bits/sample) : Our main result is the f ollo wing theorem: Quantiz ed F eedbac k Control of Netw or k Empo w er ment Amm unition with ... (F ang Jin) Evaluation Warning : The document was created with Spire.PDF for Python.
528 ISSN: 1693-6930 Theorem 1: Consider the system (1). Suppose that all the eigen v alues of A + B K lie inside the unit circle . Then, f or an y giv en " 2 (0 ; 1) , there e xist a control la w of the f or m (2), a quantization algor ithm of the f or m (4), and a coding algor ithm of the f or m (5) to stabiliz e the system (1) in the mean square sense (3) if the data r ate of the channel satisfies the f ollo wing condition: R > P i 2 1 2 log 2 2 i " (bits/sample) where := f i 2 f 1 ; 2 ; ; n g : 2 i " > 1 g . Pr oof: Consider the closed-loop system X ( k + 1) = AX ( k ) + B K ^ X ( k ) which is equiv alent to X ( k + 1) = H AH 0 X ( k ) + H B K H 0 ~ X ( k ) : Fur ther more , notice that ~ X ( k + 1) = H ( A + B K ) H 0 ~ X ( k ) : By the definitions abo v e , w e ha v e ^ X ( k ) := H 0 ( ~ X ( k ) + ^ Z ( k )) , Z ( k ) := X ( k ) ~ X ( k ) , ^ Z ( k ) = Z ( k ) V ( k ) , and ~ X ( k ) := H ^ X ( k ) . Thus , it f ollo ws that Z ( k + 1) = X ( k + 1) ~ X ( k + 1) = H AH 0 ( X ( k ) ~ X ( k )) = H AH 0 [( ~ X ( k ) + Z ( k )) ( ~ X ( k ) + ^ Z ( k ))] = H AH 0 V ( k ) : (6) Clear ly , the prediction error Z ( k + 1) is deter mined b y the pre vious quantization error V ( k ) , and is independent of the control signals applied. Notice that X ( k ) = H 0 X ( k ) = H 0 ( ~ X ( k ) + Z ( k )) : Thus , it holds that E k X ( k ) k 2 = E k X ( k ) k 2 = E k ~ X ( k ) k 2 + E k Z ( k ) k 2 + 2 E [ ~ X 0 ( k ) Z ( k )] : (7) By the definition abo v e , w e see that ~ X ( k ) = H ( A + B K ) H 0 ~ X ( k 1) : Fur ther more , it f ollo ws from (6) that Z ( k ) = H AH 0 V ( k 1) : Thus , w e ha v e E [ ~ X 0 ( k ) Z ( k )] = E [ ~ X 0 ( k 1) H ( A + B K ) 0 AH 0 V ( k 1)] = E [( X ( k 1) V ( k 1)) 0 H ( A + B K ) 0 AH 0 V ( k 1)] : (8) Here , X ( k 1) and V ( k 1) are m utually independent r andom v ar iab les . This implies E [ X 0 ( k 1) V ( k 1)] = 0 : (9) Substitute (9) into (8), and obtain E [ ~ X 0 ( k ) Z ( k )] = E [ V 0 ( k 1) H ( A + B K ) 0 AH 0 V ( k 1)] : (10) Thus , substituting (10) into (7), w e ma y obtain E k X ( k ) k 2 = E k ~ X ( k ) k 2 + E k Z ( k ) k 2 2 E [ V 0 ( k 1) H ( A + B K ) 0 AH 0 V ( k 1)] : (11) TELK OMNIKA V ol. 12, No . 3, September 2014 : 525 532 Evaluation Warning : The document was created with Spire.PDF for Python.
