CA2225901A1 - Remotely controlled gain control of transceiver used to inter-connect wireless telephones to a broadband network - Google Patents
Remotely controlled gain control of transceiver used to inter-connect wireless telephones to a broadband network Download PDFInfo
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- CA2225901A1 CA2225901A1 CA 2225901 CA2225901A CA2225901A1 CA 2225901 A1 CA2225901 A1 CA 2225901A1 CA 2225901 CA2225901 CA 2225901 CA 2225901 A CA2225901 A CA 2225901A CA 2225901 A1 CA2225901 A1 CA 2225901A1
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- remote transceivers
- gain
- central transceiver
- level
- signals
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/24—Radio transmission systems, i.e. using radiation field for communication between two or more posts
- H04B7/26—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile
- H04B7/2603—Arrangements for wireless physical layer control
- H04B7/2609—Arrangements for range control, e.g. by using remote antennas
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- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Mobile Radio Communication Systems (AREA)
Abstract
Circuitry in central and remote transceivers is disclosed to monitor wireless telephone signal levels and control the settings of gain control circuitry in a plurality of remote transceivers that carry telephony signals between wireless telephones and the central transceiver via a broadband distribution network so that the central transceiver receives telephone signals from all remote transceivers within a given range of signal amplitude.
Description
r~ 4 97 14:11 FRO~I: CA 02225901 l997-l2-24 TLI:613 2~Z 8440 PP~E:~33 p43~6 . IlemDt~Jy Comrol~ Ci~in Con~rol C~ Tr~ v~r r)z~d T~ In~ CannoA W~l~s Tcl--ph~Pff l o A Br~R~d ?~
~MOTEIJY CONTROLLED GAlN CO~TROI
0:~ T~ANSCE~VER USED TO INTER-CO~NEC~T WIRFl F!CS
TELEP~lONES TO ~ BRO~PB~ NI~TWOR~
5 Field ~fthe Invention ~ he present invention relates to wireless telephones and more particularly to appuatus tor centrally controllin~ the operation and settings of gain control circuitry in remote transceiYers that carly tolepl~ y signals bet~een wireles~ telephones and a broad~and 10 distribulion network that carrie~ telcpho~ signals to a telephone network Back~round of the lnvention The prior art leaches the use of existin~ cable îelevision networl; cables to carr~
5 teleph~ny si~nals between a telephone network and remote transceiver sites in defined cells or sectors 'rhe transGeivers are used to establish wireless telephony communication link~ with wirclcss telephones that ale operating withiin ~n ~rea cowred by each remote transceiver. To increase the number of wireless ~t~le~h~ne subscnbers that c~n use the wireless teleph~-ne sys~em it has been suggested to decreasc the size and operational ran~,e of each cell or sector~
20 and to incre~se the num~er of ~ells or sectors required to provide wireless telephone serYic~ to a given uea Havin~ or ~ectors of decreased size penn~ts ~sreater reuse Df the limited number of fiequ~ncy chdnneli ~llocated for wireless selephone service because other ~ells or se~tors l~cated ~t ~ clDser r~n~e can reu~e the s~lme f;equency cl~nr -I for additional calls ~thout ~ignal interference. The advanta~es of reducin~ oell or sector ~ize to increase the call 2S canyin~ capacity of the wireless leleFh~ne network is ofl~et by the requirement for additional remnte transceivers for the additional cells. This offset is n~inimized by 11-ili7il~5 an existin~
broadband distri~ution network to pra~ide the cormnunicationc path ~etween remote transceivers in each of ~he cells or s~ctors and a centr~l tr~scei~vel Th~ b~e transceiver CIE{-2~ 97 14:11 FROM: CA 022i590l l99'7-l2-24 T~ t'~ 32 8~0 PRGE:04 ~326 ~ R~m~el~ Cohlroll~d ~n C~l OJ T~w~i~a U~cd To Ir~ Wu~lc~ Teleph~.ne:~ To A ~d~J ~ch~or~:
station acts as the in~er~ace b~tween the telephone network and the wireless telephone system, ~nd the central transeeiver acts as the wireless telephone system interface with the bro~dband distribl~ion network To carry wireles~ telephony si~nals over ~ broadband distri~ution network, as described above, ~ predetermin~d b4ndwi~th ~n ttle networ~; is typically a~ ca~ed fDr this purpose.
owever, as required7 more bandw~dth m3y be aJlocatcd to c~lry wir~less t~l~rh~ y si~nals.
Tc~ most efficiently use a given bandwidth to c~y ~4~reles~ telephony Sigllal~ bet~een wireless telephones ~ld thc ~ phl~ne network, a ~mbin~tion of ~e~uency and time divis;~n 10 muhiple~in~ is utilized This req~i~es base transc~iver st~tion eq~lipment that acts as the int~ ce with the lelep~ne network and the wireless telephone ~ystem With the base transceiver station equipment is a central trsnsceiver ~RASP), als~ called a Jleadend Interface Clo~verter ~H~C)~ ti-al interfaces ~vith the brordb~ distributiun network ~nd it must fimction with telcphony si~nals in the wide ~equency spectrum of r~di~ freql~ency si~nals on the 15 t~lephone network. ~Ind up lo 1000 ~z over the broetlh~n~ ~istribution network This systom also requires a plurality ol'remote transcei~ers, also called cable micr~ell inl¢grators (CM~s~
or Remote Anterula I~ri~ers (RADs~, in each of the cells or s~ctori that can c~rry m~ny channels of tel~phony sign~ls betw~n the w~rel~s telephone~ and the eentral lranscciYor via the ~r.~h~nd distribution n~twork, ~ithout creatin~s si~snal in~ ren~e with ;he teleph~ny u sign~ls in adjacent cells ~r sectors In addition. ~he remote transceivers (RAD j~ must ~nction with and translate lelephony si~n~l~ in the ~ide i~equency ~pectrums of up to 1000 Mh~ on the broa~ nd dislribution n~twork and between 18SO - l~gO ~Hz for the radio link be~ween ~emote transceiver~ and w~reiess t.,l~hl-l,es 2 5 In a~dition. the relnotely lo~ated transçeiYers ~nd the bros~band distribution network are exposed tO mJmerous a~verse Cf ,1'~ r~ suçh as te~ e~ah~re extremes, whiGh adversely ~ffect the power levels output ifrom the tnnsceivers, ~nd a~ec 105se5 and gains along the br~ad~anll distnibution network. The po~4er levels output ~m the remote transceiv~r~ must DEC-Z~ 97 14:1~ FRO~ CA 02225901 1997-12 24 TO:~13 232 8:1~0 P~(~E:E15 1~43~ - Ren~ely C4n~ C~ol Of T~Dci~ wJ To Inl4r~cnn~ W~b~ I elcph~r~ T4 A ~adb~l~ N~lwark be constantly moni~ored and ~ sted to cnmpensate f~r these adverse conditions ln addition~
~ueh remote transceivers need to con",~ e not only for network variations between each rem~te tr~ns~ei~er and lhe ~ traJ trulsceiver, but al~ for the temporat variati~ns in the v~rious network links between Ihe remole ~nd central tr~nsceivers Summary s~f the In~/enti~n Thus, there is a need in the an for tr~nsceivers or RAD~ for use in such a wireless telephony system to carry telephony sign~ls between a telephone network and w~reless 10 tel~phol~es ~ia a broadb~nd distributiotl net~o~k alon~ which are ren~otely distributed a plurality o~the transcei~ers The gain ofthese remote trhJ~ ers will be adjust~d ~y the central transceiver which is mon;itonn~ the pow~r levcl of signa]s recei~ed firom euch remote transceiver so that sicnals reeeived from the wireless telephones ure at ~ consistent level, that is wi~hin a relatively narrow lccepta~ility raulge, when inpllt to the central lransceiver lS
The abo~/e described need in the wireless teleph~ne system prior art is s~ti6fied by the present inventiun. A ~mal~ transceiver is provided which is u~d in a wirelsss tel~phone system of the t~e briefly described above These remotely located tran~ceivers ue used to cany telephony si~nal~ between wireless telephones and central transceivers via a broadband 2 ~ di~tribution network, such as ~C~ fiber OptlC c~blel or co~xial cable, on which the remote transceivers are hun~ ~nd t~ which they are connected Thus, these remote transceivers are remotcly l.~cat~d and ~linullate tlle n~l for prior r~ an~enna to~Yers ~o carry telephony signals between wi~eless telephones and central transceivers Each remote transceiver has ~ain ~ontrol citcuitry by which the ~ n ~ Ihe remote transceivers can be adjusted by the centr~l tr~nsceiver 2 5 which is monitoring the power level of a gain tone signal received from each relnote u~.3~iver. This is dnne sO that the signal level oft~ ny si~n~ls from the wireless telephones and appeanng at the input of Ihe cent¢al l~.,scL;~er are at a ~onsistent level th~t is ~thin a relatively narrow r4nge a~ceptable to the central transceiYer.
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Descnption of the Dr~wing The invention will be better understood upon readinl3 the fo]lowin~ Petailed l:)e~cr.~tion in conj~lnetior ~4ith the drawing in which:
S
~ igure 1 is a bl~k diagr~n of a wireless telephony sy~teln integrated ~ith an eY~ lpl~ybrosdbu~ddistnbu~ionnetwork.
Figure 2 is a simplified blo~k dia~ram of a ren~ote tr~nseeiver u~e~ w,ith the wireless 10 lelephony system, Figure 3 is a det~iled block diagranl of the portion ~f a remote tr~nsceiver that transmits telephony si~nals received ~on~ wireless teleph- n~ and sent Yia a bro~dh~nd dlstribution network to a central transceiver~ and the remote transceiver has gain control 15 circuitry that i~ rernotely controlled by the central transceiver; and Figure 4 i~ a block ~ia~lram of a portion of ~ central transceiver that is used to monitor Ihe si~nal g~in of ~ gain tone recei~ed from each of ~ plurality of remote transceivers ~ong with telephony signals, and send control sign~ls to each remote tr~nscei~er to adjust its signal 2 0 g8in Det~iled ~ riptinn In the dra~in~ and the folio~ det~iled description, all ~lements are ~c~i~ned three 2 5 digit reference numbers rhe first digit ~f each reference number indicates in which fi~ure of the drawin~ an element is loeated The second and third digits of each, efe ce number indicate s~ecific elements If the same element appeus in more than one figure of the drawin~.
the second and t~urd digits rema~n the ~ame ~nd only the first digit chanyes to iE~diçate the ~r~ '~ - ~1~7 ~ bl3 2i~ 8~4~ P~I~E:07 DEl~-24 g~l' 14:l2 FRO1'1: CA Oi225901 1997-12-24 D4326 ~ eiy l~ollcd ~;b~n C~rol Of T~iva Ibd To I~ W~rcleb~ pho~ T~ db~nd ~i ~tW4~A
figure of the drawing in which th~ element is located As used herein the terrn "~elephony ~i~n~ls" incl~de~ voice, d4ta, f~x and any oth~r types of si~r~als that are sent over a telepholle net~ork now or in the fi~ re. Throughout the ~i~res and lhe followin~ descripti~nl refe~ence is m~de f~r one exs~le, [o a combined band pass filler ~nd ~snplifier 3~5a. There ~re a S nu~nber of other such c~mbined band p~ss fiJterD and ~mplifiers. They are ~hown and refereTl~d this way for e~se of pre~entation only. In reality they are eacb a discrete, separate filter the out~ut of which is input to a n ~"~rlifi~t ln Fi~ure 1 is sho~n ~ simple block dia~raJn of an ~ mF!A~ broadband distnbution10 network 112 integrated with ~ wireless tcle~honc system whicb includes a plurality of remotely 1nc~ted trans~eivers known aS Remote Antenn~ Drivers ~RADs~ . Ther~ are differ~nt types of broadb~nd distri~ution networks in use that m~y be utilized ~4ith the pre~ent invention Such networks may utili~e coa~i~t c~ble ~nd fib~r optic ~able rn thc embodiment of the invention diselos~d herein a conventional hybrid fiber ~oax~sl (~FC~ cable distribution s~slem 15 is utilized o~the type u~ed for cable ~elevision distri~ution nel~orlcs~ but other types or combin~tions of broadband distribution network~ may also be utilked Electrical power is distributed ~lon~ ~road~and di~tribution network 112 to power line amplifiers (not shown) of the btoadband distribution network This electri~al power source ar alternate power sources, are used to provide power to RA~s 11~ a-i ~o In~e~rated with ~roadband distribution network 112 i~ a wireless telephony system in which the presen~ invelltion is ~Itili~ed. One j-lch wireless telephony sy5tem is taught in U S
Pat~nt application 081~5,175, filed Au~ 1, 1996, and entitled "Appara~us And l~,~ethod For Distnbuting Wir~le~s (~ommumcati~ns Si~nalj To ~omote Cellular Antelulas". The tclcphon~
5 system di~closed herein and shown in Fi~ure 1, in~ s a base l~an~ceiver station (HTS) I 1 S
which is wnnected tC) ~I telephone system I 16 Base transceiver xtation 1 15 i~ also c~nne~t~d to a Remote ~ntenna Signal Proces~or (R~SP) I ~ 7 ~bhich is the interface to a bro~dband distribution network 1 12 Telephony si~nals to be sent between telephone sy~ern 1 16 and Z4 g7 1~: 13 FROI~I: CA 0 2 2 2 5 9 0 1 19 9 7 - 12 - 2 4 Pi~GE: 08 ~431~ - p.crnolcl y Cor~l loA4 ~un C~l ~ Us~d T~ W irt l~ l tlcph~ l o A E~ro~ ctwDr.~
wirel~ss tel~Fhon~s I 1~ ~re carried via t~ro~d~on~1 network 1 12 using RASP I 17 an~ Remote Antenn~ Drivers (RAD) 118.
A~ is l;nown in the prior art, in~ n~s the l~bo~/e ~ited pnor art patent applic~ior~ one 5 or more ~equency bands or ch~ ls ofthe braadhand distrlbutic~n network 112 ~re aeci6ned to c~m telephony corn~ n ~h~iOrlc and control signals between telephone system 116 and ~ireless telephones I 1~ Telephony sign~ls originating ~om telephone system I ]6 are ,.utted ~y RASP 117, in *eq~ency division mu~ d~e furmat, via bro~d~nd network 112 to ~ plur~lity of remote antenna dnvers (~ADs~ i which are connected to broad~and 10 distribution network 1 1~ Te~ephony signal~ ori~in~ti~ ~t wireless tPleph~n~s I 1~ are ~equency mul~iplexed to~t~th~r by RADs 118 ~-i and ~re transmitted alon~ with contrvl and ~in tone signals via ~roadband net~ork 11~ to ItASP 1 17, al1d Iher~e to base trans~ er station 1 I S and telephone syssem 3 In ba~ ans~.~er station 115 there are a plurality oftranscei~er modules (not shown~
as is known in the wirele~ telephony an, e~ch of ~hich opcrates ~t a single channel frequen~y ~t a timc, and which can handle ~ predel~fu~."ed m~Y~ m number of telephone calls ~om wireless telephones In the wireless telephone system described and cl~imed her~in, ~he frequen~y ~h~t the RADs I 18 are as~igned to operate at must c~rrespond to the operating 2 0 fre4uency of the assigned BTS transceiwr mod~le If ~ particul~r R~D 1 18 is re-assigned tO
fiunction with a di~erent transceiver module ~ithin ~ase transceiver station 11~, ~ir~uit se~tings wilhin ~he particular RA~ must ~e ~ ng~d to fi~nclion wil~ the dit~rent transceiver module. Irl the wircless telephDny art, transceiYer modules in Iht b~se transceiver station are also referred to ~s ch~nnel cArd modulcs and radio mc~dul~6.
When wireless telephony traffic in a first ~ector or ceD incre~se~ to the point where adequate ser~ ice i5 not provided to wireless telephone subscribers in the first sector or celL lil~e during rush hour traffic on a hi~hw~y~ in accordance with the tea~kin~ of the present invention 9 ~7 14 13 FRI~ F3~ 7 I~ bl3 232 ~ P~GE: 0~E~-2 . . CA 0222~901 1997-12-24 D~132~ Remu~ely L'onuollcd ~}~u C'~nlrol O~Tr~ iVa Uccd To Inlcr~q~ ~'uele~ lcl~phne~ To A i~ir~dbu~d Ne~
the wireless telephone Syslem may be remotely reconfigured by RASP 117 to reassign one ~r more RADj 1 18 from one or m~re nearby ~ectors or cells, where those ~A~s I I g have overl~ppin~ signAl cov~ra~e wi~h t~e fir~t sector or c~lL ~o handle the ex~ess wireless telephony traffi~ in the first sector cell.
ln Fi~ure I ar~ shown three rows of R~Ps I 18. Typically a number of R~I)s 1 18 are spaced alon~ and connected t~, bro~dband dis~ ution network 112 to pro~id~ overla,ppin~
sign~l transm~sion and reception covera~e for the entire wireless teleph~ne system. Some of the RADs 11~ are physically l~eated ne~r the bounJ~ry between tw4 or more cells or sectors 1 n and, ~epe~ on the frequency of operation th~ are set to, can be used to handle ui~eless telephony traffic in o~e or more of the sectors or ceils Let us ~ssume lhi~t RADs I 1~ ~,h~i in the bottom rov~ are physica]ly lac~ted along bro.l lb~nd distri~ution system I 1~ and ~re configured to handle wireless telepholly tr~ffic in a first ~ctor tha~ includes a highway. I:~unn6 early mornin~ and late afternoon every work day there is nl~h hour traffic that creates pe~k 15 wireless telephone trdffic that c~useY UqR ~c~ptable sen~ce delays in the first sector. Let us also a~s~me that the RAPs 1 1 ~d,e,f in the middle row in Fi~ure I ~re confi~ured ~nd locat~d to handle wuele~s telephone traf~ic in a se~ond. adj~cent ~eetor but they ea~h have an ~rea of signal operation that overlapj the hi~h~ay in the fir~t sector O One or more of RADs l 18 d,e,f may be dynan~cally reassi~ned by R~SP ] 17 to the first sector lo h~ndle the increased t~lephony traffic oniginating ~om the highway ln addition, ~5 necesja~, addition~ ASP 117 ~hannrIc may be a~ igne~1 ~nd additional modules in base tran$~eiver station 1 15 may be assigned to handle the excess wireless teleph~ny traffic firom the first ~e~tor To do this RASP I 1 ? sends control ~i~n~ls to the ~elected remote RADs d,e,f which ~ill cause the frequenGy at which they operate to be changed lo mat~h the frequency of RADS 1 18 g,h i that are nonnally as~ d to handle wirele~s telephone traffic in the first sector ~t the end of the peak traffic per~oJ RASP I 17 may jend control siynaJs to the previously re~llo~ted ones of RADs 1 I 8 d,e,f to C~ jSe lhe frequency at which they operate CIEC-ZY 97 14:14 FROM: CA 0222590l l997-l2-24 bl3 _3~ ~4413 Pf~GE:10 1~43~ . Rcmah~ C~-~llc~ 13D~J) ~ ol (~rl'n~i~a U~ To ~ l Wucles~ ~I'dcph~nc~ T4 A ~r~dbu~ ~e~ rl~
b3ck 10 th~ir original settinys ~ they are reassigned to handle wireless telephony traffic in the second sector ~lo~-ever, the r~-assignrnent may be permanent dependin~ on t~affic patterns encollntered Typically ~here are a nurnher of R~s 1 18 ~-i spaced ~long snd connected to broa~l-~ntl distnbution network 112 to pra~ide overlappin~, si~nal trAnsrnission and reception coverage fior the entire w~reless telephone system Each RA~ 1 18 has anter~n~s 120, 121, 12 used to transmit to and receive jiynals from remote wireless telephones 1 19. Anlenna 120 is used to transmit telephon~! signals to wireless telephones 1 l~, while antennas 12i and 1'2 are used to receive lelephony signals firom ~ireless t~l~,nl~nes 119. ~ultenna 121 is called the pnnnary antenna, and ant~nna 1~ is called the diversily ~nteMa Antennas 121 ~and 1~2 are physically spaced and c~opera~e to minJrn~ze signal fading and ther~by provide continuous si~nal r~ception from wirelL~s telephones 1 19.
In Fi~ure 2 is shown ~ ~eneral block dia~ram of Remote Am~nna l~riv~r (RAD) ~18 The~e is a first circuit 20~ of ~AD 218 that receive~ telephony 5i~nals or~inatine at telephone system 1 16 2nd carr~ed ~ia R~~SP 117, ~ro~dl~and network 212, and tra~s~ts them via antenna 220 of a RAD 1 18 to a remote wireless telephone I 1 g (not shown~. There is ~lso a sec~nd circuit 209 of R~D 218, that is shown in det~il in Figure 3, that receives ~eiephony 2 0 si~nals origin~lin~ at a ~ireless teleph~ne I 19, and t~n5mits them via broadband distribution netwo~L 21~ lO RASP I l 7~ ~nd ~hen~ lo ba~e t~ er ststion ~ nd telephone system~16.
RAl) circults 208 and ~0~ are connected to and controlled by a microprocessor 210.
2 5 Frequency multiplexed with the telephony signals calT.ied beIween ~ASP 1 17 and each of RADs 218 a-i are signals for controllin~ ~ain control circuitry in each of remote RAD~ ~18 a-i in a-~ordance with the teac;hing ofthe present invention The ~ain control circuitry in RAD
c}rcuit 20~ , alle~ by RA~SP 1 1~ to adjust its output signal level so th~l the power level I~EC-i~4 97 14:14 FRQM: CA oi22S9ol lgF'97-l2-24 Tn~ 32 ~1~4~3 Pfll~E:
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of telephony si~nals inpul to R~SP 1 17 is wilhin a relatively narrow ran~e acceptable to RASP
1 17. This is rrpeated for all rernotely loc~ted ~ADs 11~ a-i distnbuIed along and ~o~ulected ~o the ~roadband distributian network 21~.
Microprocessor ~10 sends a conuol aignal via leBd ACi~ to RAD circuit ~09 which causes the output of an ~scill~tor 342 ~aïn tone si~ , w~th known si~nal le~el, t~ be ~-on~bined with any teleph~ny signal~ and transmitled to RASP 117 ~ria bro~band di6tribution network 112.
The gain tone siKnal level is of a low a~rlit~de that does not interfere with Ihe elephony si~snals with ~hich it is mixed, bllt is s0pasated from the telephony si~nals at ~ASP
1 17 RA SP 1 17 lnalv~es the amplitude of the received g~qin tone signal~ which will reflect gains and losses in ~AD 218 and brc~hand dislribution network 212, hS part of a ~etennination whether or nut t~ chan~e attenu~tor 330a, 330b and 336 settin~s in RA~ 21 This operation is repe~ted fur each remotely located RA~ 21~ so that lhe power level of telephony signals input to RASP 117 is ~vithin a relatively narrow range acceptable to EtASP
117.
~fter processinR the ~in tone signal received alon~ with telepllony signals ~orn each 2 0 of the RP~Os ~18 t~ determine Jf the si~ l le~rels are too 3Ow or too high, RASP I 1~ sends 4din t-)ne cc)ntr~l ~ignal back lO e~eh RAD 218 in which the siKnal level has to be ~dju~ted Thl~ control sianal is received by m~croprocess~r 210 on lead~ CTRL ~om RA~ ~ircuit ~08 Micrnproc~ss~r 210 re~ponds to the gain tone control si~nal re~eived ~om R~SP 1 17 ~ end an AC;C a~justment si~nal vi~ leads AGC ~o ~D circuits 208 ~nd 20g In R~I) circuit ~0 2 5 the A~ adjustment signal results in changes being made to attenuators in circ~it 20~, ~s described in ~reater det~l with referenee to Figure 3, to adjust the signal level of rhe telephony signal~ lhar are received by RASP 117. Thi~ ad~ menl a~count~ for losses And y~ins nnt only in RA~ 218, but ~1so in bro~b~nd distribution ne~w~rk 212 ln this manner the power level GEC-Z~ 97 14:15 FROI~l: CA 022i590l l997-l2-24 TO:~13 232 844~3 P~GE:l~
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of ~i~nais received by l~SP 117 from all RADs 218 s-i are within a relatively narro~v range n~rt ~~1~ t~ SP 1 1 7 RAP 218 may also receive an intetroga~ion control signal ~t sny time from RASP 117 u~hich ca~es rr~croprocessor 210 to send information about R~) 21~ back t~ R~SP I 17 This information includes the s~tings of attenuator pads 330a~ 330b and 336, the semperature at which each RA;~ 218 is operatin~, and other information The inf~rmation list~d in the last sentence i5 used by RASP 1 17 in n~aking decision6 re~arding controllin~ the si~snal level of each RA~ 218.