TELK OMNIKA ISSN: 1693-6930 529 F or an y giv en v ector X , w e define X := E [ X X 0 ] . It f ollo ws from (6) that E k Z ( k + 1) k 2 = tr [ Z ( k +1) ] = tr [( H AH 0 ) V ( k ) ( H AH 0 ) 0 ] = tr [( H AH 0 ) 0 ( H AH 0 ) V ( k ) ] = tr [( H A 0 AH 0 ) V ( k ) ] = tr [ 2 V ( k ) ] (12) Let Z ( k ) := [ z 1 ( k ) z 2 ( k ) z n ( k )] 0 and V ( k ) := [ v 1 ( k ) v 2 ( k ) v n ( k )] 0 . If there e xists the quanti- zation algor ithm of the f or m (4) such that the f ollo wing condition holds: "E [ z 2 i ( k )] > 2 i E [ v 2 i ( k )] ; ( i = 1 ; 2 ; ; n ) (13) then w e ha v e E [ z 2 i ( k + 1)] < "E [ z 2 i ( k )] ( i = 1 ; 2 ; ; n ) : This means that E [ z 2 i ( k )] < " k E [ z 2 i (0)] = " k E [ x 2 i (0)] ( i = 1 ; 2 ; ; n ) : Thus , it f ollo ws that lim sup k !1 E [ z 2 i ( k )] = 0 ( i = 1 ; 2 ; ; n ) : Namely , lim sup k !1 E k Z ( k ) k 2 = 0 : (14) Clear ly , it f ollo ws from (6) and (14) that lim sup k !1 E k V ( k ) k 2 = 0 : (15) This implies lim sup k !1 E [ V 0 ( k 1) H ( A + B K ) 0 AH 0 V ( k 1)] = 0 : (16) Notice that ~ X ( k + 1) = H ( A + B K ) H 0 ~ X ( k ) = H ( A + B K ) H 0 ~ X ( k ) + H ( A + B K ) H 0 ^ Z ( k ) : It f ollo ws from (14) and (15) that lim sup k !1 E k ^ Z ( k ) k 2 = 0 : Fur ther more , w e kno w that all eigen v alues of A + B K lie inside the unit circle . Thus , it f ollo ws that lim sup k !1 E k ~ X ( k ) k 2 = 0 : (17) Thus , substitute (14), (16), and (17) into (11), and obtain lim sup k !1 E k X ( k ) k 2 = 0 : This means that, the system (1) is asymptotically stabilizab le in the mean square sense (3) if there e xists the quantization algor ithm of the f or m (4) such that the condition (13) holds . By the quantization algor ith m of the f or m (4), w e kno w that the quantization error V ( k ) ma y be small enough to mak e the condition (13) hold if the quantization le v els are large enough. Notice that f or the case with 2 i " < 1 , the condition (13) m ust hold though w e do not quantiz e the corresponding z i ( k ) , and do not tr ansmit its inf or mation to the controller . Thus , in order to mak e the condition (13) hold, w e set M i > i 2 p " ; r i > 1 2 log 2 2 i " Quantiz ed F eedbac k Control of Netw or k Empo w er ment Amm unition with ... (F ang Jin) Evaluation Warning : The document was created with Spire.PDF for Python.