In Figure 3 is shown a detailed block diagram of RAD circuit 30~ within novel, Rern~te Anterma Driver (RA~) 1 181 ? 11~ that carries telephony signals frorn a wireless telephone 1 19, via broadband distribution network 1 12, to RASP 117 and b~se tr~nsceiver st~ti4n 11~ This cireuit is shown as ~AD circuit 20~ in FiE~re 2.
Briefly, pnmary receive antenna 3~1 is connected to a first por.~tion of the ~ uitry in Fi~ur~ 3, and th~t circuitry is identical to a second porti~n of lhe circuit~y that is connected to diversity receiYc ~ntenr~a 3~2. The telephony si~nals received by ~oth antemla~ 321 ~nd 3'~2 from a wireless tel~phone 1 ] 9 (not shown in Fi~ure 3) are initiall~ processed in puallel~ then 2 0 the two si~nals are frequency multiplexed together and are both returned via broA~b~n~
distribution network 1 12 tO r~m~te RASP I 1~. This operAtion is deseribed in the f~llowinR
puaEraphs.
Telephony sign~ls from ~ wireless t~l~p~onc 1 19 (not shown~ are received by pnmary receive anteMa 321 These si~nal~ are ~nput to an isolator 323a which isolates antenna 321 from RA~ circuit 309 The t~l~phnny si~,n~l is then input to directi~nal coupler 324a that has a ~econd si4nal input thereto firom power di~ider 34~ which is the ~forelnentioned low level, gain tone si~nal that is u~d for g~in control purposes in accord~nce with ~he present inventinn ClEC-i~4 ~7 14:15 FRO~1: CA 0222S90l l997-l2-24 TO:61~ 23~ 10 PHGE:13 D~13~ - Rcm~41y C~lle~ Giin C~,lr~l OrTs~L~ei~,a U~d ~o Inm~Yu~ w~ b Tcl~hc~ To A ~o~db;lnd N~twor~
liain Tone Oscillator 342 is controlled al its input 342a by nucroprocessor 210 whieh is responsive to ~ontrol signals ~om ~SP 1 17. The analo~ ~ain tone si~nal O-ltpUt from ~ain tone oscillator ~42 is at a known a~nplitude and is m~xed with the telephony signal wh~ch is a digit~ pread spectmm format that is ~eli known in the art. lt is this gain tone signal thal is 5 de~ected at RASP 117, processed and used to make a decision to change lhe settings of attenuators 330a, 330~ and 3~.
The telephony signdl received ~om rem~e w~ireless telephone 1 19 and the low level ~ain lone sign~l are applied via directional coupler 324a to a com~ined b~nd p~ss filter and 10 amplifier 325a The ~ ni~ls are amplified and extr~ncous ~ign~ls ~re filt~d ~om the received ~eleph~ny si~nal.
The amplifi~d and fil~ered telephony and gain tone si~nzls are then input to mixer 326a which is the first of two heterodyning stage~ u5ed to ~nven the carrier ~equency of the 15 t~leF~hr~ y si~n~l tu tb~ ~ele~t0d cArrier firequency for tr~n~ n over brc~hqnrl distnbution network 1 12 to Rern~te Anlenna Signal Processor (RASP~ I 17, shown in Figure 1 I~,lixer 326a Al~o has inpl~t thereto a signal ~om local o~cillator 32 î. The first heterodyning signal ~om lo~al oscillator 32? is ~nput to power di~der 3~8 which applies the si~nal ~orn local oscill~tor 327 to both mixers 326a ~nd 326b while p-ovidin~ isol~tion between these tw~
2 0 nuxer~.
The opera~ion of m~xer 326a results in n~ tiple frequenci~s being output ~om theniixer as is known in the art. All the~e signals are input to nurow pass ~and SAW filter and ~mplifier 329a which selects only the dcsired ~quency carrier modulated by the eain lone and 25 telephony Sigllal5 created by nuxe~ 3~6a, and amplifies same.
The trequency xhifled ~rier ~ d~'oted by lhe tel~pl~ony signal is then inpul to step ~ttP~ or 330a which is used to adjust the gain level of the signal in onc ~~~f d~ steps as p~rt CIEC-~4 97 1!1:15 FROM: CA 0222590l 997-l2-24 ~~ ~ 32 84~3 Pf~iE:14 D~32~ R~a~d~ odG~ nuolofT~iv~u~d~ wu~b55lelc~ ~sloA~o~ n4l~e1w4rlL
of the imple"~cn-ation of the pre~ent invention. The ~n~unt of ~tte ~ l~ion provided by step attPn~ or 3 30a is controlled by ~ binary wor~ at its control input 3 31 a ~rom microprocessor 210 Microproce~sor ~10 controls the settin~6 of ~tep ~nenu~o-s 330a. 33ûb and 336 respon~ive to the AGC ~ain con~rol signals received from ~SP 117 as previously descnbed.
S This assuJes that the power level of all teleph~ny signals r~ceivéd by RASP 117 from oll RA~s 218 A-i are w~thin the rel~tively narTow ran~e ar,c e~ ~P~ie ta RASP l l 7 The gain tone and leJephony si~nals oulput ~om step attenu~tor 330a are input tomi~er 33~a along with ~ fixed frequency s om local o~ or 333a Mixer 33Za is the 10 secDnd ofthe aforementioned tw~ heterodyning sta~es However, the ~equency of local os(~ At~r 333B iS different from the frequency of loc~l oscillator 333b l'he result is that the ~rrier frequency of the telephon)~ signal output ~om n-ixer 332a is different than the carrier frequeney ~utput from mixer ~32b l 5 The lelephony signals received by prirllaly antcnn~ 321 ~nd divorsi~y ~nt~nna 322, each now at ~ different carrier frequeney, ~nd the ~ain tone si~nal combined therewith, are c~mbined into one composite signal by co~nt r-- 334. The colnbined signals are first ~Itered by band pass filter and ~mplifier 3~ and then input to step ~ttenu~tor 336 to ~ive a fin31 adj-~stment to the ~i~nal level of these combined signals Similar to the op~ration of the ~0 previously des~r~bed step attenuators, this digit~ly controlled atte~uator 33~ is set by microprocessor 2 l 0 r~sponsiYe to a ~ain contr~l signal received from remote RASP 112 as part of the novel ~,ain control operation The freqllency ml~lt~ x~d telephony signals o~tput ~m step atte~ tor 336 are input 25 to si~n~l combiner 3~? which has a second input fron~ control ~i~nal oscillator 338. The ~requency of Gontrul signal oscill~tor 338 is controlled by B bin~ry sigr~l oll control leads 338a fronl n~icroprocessor ~10 tO set the ~equency of the ~scillato~ RASP 1 1~ is the ori~in ~om which a conlrol si~nal is received to set ~he frequency o~control signal oseillator 338 The EC-2~ ~7 14:1~ F~0~ 0~ 5-Z167 TO:~13 232 8~4~ P~E-15 ~6 - R~ C~oll~ Ouin C~l ~T~I~rU~dT~l~C~w~'~h~Tol~h~TdA~b~d~wk frequency chosen is tO fall withln Ihe b~nd of frequ~nries used for the telephony si~nals received via the prirnary and the diversity ante-ulas Pesror~ e lo different control si~nals received ~om RASP 117, microprocesso~ 210S (FiE~ure 2) sends signals on control inputs 338a. T} ese nucr~processor 210 signals cause contr~l si~nal oscillator 3~8 to produce ~n info~naticln ~ignal. The inforrnation sienal indicates ~arious inforn~atlon about ~ 218, but particul~rly inel~.di~e the settin~s of step anenllato~s 330a, 330b and 336, to RASP 117 as part ofthe novel giin control operation. RASP 117 uses ~his information tO l~oep an upd~t~d status regar.li~ each of the RAD61 18 a-i The output ~nm comhiner 337 now has m~l.tiple teiephony and gain tone si6nals fJequency multiplexed to be re~umed via bro~ d network 112 ~o RASP 117. The signals are the telephony si~nali rçceived by ~ennas 321 and 322, the gJin tone si~ln~ sed ~s part of the present invention, and ~he system information ~i~nal output frorn control si~nal oscill?tor 15 33B This 1;equency mllkiple~ed signal output ~om comt,.j~r 337 is inpLlt to band pass filter and amplifier 33~ ta amp}if~ the signal and to remove any exlr~ne~us si~nals befc~re the si~nal is ~ pled to bro~d~and distributi~n network 112 and sent to RASP I 17 for proee~cin~ In addiIion~ per tt~e teachin~ of the present invention, the signal power level of the telephony 5i~11is such that when i~ is re,~eived at ~SP 117 il is within the relatiYely narrow ranBe O acceytable to RASP 1 17 Iransfor~ner ~nd coupler 340 is used to ~ouple the frequency multiplexed si~nalsdescri~ed in the l~s~ para~raph to broadband distriblnion network 112 The tlansforrner i~ an impedrnce rnatchin~ r~sfomler ha~ring 50 otun pnmary and 75 ohm secondary windin~s 5 When broa~b~nd distrib~tion network 1 1 ~ uses c~acial cable, the secondary winding of transformer 340 is wire~l in ~ries w~th the center conductor ofthe v~deo distr~buti~n coa~ial cable As previously descnbed, RAI:~ ~18 han~ s from the couual cabling of the broadband [~EC-24 97 l4:lo FRCIM: CA 0222 5 90 1 1997-12-24 Tl~:bl-3 ,32 8~40 P~GE:lb P43~6 - R~m~ ConUoll~ /:3~ C~ntrol C~ cr U~d To l~on~ Wir~lc~ r.l.ph~ 1 O A ~ nd Nctwa~k distrib~tion net~40rk 112 to ~ch it is COMe~ted. In other appiicd~ions~ such ~s with fiber opti¢ cable, other well known frequency conversion and si~nal e,ollplinQ techniques are used.
In Fi~ure 4 is shown a block cliagram of the circuitry in RASP 1 17 th~t is used ~o 5 monitor the ~ain tone m~xed w~th teleph~ny and conlrol signAI$ received by R~SP 117 from all RA~ I la a~ bro~b~nd distnbuti~n network 112 There are three inpuIs shown to RF
swit&h 410, desl~ ~ed A, E~ and C Each of these inputs is connecte~l to receive si~nsls from RA~s I 18 oll one se~tor of broadband distribulion network I 12 All RADs I l B on one seclor carr~r telephony si~~nals ar ~I ffrsl camer fiequency Thus, input A will receive tolephony si~nals 10 that have ~ first carrier firequ~ncy, input E~ will r~cei~e teleph~ny si~nals that ha~e a secon~
carrier ~equency, and input C will ~ceive telephony si~nal~ that h~e a third carrier fre4uency ThLIs, with reference to Figure I as ~n example, RA~s 1 18 a-c may all be on one sector and their car~ier signal i~ connecte~ to input A of the circuit in Figure 4, R~Ds 1 18 d-f may all be on ~ second seetor Bnd their ~arr~er signal is connected to input E~ of the circuit in Figure 4, and 5 RADs I 1~ i may aîl be on a lhird seGtor and their carrier signal ls connecteJ t~ input ~ of lhe circ~it in Figure 4 In addition. all the RADs 118 in each sector can simultaneously huidle multiple calls and additional sec~or~ are defined to handle ~diti~nal traffic. If additional wireless telephony traffic must be handl~d, and m~re than three sectors are required, an additional R~SP 1 17 must be plovid~d, and some R~s 1 18 mu&t be re-allocated ~o fùnction o with the addition~ SP I 17 To p~ovide ~i~nals to the ~, B and C inputs, RASP CilCUit 208 has receiver circ-Jit~y c~lMecte~ to each of the three inputs that re~eives telephony and control si~nals transmmed o~ver br~a~b~nd distr~buti~n netw~rk 112 fiom RADs 11~. The re~eiver circuits ~re not 2 5 shown, buI each c~mprises ~n input filter followed by a Si~ llhl divider that applies ~ portion of t~e received siundl lo th~ A, B and C inputs uf the R~SP 117 circuit sh~wn in Figure 4 [~EC-24 ~7 1~:17 FF~0~1: CA 0222590l-l997-l2-24 TCI:~13 ~2 8'~413 P~IGE:17 P43~6 - R~no~ C uluollcd Ci~in CMItral 1~ Trsn~ci vn Li~led Tt~ Imcr~ll,ccl Wuele~ Telq~h~ A E~ro~db~ ~el~t~
Switeh 410 is an RF s~t~h that i5 periodically operated by microproces60r 418 toconnect indi~idusl ones of inputs A, ~ and C to the remainder of the circuitry in Figure 4.
Thus, the poltion ~f circuitry p~st ~witch 410 has input theretol on an indiv~dual basis, the rnulliplexed telephuny si~nals ~om all }~Ds 118 within a ~ector to which it is connected at each mornent in time The telephony si~nal froln each RAD 1 I R has ~ spread spectn rn~
digicized t~310phony 6~nal and the an~ ain tane 6i~na]. The received c~mposite signal frorn all RADs 1 18 within a sector is first amplified by P~nrlifier 411 an~i then input to rn~xer 41'~
alon~ with the o~tput firom IDC~I ~scill~tnr 413. The stuldard heterodyning process of mixer 41~ o produces a number of spurio~ls si~nals. The output of mixe~ ~t 12 ;6 input tD IOW pass ? ~ filter 414 ct~ red around the gain tona which filter6 out most ofthe jpread spectmm signal and the spunou~ si~nals ~o~ ~h~ mixin~ process. This increases the rel~tivo level of the ~a~n tone received from each RAD 1 18 with resp~ct to the ren~oinin~ ener~ of the telephony signal. The resultant ii~nal i5 then ~mrlified at amplifier 415 and input to analog to di~ital eonverter 4~ ~ to chang~ the remain~ng sien~l to a digital signal which is input to digital ~i~nal process<~r 417 for filreher p~oce~ing. The fi~rther p. OC~ 3 thal is performed by Jigital si~nal p~ocessor 417 in dl~ital fonn are the same step~ that have jusl been described for ~he analog ci.euits in Figl~re 4 The digital si~nal that i~ inpl~t to digit~l signal processor 417 is ~igitally heterodyned and low pasj fillered to get ~id of moro, but not all of the r~ in~ telephony 5i~nal. The re~ult is that the ~in lone signal n~ has a 30 dB ~un with rcspect to the O t~lephony si~nal, as compared to the ini~ial p~wer ratios ~enerated by the RADs 118 The ~in tone signal ~om the R~Ds 118 in a soctor is processed ~y microprocessor ~18 and its signal lev~] is compared a~a~nst a st~ndr ~ ~ignal level. ~f the amplitude of the ~~ain tone signal is toQ 10-4~ mi~:roprocessl~r 418 causes ~ ~ain control si~nal to be sent b~ck over 2 5 distr~bution n~tworl~ 1 12 ta the panicular RAD 118 Ihat has the too lo~ gain tor~e This control si~n~l has an address pre-fixed thereto which causes nnly the particular R~ 118 to receive The gain tone conttol signal. Microprocessor ql~ (Figure ~) in the partiGular RAD ] 1 responds to the gain tone con~rol signal and causes a signa1 to ~e output on lead ~GC to [~EC-2497 14:17 FROI'l: CA o222~905 ~9197 12 24 TO:61;~ 232 ~3'14E~ PfiGE: 18 P432~ Ron~tely Coltu~liod O~ Tr~civa ~IR~ To Im4r~ne~:t w~ Telepw~eY To A 13r~n~ N~two~
circuit 20~ (Figure 3) The AGC si~nal is applied to the digital control inputs of step attenuators 330a. 3~b and 336 and causes the attetl~3tion they insert in~o the circuit to be decreased The effect is to i~-cr~asc the power level of the telephony signals ~nd ~ain tone frorn ~ain tone Oscillalor 34~ that i~ combined with the tel~pho~y si~nal and receiYe¢l by th~
CuCult in Fi~ure 4 lf the amplitude of Ihe gain tone is too high microprocessor 418 causes a gain control ~i~n~l to be sent ~ack over distribution net~;ork 11~ to the partic~ r RA~ that ha~ the too high ~ain tone. This gain control si~nal has an ~ddress pre~fixed theret~ which c~uses only the O particular RAD I 18 to receive the 8ain control sign~l. Micr~proc~ssor ~10 (Figure ~) in the particular R~l) 1 18 responds to ~he gain control 6i~nal and causes a si~ndl ln be output on lead AGC to cireuit 20~ (Figure 3) The AGC signal is spplied IO the digital c~ntr~l inputs of step attenuators 3~0~ 0~ and 336 and c~uses the ~ttenuation they insert into the circult to ~e incre~sed The effect is to decrease the power level of the telephony si~nal and ~ain tnn~
1~ transrnitt~d over bro~dband distribution network 112 to R~SP I 17 including the circuit shou~
m Flgure 4 If ~he ~,ain tone si~nal level received and analyzed by the RASP 117 circuil in Fi~ure ~
is eorrect, no ~ain control ~ignals are sent to the pa~ticular RAD 118 to modify tbe setting3 of 2 0 the step anen~ators ~30a, 33~b and 336. As previously descnibed, RAD 1 18 r~ports the ~ettings of its attenuators alld other cir~uits to RASP 11~ using c~ntrol signal oscillator 338.
While what has been dcsc, il~ed hereinabove i8 the preferred embodiment of the ~n control oper~tion oYer a broadband distribl~tion network, it can bc under5tood that numerous 2 5 ch~~,eg m~y ~e ~nade lo the gain control ~ircuilry in RA~ 21~ and RASP I 17 by tho~ skilled in Ihe art with~ut departing from the scope of the invention
~MOTEIJY CONTROLLED GAlN CO~TROI
0:~ T~ANSCE~VER USED TO INTER-CO~NEC~T WIRFl F!CS
TELEP~lONES TO ~ BRO~PB~ NI~TWOR~
5 Field ~fthe Invention ~ he present invention relates to wireless telephones and more particularly to appuatus tor centrally controllin~ the operation and settings of gain control circuitry in remote transceiYers that carly tolepl~ y signals bet~een wireles~ telephones and a broad~and 10 distribulion network that carrie~ telcpho~ signals to a telephone network Back~round of the lnvention The prior art leaches the use of existin~ cable îelevision networl; cables to carr~
5 teleph~ny si~nals between a telephone network and remote transceiver sites in defined cells or sectors 'rhe transGeivers are used to establish wireless telephony communication link~ with wirclcss telephones that ale operating withiin ~n ~rea cowred by each remote transceiver. To increase the number of wireless ~t~le~h~ne subscnbers that c~n use the wireless teleph~-ne sys~em it has been suggested to decreasc the size and operational ran~,e of each cell or sector~
20 and to incre~se the num~er of ~ells or sectors required to provide wireless telephone serYic~ to a given uea Havin~ or ~ectors of decreased size penn~ts ~sreater reuse Df the limited number of fiequ~ncy chdnneli ~llocated for wireless selephone service because other ~ells or se~tors l~cated ~t ~ clDser r~n~e can reu~e the s~lme f;equency cl~nr -I for additional calls ~thout ~ignal interference. The advanta~es of reducin~ oell or sector ~ize to increase the call 2S canyin~ capacity of the wireless leleFh~ne network is ofl~et by the requirement for additional remnte transceivers for the additional cells. This offset is n~inimized by 11-ili7il~5 an existin~
broadband distri~ution network to pra~ide the cormnunicationc path ~etween remote transceivers in each of ~he cells or s~ctors and a centr~l tr~scei~vel Th~ b~e transceiver CIE{-2~ 97 14:11 FROM: CA 022i590l l99'7-l2-24 T~ t'~ 32 8~0 PRGE:04 ~326 ~ R~m~el~ Cohlroll~d ~n C~l OJ T~w~i~a U~cd To Ir~ Wu~lc~ Teleph~.ne:~ To A ~d~J ~ch~or~:
station acts as the in~er~ace b~tween the telephone network and the wireless telephone system, ~nd the central transeeiver acts as the wireless telephone system interface with the bro~dband distribl~ion network To carry wireles~ telephony si~nals over ~ broadband distri~ution network, as described above, ~ predetermin~d b4ndwi~th ~n ttle networ~; is typically a~ ca~ed fDr this purpose.
owever, as required7 more bandw~dth m3y be aJlocatcd to c~lry wir~less t~l~rh~ y si~nals.
Tc~ most efficiently use a given bandwidth to c~y ~4~reles~ telephony Sigllal~ bet~een wireless telephones ~ld thc ~ phl~ne network, a ~mbin~tion of ~e~uency and time divis;~n 10 muhiple~in~ is utilized This req~i~es base transc~iver st~tion eq~lipment that acts as the int~ ce with the lelep~ne network and the wireless telephone ~ystem With the base transceiver station equipment is a central trsnsceiver ~RASP), als~ called a Jleadend Interface Clo~verter ~H~C)~ ti-al interfaces ~vith the brordb~ distributiun network ~nd it must fimction with telcphony si~nals in the wide ~equency spectrum of r~di~ freql~ency si~nals on the 15 t~lephone network. ~Ind up lo 1000 ~z over the broetlh~n~ ~istribution network This systom also requires a plurality ol'remote transcei~ers, also called cable micr~ell inl¢grators (CM~s~
or Remote Anterula I~ri~ers (RADs~, in each of the cells or s~ctori that can c~rry m~ny channels of tel~phony sign~ls betw~n the w~rel~s telephone~ and the eentral lranscciYor via the ~r.~h~nd distribution n~twork, ~ithout creatin~s si~snal in~ ren~e with ;he teleph~ny u sign~ls in adjacent cells ~r sectors In addition. ~he remote transceivers (RAD j~ must ~nction with and translate lelephony si~n~l~ in the ~ide i~equency ~pectrums of up to 1000 Mh~ on the broa~ nd dislribution n~twork and between 18SO - l~gO ~Hz for the radio link be~ween ~emote transceiver~ and w~reiess t.,l~hl-l,es 2 5 In a~dition. the relnotely lo~ated transçeiYers ~nd the bros~band distribution network are exposed tO mJmerous a~verse Cf ,1'~ r~ suçh as te~ e~ah~re extremes, whiGh adversely ~ffect the power levels output ifrom the tnnsceivers, ~nd a~ec 105se5 and gains along the br~ad~anll distnibution network. The po~4er levels output ~m the remote transceiv~r~ must DEC-Z~ 97 14:1~ FRO~ CA 02225901 1997-12 24 TO:~13 232 8:1~0 P~(~E:E15 1~43~ - Ren~ely C4n~ C~ol Of T~Dci~ wJ To Inl4r~cnn~ W~b~ I elcph~r~ T4 A ~adb~l~ N~lwark be constantly moni~ored and ~ sted to cnmpensate f~r these adverse conditions ln addition~
~ueh remote transceivers need to con",~ e not only for network variations between each rem~te tr~ns~ei~er and lhe ~ traJ trulsceiver, but al~ for the temporat variati~ns in the v~rious network links between Ihe remole ~nd central tr~nsceivers Summary s~f the In~/enti~n Thus, there is a need in the an for tr~nsceivers or RAD~ for use in such a wireless telephony system to carry telephony sign~ls between a telephone network and w~reless 10 tel~phol~es ~ia a broadb~nd distributiotl net~o~k alon~ which are ren~otely distributed a plurality o~the transcei~ers The gain ofthese remote trhJ~ ers will be adjust~d ~y the central transceiver which is mon;itonn~ the pow~r levcl of signa]s recei~ed firom euch remote transceiver so that sicnals reeeived from the wireless telephones ure at ~ consistent level, that is wi~hin a relatively narrow lccepta~ility raulge, when inpllt to the central lransceiver lS
The abo~/e described need in the wireless teleph~ne system prior art is s~ti6fied by the present inventiun. A ~mal~ transceiver is provided which is u~d in a wirelsss tel~phone system of the t~e briefly described above These remotely located tran~ceivers ue used to cany telephony si~nal~ between wireless telephones and central transceivers via a broadband 2 ~ di~tribution network, such as ~C~ fiber OptlC c~blel or co~xial cable, on which the remote transceivers are hun~ ~nd t~ which they are connected Thus, these remote transceivers are remotcly l.~cat~d and ~linullate tlle n~l for prior r~ an~enna to~Yers ~o carry telephony signals between wi~eless telephones and central transceivers Each remote transceiver has ~ain ~ontrol citcuitry by which the ~ n ~ Ihe remote transceivers can be adjusted by the centr~l tr~nsceiver 2 5 which is monitoring the power level of a gain tone signal received from each relnote u~.3~iver. This is dnne sO that the signal level oft~ ny si~n~ls from the wireless telephones and appeanng at the input of Ihe cent¢al l~.,scL;~er are at a ~onsistent level th~t is ~thin a relatively narrow r4nge a~ceptable to the central transceiYer.