530 ISSN: 1693-6930 when 2 i " > 1 holds . Thus , it f ollo ws that R = P i 2 r i > P i 2 1 2 log 2 2 i " (bits/sample) where := f i 2 f 1 ; 2 ; ; n g : 2 i " > 1 g . Remark 2: Theorem 1 states that, the bit-allocation algor ithm on the basis of not the eigen v alues b ut the singular v alu es of the system matr ix A can still guar ant ee stabilization of the sys t em (1). The par ameter " has an impor tant eff ect on the r ate of con v ergence . F or the case with " = 1 , w e ma y also present a similar argument. Ho w e v er , w e stress that, the system (1) ma y be not asymptotically stabilizab le , b ut be boundab le if the data r ate satisfies the condition: R > P i 2 log 2 j i j (bits/sample) where := f i 2 f 1 ; 2 ; ; n g : j i j > 1 g . If w e set " = 1 and assume that all the singular v alues of the system matr ix A are larger than 1, it f ollo ws from Theorem 1 that R > P n i =1 log 2 j i j = log 2 j det( A ) j (bits/sample) : Namely , our result ma y reduce to the w ell kno w data r ate theorem [9,11]. 4. Numerical Example In this section, w e present a n umer ical e xample f or netw or k empo w er ment amm unition to illustr ate the eff ectiv eness of the bit-allocation algor ithm giv en in our results . Let us con s i der a netw or k ed control system which e v olv es in discrete-time according to X ( t + 1) = 2 4 3 : 4331 17 : 3913 37 : 9582 12 : 4331 32 : 3913 33 : 9582 7 : 4331 17 : 3913 7 : 9582 3 5 X ( t ) + 2 4 1 : 4 1 : 7 2 : 1 3 5 U ( t ) : A control la w is giv en b y K = [11 : 32830 24 : 3046 21 : 9182] 0 . The initial plant state is giv en b y X 0 = [2000 1000 200] 0 . The eigen v alues of the system matr ix A are 7, 7 + 6 i , 7 6 i , and ha v e magnitudes of 7, 9.2195, 9.2195. T o achie v e the minim um bit-r ate needed to stabiliz e the unstab le plant, one ma y find a matr ix H = 2 4 0 : 9464 0 : 8546 0 : 8546 0 : 2983 0 : 4037 0 : 2202 i 0 : 4037 + 0 : 2202 i 0 : 1234 0 : 0499 0 : 236 i 0 : 0499 + 0 : 236 i 3 5 which diagonaliz es A or tr ansf or ms A to a Jordan canonical f or m. Then, b y emplo ying coordinate tr ansf or m, w e define X ( k ) := H X ( k ) ; and quantiz e X ( k ) , encode X ( k ) , and tr ansmit the inf or mation of X ( k ) to the controller o v er a digital comm unication channel. Let X ( k ) := [ x 1 ( k ) x 2 ( k ) x 3 ( k )] 0 . Clear ly , x 2 ( k ) and x 3 ( k ) are comple x v alues , b ut are not comple x conjugates of each other . Thus , each x 2 ( k ) and x 3 ( k ) could not be reconstr ucted from only its real par t or its comple x par t. Then, one has to quantiz e the real and imaginar y par ts of each x 2 ( k ) and x 3 ( k ) in order to guar antee b oundedness of each x i ( k ) . Thus , the minim um bit-r ate needed to stabiliz e the unstab le plant is 19 bits/sample (since the bit r ate m ust be an integer). TELK OMNIKA V ol. 12, No . 3, September 2014 : 525 532 Evaluation Warning : The document was created with Spire.PDF for Python.
TELK OMNIKA ISSN: 1693-6930 531 Figure 1. T r ajector y of plant states . T o reduce the conser v atism, w e find a real matr ix H = 2 4 0 : 8802 0 : 4288 0 : 2034 0 : 4580 0 : 6549 0 : 6011 0 : 1246 0 : 6223 0 : 7728 3 5 which can diagonaliz e A 0 A = H 0 2 H with = diag[0.5477, 15.4175, 65.5362]. It f ollo ws from Theorem 1 that, the minim um bit-r ate needed to stab iliz e the unstab le plant is 11 bits/sample which is same as that in [9], [11], etc. The corresponding sim ulation is obtained and sho wn in Fig.1. Clear ly , the system is stabilizab le . 