OEC-24 97 14.12 FR~. b~3-885-~1~7 10:ol3 2~ 8~40 P~GE:06 CA 0222590l l997-l2-24 ~3~ - Q~w~l~ C~olled G~r ~1 ~Tn~iva U~ T~ ~n~ Wi~k~ Tcl~ ToA~d~d~o~
Descnption of the Dr~wing The invention will be better understood upon readinl3 the fo]lowin~ Petailed l:)e~cr.~tion in conj~lnetior ~4ith the drawing in which:
S
~ igure 1 is a bl~k diagr~n of a wireless telephony sy~teln integrated ~ith an eY~ lpl~ybrosdbu~ddistnbu~ionnetwork.
Figure 2 is a simplified blo~k dia~ram of a ren~ote tr~nseeiver u~e~ w,ith the wireless 10 lelephony system, Figure 3 is a det~iled block diagranl of the portion ~f a remote tr~nsceiver that transmits telephony si~nals received ~on~ wireless teleph- n~ and sent Yia a bro~dh~nd dlstribution network to a central transceiver~ and the remote transceiver has gain control 15 circuitry that i~ rernotely controlled by the central transceiver; and Figure 4 i~ a block ~ia~lram of a portion of ~ central transceiver that is used to monitor Ihe si~nal g~in of ~ gain tone recei~ed from each of ~ plurality of remote transceivers ~ong with telephony signals, and send control sign~ls to each remote tr~nscei~er to adjust its signal 2 0 g8in Det~iled ~ riptinn In the dra~in~ and the folio~ det~iled description, all ~lements are ~c~i~ned three 2 5 digit reference numbers rhe first digit ~f each reference number indicates in which fi~ure of the drawin~ an element is loeated The second and third digits of each, efe ce number indicate s~ecific elements If the same element appeus in more than one figure of the drawin~.
the second and t~urd digits rema~n the ~ame ~nd only the first digit chanyes to iE~diçate the ~r~ '~ - ~1~7 ~ bl3 2i~ 8~4~ P~I~E:07 DEl~-24 g~l' 14:l2 FRO1'1: CA Oi225901 1997-12-24 D4326 ~ eiy l~ollcd ~;b~n C~rol Of T~iva Ibd To I~ W~rcleb~ pho~ T~ db~nd ~i ~tW4~A
figure of the drawing in which th~ element is located As used herein the terrn "~elephony ~i~n~ls" incl~de~ voice, d4ta, f~x and any oth~r types of si~r~als that are sent over a telepholle net~ork now or in the fi~ re. Throughout the ~i~res and lhe followin~ descripti~nl refe~ence is m~de f~r one exs~le, [o a combined band pass filler ~nd ~snplifier 3~5a. There ~re a S nu~nber of other such c~mbined band p~ss fiJterD and ~mplifiers. They are ~hown and refereTl~d this way for e~se of pre~entation only. In reality they are eacb a discrete, separate filter the out~ut of which is input to a n ~"~rlifi~t ln Fi~ure 1 is sho~n ~ simple block dia~raJn of an ~ mF!A~ broadband distnbution10 network 112 integrated with ~ wireless tcle~honc system whicb includes a plurality of remotely 1nc~ted trans~eivers known aS Remote Antenn~ Drivers ~RADs~ . Ther~ are differ~nt types of broadb~nd distri~ution networks in use that m~y be utilized ~4ith the pre~ent invention Such networks may utili~e coa~i~t c~ble ~nd fib~r optic ~able rn thc embodiment of the invention diselos~d herein a conventional hybrid fiber ~oax~sl (~FC~ cable distribution s~slem 15 is utilized o~the type u~ed for cable ~elevision distri~ution nel~orlcs~ but other types or combin~tions of broadband distribution network~ may also be utilked Electrical power is distributed ~lon~ ~road~and di~tribution network 112 to power line amplifiers (not shown) of the btoadband distribution network This electri~al power source ar alternate power sources, are used to provide power to RA~s 11~ a-i ~o In~e~rated with ~roadband distribution network 112 i~ a wireless telephony system in which the presen~ invelltion is ~Itili~ed. One j-lch wireless telephony sy5tem is taught in U S
Pat~nt application 081~5,175, filed Au~ 1, 1996, and entitled "Appara~us And l~,~ethod For Distnbuting Wir~le~s (~ommumcati~ns Si~nalj To ~omote Cellular Antelulas". The tclcphon~
5 system di~closed herein and shown in Fi~ure 1, in~ s a base l~an~ceiver station (HTS) I 1 S
which is wnnected tC) ~I telephone system I 16 Base transceiver xtation 1 15 i~ also c~nne~t~d to a Remote ~ntenna Signal Proces~or (R~SP) I ~ 7 ~bhich is the interface to a bro~dband distribution network 1 12 Telephony si~nals to be sent between telephone sy~ern 1 16 and Z4 g7 1~: 13 FROI~I: CA 0 2 2 2 5 9 0 1 19 9 7 - 12 - 2 4 Pi~GE: 08 ~431~ - p.crnolcl y Cor~l loA4 ~un C~l ~ Us~d T~ W irt l~ l tlcph~ l o A E~ro~ ctwDr.~
wirel~ss tel~Fhon~s I 1~ ~re carried via t~ro~d~on~1 network 1 12 using RASP I 17 an~ Remote Antenn~ Drivers (RAD) 118.
A~ is l;nown in the prior art, in~ n~s the l~bo~/e ~ited pnor art patent applic~ior~ one 5 or more ~equency bands or ch~ ls ofthe braadhand distrlbutic~n network 112 ~re aeci6ned to c~m telephony corn~ n ~h~iOrlc and control signals between telephone system 116 and ~ireless telephones I 1~ Telephony sign~ls originating ~om telephone system I ]6 are ,.utted ~y RASP 117, in *eq~ency division mu~ d~e furmat, via bro~d~nd network 112 to ~ plur~lity of remote antenna dnvers (~ADs~ i which are connected to broad~and 10 distribution network 1 1~ Te~ephony signal~ ori~in~ti~ ~t wireless tPleph~n~s I 1~ are ~equency mul~iplexed to~t~th~r by RADs 118 ~-i and ~re transmitted alon~ with contrvl and ~in tone signals via ~roadband net~ork 11~ to ItASP 1 17, al1d Iher~e to base trans~ er station 1 I S and telephone syssem 3 In ba~ ans~.~er station 115 there are a plurality oftranscei~er modules (not shown~
as is known in the wirele~ telephony an, e~ch of ~hich opcrates ~t a single channel frequen~y ~t a timc, and which can handle ~ predel~fu~."ed m~Y~ m number of telephone calls ~om wireless telephones In the wireless telephone system described and cl~imed her~in, ~he frequen~y ~h~t the RADs I 18 are as~igned to operate at must c~rrespond to the operating 2 0 fre4uency of the assigned BTS transceiwr mod~le If ~ particul~r R~D 1 18 is re-assigned tO
fiunction with a di~erent transceiver module ~ithin ~ase transceiver station 11~, ~ir~uit se~tings wilhin ~he particular RA~ must ~e ~ ng~d to fi~nclion wil~ the dit~rent transceiver module. Irl the wircless telephDny art, transceiYer modules in Iht b~se transceiver station are also referred to ~s ch~nnel cArd modulcs and radio mc~dul~6.
When wireless telephony traffic in a first ~ector or ceD incre~se~ to the point where adequate ser~ ice i5 not provided to wireless telephone subscribers in the first sector or celL lil~e during rush hour traffic on a hi~hw~y~ in accordance with the tea~kin~ of the present invention 9 ~7 14 13 FRI~ F3~ 7 I~ bl3 232 ~ P~GE: 0~E~-2 . . CA 0222~901 1997-12-24 D~132~ Remu~ely L'onuollcd ~}~u C'~nlrol O~Tr~ iVa Uccd To Inlcr~q~ ~'uele~ lcl~phne~ To A i~ir~dbu~d Ne~
the wireless telephone Syslem may be remotely reconfigured by RASP 117 to reassign one ~r more RADj 1 18 from one or m~re nearby ~ectors or cells, where those ~A~s I I g have overl~ppin~ signAl cov~ra~e wi~h t~e fir~t sector or c~lL ~o handle the ex~ess wireless telephony traffi~ in the first sector cell.
ln Fi~ure I ar~ shown three rows of R~Ps I 18. Typically a number of R~I)s 1 18 are spaced alon~ and connected t~, bro~dband dis~ ution network 112 to pro~id~ overla,ppin~
sign~l transm~sion and reception covera~e for the entire wireless teleph~ne system. Some of the RADs 11~ are physically l~eated ne~r the bounJ~ry between tw4 or more cells or sectors 1 n and, ~epe~ on the frequency of operation th~ are set to, can be used to handle ui~eless telephony traffic in o~e or more of the sectors or ceils Let us ~ssume lhi~t RADs I 1~ ~,h~i in the bottom rov~ are physica]ly lac~ted along bro.l lb~nd distri~ution system I 1~ and ~re configured to handle wireless telepholly tr~ffic in a first ~ctor tha~ includes a highway. I:~unn6 early mornin~ and late afternoon every work day there is nl~h hour traffic that creates pe~k 15 wireless telephone trdffic that c~useY UqR ~c~ptable sen~ce delays in the first sector. Let us also a~s~me that the RAPs 1 1 ~d,e,f in the middle row in Fi~ure I ~re confi~ured ~nd locat~d to handle wuele~s telephone traf~ic in a se~ond. adj~cent ~eetor but they ea~h have an ~rea of signal operation that overlapj the hi~h~ay in the fir~t sector O One or more of RADs l 18 d,e,f may be dynan~cally reassi~ned by R~SP ] 17 to the first sector lo h~ndle the increased t~lephony traffic oniginating ~om the highway ln addition, ~5 necesja~, addition~ ASP 117 ~hannrIc may be a~ igne~1 ~nd additional modules in base tran$~eiver station 1 15 may be assigned to handle the excess wireless teleph~ny traffic firom the first ~e~tor To do this RASP I 1 ? sends control ~i~n~ls to the ~elected remote RADs d,e,f which ~ill cause the frequenGy at which they operate to be changed lo mat~h the frequency of RADS 1 18 g,h i that are nonnally as~ d to handle wirele~s telephone traffic in the first sector ~t the end of the peak traffic per~oJ RASP I 17 may jend control siynaJs to the previously re~llo~ted ones of RADs 1 I 8 d,e,f to C~ jSe lhe frequency at which they operate CIEC-ZY 97 14:14 FROM: CA 0222590l l997-l2-24 bl3 _3~ ~4413 Pf~GE:10 1~43~ . Rcmah~ C~-~llc~ 13D~J) ~ ol (~rl'n~i~a U~ To ~ l Wucles~ ~I'dcph~nc~ T4 A ~r~dbu~ ~e~ rl~
b3ck 10 th~ir original settinys ~ they are reassigned to handle wireless telephony traffic in the second sector ~lo~-ever, the r~-assignrnent may be permanent dependin~ on t~affic patterns encollntered Typically ~here are a nurnher of R~s 1 18 ~-i spaced ~long snd connected to broa~l-~ntl distnbution network 112 to pra~ide overlappin~, si~nal trAnsrnission and reception coverage fior the entire w~reless telephone system Each RA~ 1 18 has anter~n~s 120, 121, 12 used to transmit to and receive jiynals from remote wireless telephones 1 19. Anlenna 120 is used to transmit telephon~! signals to wireless telephones 1 l~, while antennas 12i and 1'2 are used to receive lelephony signals firom ~ireless t~l~,nl~nes 119. ~ultenna 121 is called the pnnnary antenna, and ant~nna 1~ is called the diversily ~nteMa Antennas 121 ~and 1~2 are physically spaced and c~opera~e to minJrn~ze signal fading and ther~by provide continuous si~nal r~ception from wirelL~s telephones 1 19.
In Fi~ure 2 is shown ~ ~eneral block dia~ram of Remote Am~nna l~riv~r (RAD) ~18 The~e is a first circuit 20~ of ~AD 218 that receive~ telephony 5i~nals or~inatine at telephone system 1 16 2nd carr~ed ~ia R~~SP 117, ~ro~dl~and network 212, and tra~s~ts them via antenna 220 of a RAD 1 18 to a remote wireless telephone I 1 g (not shown~. There is ~lso a sec~nd circuit 209 of R~D 218, that is shown in det~il in Figure 3, that receives ~eiephony 2 0 si~nals origin~lin~ at a ~ireless teleph~ne I 19, and t~n5mits them via broadband distribution netwo~L 21~ lO RASP I l 7~ ~nd ~hen~ lo ba~e t~ er ststion ~ nd telephone system~16.
RAl) circults 208 and ~0~ are connected to and controlled by a microprocessor 210.
2 5 Frequency multiplexed with the telephony signals calT.ied beIween ~ASP 1 17 and each of RADs 218 a-i are signals for controllin~ ~ain control circuitry in each of remote RAD~ ~18 a-i in a-~ordance with the teac;hing ofthe present invention The ~ain control circuitry in RAD
c}rcuit 20~ , alle~ by RA~SP 1 1~ to adjust its output signal level so th~l the power level I~EC-i~4 97 14:14 FRQM: CA oi22S9ol lgF'97-l2-24 Tn~ 32 ~1~4~3 Pfll~E:
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of telephony si~nals inpul to R~SP 1 17 is wilhin a relatively narrow ran~e acceptable to RASP
1 17. This is rrpeated for all rernotely loc~ted ~ADs 11~ a-i distnbuIed along and ~o~ulected ~o the ~roadband distributian network 21~.
Microprocessor ~10 sends a conuol aignal via leBd ACi~ to RAD circuit ~09 which causes the output of an ~scill~tor 342 ~aïn tone si~ , w~th known si~nal le~el, t~ be ~-on~bined with any teleph~ny signal~ and transmitled to RASP 117 ~ria bro~band di6tribution network 112.
The gain tone siKnal level is of a low a~rlit~de that does not interfere with Ihe elephony si~snals with ~hich it is mixed, bllt is s0pasated from the telephony si~nals at ~ASP
1 17 RA SP 1 17 lnalv~es the amplitude of the received g~qin tone signal~ which will reflect gains and losses in ~AD 218 and brc~hand dislribution network 212, hS part of a ~etennination whether or nut t~ chan~e attenu~tor 330a, 330b and 336 settin~s in RA~ 21 This operation is repe~ted fur each remotely located RA~ 21~ so that lhe power level of telephony signals input to RASP 117 is ~vithin a relatively narrow range acceptable to EtASP
117.
~fter processinR the ~in tone signal received alon~ with telepllony signals ~orn each 2 0 of the RP~Os ~18 t~ determine Jf the si~ l le~rels are too 3Ow or too high, RASP I 1~ sends 4din t-)ne cc)ntr~l ~ignal back lO e~eh RAD 218 in which the siKnal level has to be ~dju~ted Thl~ control sianal is received by m~croprocess~r 210 on lead~ CTRL ~om RA~ ~ircuit ~08 Micrnproc~ss~r 210 re~ponds to the gain tone control si~nal re~eived ~om R~SP 1 17 ~ end an AC;C a~justment si~nal vi~ leads AGC ~o ~D circuits 208 ~nd 20g In R~I) circuit ~0 2 5 the A~ adjustment signal results in changes being made to attenuators in circ~it 20~, ~s described in ~reater det~l with referenee to Figure 3, to adjust the signal level of rhe telephony signal~ lhar are received by RASP 117. Thi~ ad~ menl a~count~ for losses And y~ins nnt only in RA~ 218, but ~1so in bro~b~nd distribution ne~w~rk 212 ln this manner the power level GEC-Z~ 97 14:15 FROI~l: CA 022i590l l997-l2-24 TO:~13 232 844~3 P~GE:l~
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of ~i~nais received by l~SP 117 from all RADs 218 s-i are within a relatively narro~v range n~rt ~~1~ t~ SP 1 1 7 RAP 218 may also receive an intetroga~ion control signal ~t sny time from RASP 117 u~hich ca~es rr~croprocessor 210 to send information about R~) 21~ back t~ R~SP I 17 This information includes the s~tings of attenuator pads 330a~ 330b and 336, the semperature at which each RA;~ 218 is operatin~, and other information The inf~rmation list~d in the last sentence i5 used by RASP 1 17 in n~aking decision6 re~arding controllin~ the si~snal level of each RA~ 218.
In Figure 3 is shown a detailed block diagram of RAD circuit 30~ within novel, Rern~te Anterma Driver (RA~) 1 181 ? 11~ that carries telephony signals frorn a wireless telephone 1 19, via broadband distribution network 1 12, to RASP 117 and b~se tr~nsceiver st~ti4n 11~ This cireuit is shown as ~AD circuit 20~ in FiE~re 2.
Briefly, pnmary receive antenna 3~1 is connected to a first por.~tion of the ~ uitry in Fi~ur~ 3, and th~t circuitry is identical to a second porti~n of lhe circuit~y that is connected to diversity receiYc ~ntenr~a 3~2. The telephony si~nals received by ~oth antemla~ 321 ~nd 3'~2 from a wireless tel~phone 1 ] 9 (not shown in Fi~ure 3) are initiall~ processed in puallel~ then 2 0 the two si~nals are frequency multiplexed together and are both returned via broA~b~n~
distribution network 1 12 tO r~m~te RASP I 1~. This operAtion is deseribed in the f~llowinR
puaEraphs.
Telephony sign~ls from ~ wireless t~l~p~onc 1 19 (not shown~ are received by pnmary receive anteMa 321 These si~nal~ are ~nput to an isolator 323a which isolates antenna 321 from RA~ circuit 309 The t~l~phnny si~,n~l is then input to directi~nal coupler 324a that has a ~econd si4nal input thereto firom power di~ider 34~ which is the ~forelnentioned low level, gain tone si~nal that is u~d for g~in control purposes in accord~nce with ~he present inventinn ClEC-i~4 ~7 14:15 FRO~1: CA 0222S90l l997-l2-24 TO:61~ 23~ 10 PHGE:13 D~13~ - Rcm~41y C~lle~ Giin C~,lr~l OrTs~L~ei~,a U~d ~o Inm~Yu~ w~ b Tcl~hc~ To A ~o~db;lnd N~twor~
liain Tone Oscillator 342 is controlled al its input 342a by nucroprocessor 210 whieh is responsive to ~ontrol signals ~om ~SP 1 17. The analo~ ~ain tone si~nal O-ltpUt from ~ain tone oscillator ~42 is at a known a~nplitude and is m~xed with the telephony signal wh~ch is a digit~ pread spectmm format that is ~eli known in the art. lt is this gain tone signal thal is 5 de~ected at RASP 117, processed and used to make a decision to change lhe settings of attenuators 330a, 330~ and 3~.
The telephony signdl received ~om rem~e w~ireless telephone 1 19 and the low level ~ain lone sign~l are applied via directional coupler 324a to a com~ined b~nd p~ss filter and 10 amplifier 325a The ~ ni~ls are amplified and extr~ncous ~ign~ls ~re filt~d ~om the received ~eleph~ny si~nal.
The amplifi~d and fil~ered telephony and gain tone si~nzls are then input to mixer 326a which is the first of two heterodyning stage~ u5ed to ~nven the carrier ~equency of the 15 t~leF~hr~ y si~n~l tu tb~ ~ele~t0d cArrier firequency for tr~n~ n over brc~hqnrl distnbution network 1 12 to Rern~te Anlenna Signal Processor (RASP~ I 17, shown in Figure 1 I~,lixer 326a Al~o has inpl~t thereto a signal ~om local o~cillator 32 î. The first heterodyning signal ~om lo~al oscillator 32? is ~nput to power di~der 3~8 which applies the si~nal ~orn local oscill~tor 327 to both mixers 326a ~nd 326b while p-ovidin~ isol~tion between these tw~
2 0 nuxer~.
The opera~ion of m~xer 326a results in n~ tiple frequenci~s being output ~om theniixer as is known in the art. All the~e signals are input to nurow pass ~and SAW filter and ~mplifier 329a which selects only the dcsired ~quency carrier modulated by the eain lone and 25 telephony Sigllal5 created by nuxe~ 3~6a, and amplifies same.
The trequency xhifled ~rier ~ d~'oted by lhe tel~pl~ony signal is then inpul to step ~ttP~ or 330a which is used to adjust the gain level of the signal in onc ~~~f d~ steps as p~rt CIEC-~4 97 1!1:15 FROM: CA 0222590l 997-l2-24 ~~ ~ 32 84~3 Pf~iE:14 D~32~ R~a~d~ odG~ nuolofT~iv~u~d~ wu~b55lelc~ ~sloA~o~ n4l~e1w4rlL
of the imple"~cn-ation of the pre~ent invention. The ~n~unt of ~tte ~ l~ion provided by step attPn~ or 3 30a is controlled by ~ binary wor~ at its control input 3 31 a ~rom microprocessor 210 Microproce~sor ~10 controls the settin~6 of ~tep ~nenu~o-s 330a. 33ûb and 336 respon~ive to the AGC ~ain con~rol signals received from ~SP 117 as previously descnbed.