5. Conc lusion In this paper , w e presented a ne w bit-allocation algor ithm f or the more gener al system ma- tr ix, on which no assumption that there e xists a real tr ansf or mat ion matr ix such that the system matr ix can be tr ansf or med to a diagonal matr ix or a Jordan canonical f or m w as made . Diff erent from the e xisting bit-allocation algor it hms , the algor ithm proposed here w as on the basis of not the eigen v alues b ut the singular v alues of the system matr ix. It w as der iv ed that the bit-allocation algor ithm can guar antee stabilization of the system. The sim ulation results on netw or k empo w er- ment amm unition ha v e illustr ated the eff ectiv eness of the proposed algor ithm. Ref erences [1] K otta H Z, Rantelobo K, T ena S , Klau G. Wireless Sensor Netw or k F or Landslide Monitor- ing in Nusa T enggar a Tim ur . TELK OMNIKA T elecomm unication Computing Electronics and Control . 2011; 9(1):9-18. [2] T umir an C , Nandar S . P o w er Oscillation Damping Control Using Rob ust Coordinated Smar t De vices . TELK OMNIKA T elecomm unication Computing Electronics and Control . 2011; 9(1):65-72. [3] Atia D M, F ahm y F H, Ahmed N M, Dorr ah H T . A Ne w Control and Design of PEM Fuel Cell System P o w ered Diffused Air Aer ation System. TELK OMNIKA T elecomm unication Comput- ing Electronics and Control . 2012; 10(2):291-302. [4] W ong W S , Broc k ett R W . Systems With Finite Comm unication Bandwidth Constr aints II: Stabilization With Limited Inf or mation F eedbac k. IEEE T r ans . A utomat. Control . 1999; 44(5):1049-1053. [5] Baillieul J . F eedbac k Designs F or Controlling De vice Arr a ys With Comm unication Channel Bandwidth Constr aints . in AR O W or kshop on Smar t Str uctures , P ennsylv ania State Univ , A ug. 1999. Quantiz ed F eedbac k Control of Netw or k Empo w er ment Amm unition with ... (F ang Jin) Evaluation Warning : The document was created with Spire.PDF for Python.
532 ISSN: 1693-6930 [6] Baillieul J . F eedbac k Designs in Inf or mation Based Control. in Stochastic Theor y and Control Proceedings of a W or kshop Held in La wrence , Kansas . B . P asik-Duncan, Ed. Ne w Y or k: Spr inger-V er lag, 2001; 35-57. [7] Baillieul J . F eedbac k Coding f or Inf or mation-Based Control: Oper ating Near The Data-Rate Limit. in Proc. 41st IEEE Conf erence on Decision and Control , Las V egas , Ne v ada USA, 2002; 3229-3236. [8] Li K, Baillieul J . Rob ust Quantization F or Digital Finite Comm unication Bandwidth (DFCB) Control. IEEE T r ans . A utomat. Control . 2004; 49(9):1573-1584. [9] Nair G N, Ev ans R J . Stabilizability of Stochastic Linear Systems With Finit e F eedbac k Data Rates . SIAM J . Control Optim. . 2004; 43(2):413-436. [10] Elia N. When Bode Meets Shannon: Control-Or iented F eedbac k Comm unication Schemes . IEEE T r ans . A utomat. Control . 2004; 49(9):1477-1488. [11] T atik onda S , Mitter S K. Control Under Comm unication Constr aints . IEEE T r ans . A utomat. Control . 2004; 49(7):1056-1068. [12] T atik onda S , Sahai A, Mitter S K. Stochastic Linear Control Ov er a Comm unication Channel. IEEE T r ans . A utomat. Control . 2004; 49(9):1549-1561. [13] Liu Q, Y ang G H. Quantiz ed F eedbac k Control F or Netw or k ed Control Systems Under Inf or- mation Limitation. Inf or mation T echnology And Control . 2011; 40(3):218-226. [14] Liu Q. Stabilization of Unmanned Air V ehicles Ov er Wireless Comm unication Channels . TELK OMNIKA Indonesian Jour nal of Electr ical Engineer ing . 2012; 11(7):1701-1708. [15] Liu Q. Coordinated Motion Control of A utonomous and Semiautonomous Mobile Agents . TELK OMNIKA Indonesian Jour nal of Electr ical Engineer ing . 2012; 10(8):1929-1935. [16] Liberz on D , Ne s i c D . Input-T o-State Stabilization of Linear Systems With Quantiz ed State Measurements . IEEE T r ansactions on A utomatic Control . 2007; 52(5):767-781. TELK OMNIKA V ol. 12, No . 3, September 2014 : 525 532 Evaluation Warning : The document was created with Spire.PDF for Python.