S This assuJes that the power level of all teleph~ny signals r~ceivéd by RASP 117 from oll RA~s 218 A-i are w~thin the rel~tively narTow ran~e ar,c e~ ~P~ie ta RASP l l 7 The gain tone and leJephony si~nals oulput ~om step attenu~tor 330a are input tomi~er 33~a along with ~ fixed frequency s om local o~ or 333a Mixer 33Za is the 10 secDnd ofthe aforementioned tw~ heterodyning sta~es However, the ~equency of local os(~ At~r 333B iS different from the frequency of loc~l oscillator 333b l'he result is that the ~rrier frequency of the telephon)~ signal output ~om n-ixer 332a is different than the carrier frequeney ~utput from mixer ~32b l 5 The lelephony signals received by prirllaly antcnn~ 321 ~nd divorsi~y ~nt~nna 322, each now at ~ different carrier frequeney, ~nd the ~ain tone si~nal combined therewith, are c~mbined into one composite signal by co~nt r-- 334. The colnbined signals are first ~Itered by band pass filter and ~mplifier 3~ and then input to step ~ttenu~tor 336 to ~ive a fin31 adj-~stment to the ~i~nal level of these combined signals Similar to the op~ration of the ~0 previously des~r~bed step attenuators, this digit~ly controlled atte~uator 33~ is set by microprocessor 2 l 0 r~sponsiYe to a ~ain contr~l signal received from remote RASP 112 as part of the novel ~,ain control operation The freqllency ml~lt~ x~d telephony signals o~tput ~m step atte~ tor 336 are input 25 to si~n~l combiner 3~? which has a second input fron~ control ~i~nal oscillator 338. The ~requency of Gontrul signal oscill~tor 338 is controlled by B bin~ry sigr~l oll control leads 338a fronl n~icroprocessor ~10 tO set the ~equency of the ~scillato~ RASP 1 1~ is the ori~in ~om which a conlrol si~nal is received to set ~he frequency o~control signal oseillator 338 The EC-2~ ~7 14:1~ F~0~ 0~ 5-Z167 TO:~13 232 8~4~ P~E-15 ~6 - R~ C~oll~ Ouin C~l ~T~I~rU~dT~l~C~w~'~h~Tol~h~TdA~b~d~wk frequency chosen is tO fall withln Ihe b~nd of frequ~nries used for the telephony si~nals received via the prirnary and the diversity ante-ulas Pesror~ e lo different control si~nals received ~om RASP 117, microprocesso~ 210S (FiE~ure 2) sends signals on control inputs 338a. T} ese nucr~processor 210 signals cause contr~l si~nal oscillator 3~8 to produce ~n info~naticln ~ignal. The inforrnation sienal indicates ~arious inforn~atlon about ~ 218, but particul~rly inel~.di~e the settin~s of step anenllato~s 330a, 330b and 336, to RASP 117 as part ofthe novel giin control operation. RASP 117 uses ~his information tO l~oep an upd~t~d status regar.li~ each of the RAD61 18 a-i The output ~nm comhiner 337 now has m~l.tiple teiephony and gain tone si6nals fJequency multiplexed to be re~umed via bro~ d network 112 ~o RASP 117. The signals are the telephony si~nali rçceived by ~ennas 321 and 322, the gJin tone si~ln~ sed ~s part of the present invention, and ~he system information ~i~nal output frorn control si~nal oscill?tor 15 33B This 1;equency mllkiple~ed signal output ~om comt,.j~r 337 is inpLlt to band pass filter and amplifier 33~ ta amp}if~ the signal and to remove any exlr~ne~us si~nals befc~re the si~nal is ~ pled to bro~d~and distributi~n network 112 and sent to RASP I 17 for proee~cin~ In addiIion~ per tt~e teachin~ of the present invention, the signal power level of the telephony 5i~11is such that when i~ is re,~eived at ~SP 117 il is within the relatiYely narrow ranBe O acceytable to RASP 1 17 Iransfor~ner ~nd coupler 340 is used to ~ouple the frequency multiplexed si~nalsdescri~ed in the l~s~ para~raph to broadband distriblnion network 112 The tlansforrner i~ an impedrnce rnatchin~ r~sfomler ha~ring 50 otun pnmary and 75 ohm secondary windin~s 5 When broa~b~nd distrib~tion network 1 1 ~ uses c~acial cable, the secondary winding of transformer 340 is wire~l in ~ries w~th the center conductor ofthe v~deo distr~buti~n coa~ial cable As previously descnbed, RAI:~ ~18 han~ s from the couual cabling of the broadband [~EC-24 97 l4:lo FRCIM: CA 0222 5 90 1 1997-12-24 Tl~:bl-3 ,32 8~40 P~GE:lb P43~6 - R~m~ ConUoll~ /:3~ C~ntrol C~ cr U~d To l~on~ Wir~lc~ r.l.ph~ 1 O A ~ nd Nctwa~k distrib~tion net~40rk 112 to ~ch it is COMe~ted. In other appiicd~ions~ such ~s with fiber opti¢ cable, other well known frequency conversion and si~nal e,ollplinQ techniques are used.
In Fi~ure 4 is shown a block cliagram of the circuitry in RASP 1 17 th~t is used ~o 5 monitor the ~ain tone m~xed w~th teleph~ny and conlrol signAI$ received by R~SP 117 from all RA~ I la a~ bro~b~nd distnbuti~n network 112 There are three inpuIs shown to RF
swit&h 410, desl~ ~ed A, E~ and C Each of these inputs is connecte~l to receive si~nsls from RA~s I 18 oll one se~tor of broadband distribulion network I 12 All RADs I l B on one seclor carr~r telephony si~~nals ar ~I ffrsl camer fiequency Thus, input A will receive tolephony si~nals 10 that have ~ first carrier firequ~ncy, input E~ will r~cei~e teleph~ny si~nals that ha~e a secon~
carrier ~equency, and input C will ~ceive telephony si~nal~ that h~e a third carrier fre4uency ThLIs, with reference to Figure I as ~n example, RA~s 1 18 a-c may all be on one sector and their car~ier signal i~ connecte~ to input A of the circuit in Figure 4, R~Ds 1 18 d-f may all be on ~ second seetor Bnd their ~arr~er signal is connected to input E~ of the circuit in Figure 4, and 5 RADs I 1~ i may aîl be on a lhird seGtor and their carrier signal ls connecteJ t~ input ~ of lhe circ~it in Figure 4 In addition. all the RADs 118 in each sector can simultaneously huidle multiple calls and additional sec~or~ are defined to handle ~diti~nal traffic. If additional wireless telephony traffic must be handl~d, and m~re than three sectors are required, an additional R~SP 1 17 must be plovid~d, and some R~s 1 18 mu&t be re-allocated ~o fùnction o with the addition~ SP I 17 To p~ovide ~i~nals to the ~, B and C inputs, RASP CilCUit 208 has receiver circ-Jit~y c~lMecte~ to each of the three inputs that re~eives telephony and control si~nals transmmed o~ver br~a~b~nd distr~buti~n netw~rk 112 fiom RADs 11~. The re~eiver circuits ~re not 2 5 shown, buI each c~mprises ~n input filter followed by a Si~ llhl divider that applies ~ portion of t~e received siundl lo th~ A, B and C inputs uf the R~SP 117 circuit sh~wn in Figure 4 [~EC-24 ~7 1~:17 FF~0~1: CA 0222590l-l997-l2-24 TCI:~13 ~2 8'~413 P~IGE:17 P43~6 - R~no~ C uluollcd Ci~in CMItral 1~ Trsn~ci vn Li~led Tt~ Imcr~ll,ccl Wuele~ Telq~h~ A E~ro~db~ ~el~t~
Switeh 410 is an RF s~t~h that i5 periodically operated by microproces60r 418 toconnect indi~idusl ones of inputs A, ~ and C to the remainder of the circuitry in Figure 4.
Thus, the poltion ~f circuitry p~st ~witch 410 has input theretol on an indiv~dual basis, the rnulliplexed telephuny si~nals ~om all }~Ds 118 within a ~ector to which it is connected at each mornent in time The telephony si~nal froln each RAD 1 I R has ~ spread spectn rn~
digicized t~310phony 6~nal and the an~ ain tane 6i~na]. The received c~mposite signal frorn all RADs 1 18 within a sector is first amplified by P~nrlifier 411 an~i then input to rn~xer 41'~
alon~ with the o~tput firom IDC~I ~scill~tnr 413. The stuldard heterodyning process of mixer 41~ o produces a number of spurio~ls si~nals. The output of mixe~ ~t 12 ;6 input tD IOW pass ? ~ filter 414 ct~ red around the gain tona which filter6 out most ofthe jpread spectmm signal and the spunou~ si~nals ~o~ ~h~ mixin~ process. This increases the rel~tivo level of the ~a~n tone received from each RAD 1 18 with resp~ct to the ren~oinin~ ener~ of the telephony signal. The resultant ii~nal i5 then ~mrlified at amplifier 415 and input to analog to di~ital eonverter 4~ ~ to chang~ the remain~ng sien~l to a digital signal which is input to digital ~i~nal process<~r 417 for filreher p~oce~ing. The fi~rther p. OC~ 3 thal is performed by Jigital si~nal p~ocessor 417 in dl~ital fonn are the same step~ that have jusl been described for ~he analog ci.euits in Figl~re 4 The digital si~nal that i~ inpl~t to digit~l signal processor 417 is ~igitally heterodyned and low pasj fillered to get ~id of moro, but not all of the r~ in~ telephony 5i~nal. The re~ult is that the ~in lone signal n~ has a 30 dB ~un with rcspect to the O t~lephony si~nal, as compared to the ini~ial p~wer ratios ~enerated by the RADs 118 The ~in tone signal ~om the R~Ds 118 in a soctor is processed ~y microprocessor ~18 and its signal lev~] is compared a~a~nst a st~ndr ~ ~ignal level. ~f the amplitude of the ~~ain tone signal is toQ 10-4~ mi~:roprocessl~r 418 causes ~ ~ain control si~nal to be sent b~ck over 2 5 distr~bution n~tworl~ 1 12 ta the panicular RAD 118 Ihat has the too lo~ gain tor~e This control si~n~l has an address pre-fixed thereto which causes nnly the particular R~ 118 to receive The gain tone conttol signal. Microprocessor ql~ (Figure ~) in the partiGular RAD ] 1 responds to the gain tone con~rol signal and causes a signa1 to ~e output on lead ~GC to [~EC-2497 14:17 FROI'l: CA o222~905 ~9197 12 24 TO:61;~ 232 ~3'14E~ PfiGE: 18 P432~ Ron~tely Coltu~liod O~ Tr~civa ~IR~ To Im4r~ne~:t w~ Telepw~eY To A 13r~n~ N~two~
circuit 20~ (Figure 3) The AGC si~nal is applied to the digital control inputs of step attenuators 330a. 3~b and 336 and causes the attetl~3tion they insert in~o the circuit to be decreased The effect is to i~-cr~asc the power level of the telephony signals ~nd ~ain tone frorn ~ain tone Oscillalor 34~ that i~ combined with the tel~pho~y si~nal and receiYe¢l by th~
CuCult in Fi~ure 4 lf the amplitude of Ihe gain tone is too high microprocessor 418 causes a gain control ~i~n~l to be sent ~ack over distribution net~;ork 11~ to the partic~ r RA~ that ha~ the too high ~ain tone. This gain control si~nal has an ~ddress pre~fixed theret~ which c~uses only the O particular RAD I 18 to receive the 8ain control sign~l. Micr~proc~ssor ~10 (Figure ~) in the particular R~l) 1 18 responds to ~he gain control 6i~nal and causes a si~ndl ln be output on lead AGC to cireuit 20~ (Figure 3) The AGC signal is spplied IO the digital c~ntr~l inputs of step attenuators 3~0~ 0~ and 336 and c~uses the ~ttenuation they insert into the circult to ~e incre~sed The effect is to decrease the power level of the telephony si~nal and ~ain tnn~
1~ transrnitt~d over bro~dband distribution network 112 to R~SP I 17 including the circuit shou~
m Flgure 4 If ~he ~,ain tone si~nal level received and analyzed by the RASP 117 circuil in Fi~ure ~
is eorrect, no ~ain control ~ignals are sent to the pa~ticular RAD 118 to modify tbe setting3 of 2 0 the step anen~ators ~30a, 33~b and 336. As previously descnibed, RAD 1 18 r~ports the ~ettings of its attenuators alld other cir~uits to RASP 11~ using c~ntrol signal oscillator 338.
While what has been dcsc, il~ed hereinabove i8 the preferred embodiment of the ~n control oper~tion oYer a broadband distribl~tion network, it can bc under5tood that numerous 2 5 ch~~,eg m~y ~e ~nade lo the gain control ~ircuilry in RA~ 21~ and RASP I 17 by tho~ skilled in Ihe art with~ut departing from the scope of the invention
Claims (18)
1. In a wireless telephone system that utilizes a plurality of remote transceivers to carry telephony signals between wireless telephones and a central transceiver over a broadband distribution network, and each of said remote transceivers receives control signals from said central transceiver, apparatus in said central transceiver for monitoring and adjusting the gain level of signals sent from each of the plurality of remote transceivers to the central transceiver so that the signal level from each of said remote transceivers is substantially the same at the input of said central transceiver, said apparatus comprising;
means in said central transceiver for receiving a gain tone that is sent along with said telephony signals received from ones of said remote transceivers; and means in said central transceiver responsive to said received gain tone from said ones of said remote transceivers for sending a gain control signal to corresponding ones of said remote transceivers which causes the adjustment of the gain level of signals output from said corresponding ones of said remote transceivers.
means in said central transceiver for receiving a gain tone that is sent along with said telephony signals received from ones of said remote transceivers; and means in said central transceiver responsive to said received gain tone from said ones of said remote transceivers for sending a gain control signal to corresponding ones of said remote transceivers which causes the adjustment of the gain level of signals output from said corresponding ones of said remote transceivers.
2. The invention in accordance with claim 1 wherein said means in said central transceiver for receiving said gain tone from ones of said remote transceivers comprises:
means for separating said gain tone from said telephony signals received from said ones of said remote transceivers, and means for analyzing said gain tone received from said remote transceivers to determine if the gain tone signal level is above or below a predetermined level.
means for separating said gain tone from said telephony signals received from said ones of said remote transceivers, and means for analyzing said gain tone received from said remote transceivers to determine if the gain tone signal level is above or below a predetermined level.
3. The invention in accordance with claim 2 wherein said means for separating said gain tone from said telephony signals received from said remote transceivers comprises filter means.
4. A method for monitoring and adjusting the gain level of each of a plurality of remote transceivers that carry signals between wireless telephones and a central transceiver over a broadband distribution network, so that the gain level of signals output from each of said remote transceivers and present at the input of said central transceiver is substantially the same, said method comprising the steps of:
receiving in said central transceiver a gain tone that is sent along with telephone signals transmitted from ones of said remote transceivers; and returning a control signal from said central transceiver to corresponding ones of each of said remote transceivers which causes the adjustment of the gain level of signals output from said corresponding ones of said remote transceivers.
receiving in said central transceiver a gain tone that is sent along with telephone signals transmitted from ones of said remote transceivers; and returning a control signal from said central transceiver to corresponding ones of each of said remote transceivers which causes the adjustment of the gain level of signals output from said corresponding ones of said remote transceivers.
5. The method in accordance with claim 4 further comprising the steps of:
analyzing the gain tone received at said central transceiver from each of said remote transceivers to determine if its signal level is above or below a predetermined signal level; and determining the value of said control signal to be returned to said corresponding ones of said remote transceivers which causes the adjustment of the gain level of signals output from said corresponding ones of said remote transceivers.
analyzing the gain tone received at said central transceiver from each of said remote transceivers to determine if its signal level is above or below a predetermined signal level; and determining the value of said control signal to be returned to said corresponding ones of said remote transceivers which causes the adjustment of the gain level of signals output from said corresponding ones of said remote transceivers.
6. The method in accordance with claim 5 further comprising the step of separating said telephony signal from said gain tone in said central transceiver before analyzing said gain tone to determine if its signal level is above or below said predetermined signal level.
7. In a wireless telephone system that utilizes a plurality of remote transceivers to carry telephony signals between wireless telephones and a central transceiver via a broadband distribution network, and each of said remote transceivers receives control signals from said central transceiver, apparatus in said remote transceivers responsive to control signals received from said central transceiver for adjusting the gain level of signals output from each of said plurality of remote transceivers and sent to the central transceiver so that the gain level of signals output from each of said remote transceivers and present at the input of said central transceiver is substantially the same, said apparatus comprising:
means for transmitting a gain tone along with said telephony signals from each of said remote transceivers to said central transceiver over said broadband distribution network;
means in each of said remote transceivers for receiving a control signal directed to it from said central transceiver; and means for adjusting the gain level of signals output from each of said remote transceivers responsive to said control signal directed to each of said remote transceivers.
means for transmitting a gain tone along with said telephony signals from each of said remote transceivers to said central transceiver over said broadband distribution network;
means in each of said remote transceivers for receiving a control signal directed to it from said central transceiver; and means for adjusting the gain level of signals output from each of said remote transceivers responsive to said control signal directed to each of said remote transceivers.
8. The invention in accordance with claim 7 wherein said means for adjusting the gain level of signals comprises:
gain control means through which said telephony signals and gain tone signal pass on their way from said remote transceiver to said central transceiver; and means responsive to said control signal for changing said gain control means so that the gain level of signals output from each of said remote transceivers and present at the input of said central transceiver is substantially the same.
gain control means through which said telephony signals and gain tone signal pass on their way from said remote transceiver to said central transceiver; and means responsive to said control signal for changing said gain control means so that the gain level of signals output from each of said remote transceivers and present at the input of said central transceiver is substantially the same.
9. The invention in accordance with claim 8 wherein said gain control means comprises amplifier and attenuator means.
10. A method for monitoring and adjusting the gain level of each of a plurality of remote transceivers that carry signals between wireless telephones and a central transceiver over a broadband distribution network, so that the gain level of signals output from each of said remote transceivers and present at the input of said central transceiver is substantially the same, said method comprising the steps of:
transmitting a gain tone along with said signals output from each of said remotetransceivers to said central transceiver via said broadband distribution network;
receiving a control signal at ones of said remote transceivers and directed to it from said central transceiver, and changing the gain level of signals output from each of said remote transceivers responsive to said control signal directed to its so that the signal level of signals received at the input of said central transceiver from each of said remote transceivers is substantially the same
transmitting a gain tone along with said signals output from each of said remotetransceivers to said central transceiver via said broadband distribution network;
receiving a control signal at ones of said remote transceivers and directed to it from said central transceiver, and changing the gain level of signals output from each of said remote transceivers responsive to said control signal directed to its so that the signal level of signals received at the input of said central transceiver from each of said remote transceivers is substantially the same
11. In a wireless telephone system that utilizes a plurality of remote transceivers to carry telephony signals between wireless telephones and a central transceiver over a broadband distribution network, and each of said remote transceivers receives control signals from said central transceiver, apparatus for monitoring and adjusting the gain level of signals output from each of the plurality of remote transceivers to the central transceiver so that the signal level output from each of said remote transceivers is substantially the same at the input of said central transceiver, said apparatus comprising;
means in each of said remote transceivers for transmitting a gain tone along with said telephony signals output from each of said remote transceivers for transmission to said central transceiver via said broad band distribution network, means in said central transceiver for receiving said gain tone from each one of said remote transceivers, and means in said central transceiver responsive to said received gain tone from each of said remote transceivers for sending a control signal to ones of said remote transceivers the output signal gain level of which is above or below a predetermined level.
means in each of said remote transceivers for receiving said control signal directed to it from said central transceiver, and means in each of said remote transceivers for adjusting the gain level of signals output therefrom responsive to said control signal.
means in each of said remote transceivers for transmitting a gain tone along with said telephony signals output from each of said remote transceivers for transmission to said central transceiver via said broad band distribution network, means in said central transceiver for receiving said gain tone from each one of said remote transceivers, and means in said central transceiver responsive to said received gain tone from each of said remote transceivers for sending a control signal to ones of said remote transceivers the output signal gain level of which is above or below a predetermined level.
means in each of said remote transceivers for receiving said control signal directed to it from said central transceiver, and means in each of said remote transceivers for adjusting the gain level of signals output therefrom responsive to said control signal.
12. The invention in accordance with claim 11 wherein said means for receiving said gain tone from each of said remote transceivers comprises:
means for separating said gain tone from said telephony signals received from each of said remote transceivers; and means for analyzing said gain tone received from each of said remote transceivers to determine if the gain tone signal level is above or below a predetermined level.
means for separating said gain tone from said telephony signals received from each of said remote transceivers; and means for analyzing said gain tone received from each of said remote transceivers to determine if the gain tone signal level is above or below a predetermined level.
13. The invention in accordance with claim 12 wherein said means for adjusting the gain level of signals comprises.
gain control means through which said telephony signals and said gain tone signal pass on their way to said central transceiver; and means responsive to said control signal for changing the operation of said gain control means so that the gain level of signals output from each of said remote transceivers and present at the input of said central transceiver is substantially the same.
gain control means through which said telephony signals and said gain tone signal pass on their way to said central transceiver; and means responsive to said control signal for changing the operation of said gain control means so that the gain level of signals output from each of said remote transceivers and present at the input of said central transceiver is substantially the same.
14. The invention in accordance with claim 13 wherein said means for separating said gain tone from said telephony signals received from said remote transceivers comprises filter means.
15. The invention in accordance with claim 14 wherein said gain control means comprises amplifier and attenuator means.
16. A method for monitoring and adjusting the gain level of each of a plurality of remote transceivers that carry telephony and other signals between wireless telephones and a central transceiver via a broadband distribution network, so that the gain level of signals output from each of said remote transceivers and present at the input of said central transceiver is substantially the same, said method comprising the steps of:
transmitting a gain tone along with said telephony signals output from each of said remote transceiver for transmission to said central transceiver via said broadband distribution network;
receiving a gain tone along with telephony signals in said central transceiver from each of said remote transceivers, sending a control signal from said central transceiver to corresponding ones of each of said remote transceivers which causes the adjustment of the gain level of signals output therefrom;
receiving a control signal at said corresponding ones of said remote transceivers and sent to it from said central transceiver, and changing the gain level of signals output from each of said remote transceivers responsive to said control signal directed to it so that the gain level of signals received at said central transceiver from each of said remote transceivers is substantially the same.
transmitting a gain tone along with said telephony signals output from each of said remote transceiver for transmission to said central transceiver via said broadband distribution network;
receiving a gain tone along with telephony signals in said central transceiver from each of said remote transceivers, sending a control signal from said central transceiver to corresponding ones of each of said remote transceivers which causes the adjustment of the gain level of signals output therefrom;
receiving a control signal at said corresponding ones of said remote transceivers and sent to it from said central transceiver, and changing the gain level of signals output from each of said remote transceivers responsive to said control signal directed to it so that the gain level of signals received at said central transceiver from each of said remote transceivers is substantially the same.
17. The method in accordance with claim 16 further comprising the steps of:
analyzing said gain tone received at said central transceiver from each of said remote transceivers to determine if its signal level is above or below a predetermined signal level, and determining the value of said control signal to be returned to said corresponding ones of said remote transceivers which causes the adjustment of the gain level of signals output from said corresponding ones of said remote transceivers.
analyzing said gain tone received at said central transceiver from each of said remote transceivers to determine if its signal level is above or below a predetermined signal level, and determining the value of said control signal to be returned to said corresponding ones of said remote transceivers which causes the adjustment of the gain level of signals output from said corresponding ones of said remote transceivers.
18. The method in accordance with claim 17 further comprising the step of separating said telephony signal from said gain tone in said central transceiver before analyzing said gain tone to determine if its signal level is above or below said predetermined signal level.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2225901 CA2225901A1 (en) | 1997-12-24 | 1997-12-24 | Remotely controlled gain control of transceiver used to inter-connect wireless telephones to a broadband network |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2225901 CA2225901A1 (en) | 1997-12-24 | 1997-12-24 | Remotely controlled gain control of transceiver used to inter-connect wireless telephones to a broadband network |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2225901A1 true CA2225901A1 (en) | 1999-06-24 |
Family
ID=4161952
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2225901 Abandoned CA2225901A1 (en) | 1997-12-24 | 1997-12-24 | Remotely controlled gain control of transceiver used to inter-connect wireless telephones to a broadband network |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2225901A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2000072475A1 (en) * | 1999-05-20 | 2000-11-30 | Transcept, Inc. | Improved reverse path autogain control |
-
1997
- 1997-12-24 CA CA 2225901 patent/CA2225901A1/en not_active Abandoned
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2000072475A1 (en) * | 1999-05-20 | 2000-11-30 | Transcept, Inc. | Improved reverse path autogain control |
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