Abstract:
A method for automating a card game includes wirelessly interrogating each of a plurality of playing cards using radio frequency transmissions. For at least some of the playing cards, determining a rank of the playing card is based on the wireless interrogation using a mapping stored on a computer-readable medium that uniquely identifies playing cards based on a random distribution of conductive material carried by each of the playing cards.

Description:
FIELD OF THE INVENTION  
       [0001]    The present description generally relates to gaming, and in particular to games played with playing cards. 
       DESCRIPTION OF THE RELATED ART  
       [0002]    Casinos and other forms of gaming are a multi-billion dollar worldwide industry. Typically, a player exchanges currency or a form of credit for a casino&#39;s chips. The player places the chips as wagers at various games, such as blackjack, baccarat, poker, and other well-known card games. A game operator, such as a dealer, distributes or deals the playing cards, pays out winning wagers with additional chips based on the set of odds for the particular game, and/or collects losing wagers. The odds of each game slightly favor the casino, so on average the casino wins and is profitable. 
         [0003]    Thousands of card hands may be dealt per hour. Like many businesses, casinos wish to monitor these transactions as closely as possible. Monitoring may help the casino identify cheating by players and/or dealers. Monitoring may also allow the automation of various functions, such as accounting, to improve business efficiency, servicing of the tables including the delivery of extra chips when needed, and/or may providing incentives (i.e., “comps”) to players based on their activity at the gaming table. Many casinos employ individuals commonly referred to as “pit bosses” to visually monitor the gaming activity including the dealing of cards, placing of wagers, payout of winning wagers and collection of losing wagers. A number of automated devices have been proposed for assisting casinos in monitoring the gaming activity. For example, card readers which optically or magnetically scan either standard or special markings on the playing cards to identify the playing cards as they are dealt. Optical scanners have also been proposed for reading markings carried by wagering chips, such as barcodes. Further, radio frequency identification (“RFID”) transceivers have been proposed for reading RFID tags incorporated in wagering chips. 
         [0004]    The use of optical markings has a number of distinct drawbacks. For example, these markings degrade during use for example due to excessive handling and/or spills or stains, and thus become difficult or impossible to read. Optical markings are also difficult to read in the uncontrolled visual environment common in casinos. For example, optical systems rely on line-of-sight, which may be blocked in the uncontrolled visual environment of a gaming table, for example, by a drink or other object placed on the gaming table. Further, players and other casino customers wear a large variety of colors in their clothing, which clutters the visual background, making the optical marking difficult or impossible to read. 
         [0005]    Magnetic marking also has a number of distinct drawbacks. For example, these markings also degrade during use, for example due to excessive handling, and thus become difficult or impossible to read. Magnetic markings must be placed in very close proximity to the reader, which typically requires the swiping of the magnetic marking through a slot in the reader. This would unduly interfere with the playing of traditional card games. 
         [0006]    RFID technology has other distinct drawbacks. RFID technology relies on a semiconductor chip coupled to an antenna. The cost of these RFID chips is rather high, currently on the order of $1.50-$2.50 per chip. Thus each set of 52 playing cards would cost between $78 and-$130, prohibitively expensive for practical use given the extremely large number of playing card sets each casino uses. While these RFID chips tend to be very thin, they are still rather large when compared with the thickness of a playing card. Thus it is difficult to incorporate an RFID chip in a playing card. For example, an RFID chip laminated in a playing card may be detectable as a lump or bump by players, causing the players to reject the playing cards and take their business to other casinos. The RFID chip may throw off the balance of the playing card, again causing players to chose other casinos. The increase in thickness in the playing card may interfere with existing casino systems, such as automatic shuffle devices. 
         [0007]    It is desirable to have a system and method that allows a casino to efficiently automate a card game by identifying and/or monitoring playing cards. It is further desirable to have a common system and method that allows casinos to efficiently identify and monitor both playing cards and wagers. 
       BRIEF SUMMARY OF THE INVENTION  
       [0008]    In accordance with principles of the present invention, a method for automating a card game includes wirelessly interrogating each of a plurality of playing cards using radio frequency transmissions. For at least some of the playing cards, determining a rank of the playing card is based on the wireless interrogation using a mapping stored on a computer-readable medium that uniquely identifies playing cards based on a random distribution of conductive material carried by each of the playing cards. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
         [0009]    In the drawings, identical reference numbers identify similar elements or acts. The sizes and relative positions of elements in the drawings are not necessarily drawn to scale. For example, the shapes of various elements and angles are not drawn to scale, and some of these elements and angles are arbitrarily enlarged and positioned to improve drawing legibility. Further, the particular shapes of the elements as drawn, are not intended to convey any information regarding the actual shape of the particular elements, and have been solely selected for ease of recognition in the drawings. 
           [0010]      FIG. 1  is an isometric exploded view of a playing card according to a first embodiment, where conductive material is deposited on an inner surface of a face substrate and covered with a back substrate, in accordance with principles of the present invention; 
           [0011]      FIG. 2  is an isometric exploded view of a playing card according to a second embodiment, where conductive material is deposited on an inner surface of the back substrate and covered by the face substrate, in accordance with principles of the present invention; 
           [0012]      FIG. 3  is an isometric exploded view of a playing card according to a third embodiment, where conductive material is deposited on two surfaces of an intermediary base substrate and covered by the face substrate and back substrate, in accordance with principles of the present invention; 
           [0013]      FIG. 4  is an isometric exploded view of a playing card according to a fourth embodiment, where conductive material is deposited on an inner surface of both the face substrate and the back substrate, and an insulating or dielectric intermediate base substrate is positioned there between, in accordance with principles of the present invention; 
           [0014]      FIG. 5  is an isometric view of conductive material deposited on a substrate electrically coupled to an antenna, in accordance with principles of the present invention; 
           [0015]      FIG. 6  is an isometric view of a playing card according to another embodiment, where conductive material is distributed in the substrate of the playing card, in accordance with principles of the present invention; 
           [0016]      FIG. 7  is an isometric view of a playing card according to a further embodiment, where conductive material is distributed in ink used to form indicia on the face or back of the playing card, in accordance with principles of the present invention; 
           [0017]      FIG. 8  shows a gaming environment including a gaming table, card shoe, chip tray and discard shoe and automated monitoring system, allowing monitoring of a card game dealt by a dealer to players, and collection and payment wagers, in accordance with principles of the present invention; 
           [0018]      FIG. 9  is an isometric broken view of a card shoe, in accordance with principles of the present invention, holding a plurality of playing cards; 
           [0019]      FIG. 10  is a partial cross-sectional view of a portion of the playing card shoe of  FIG. 9 , in accordance with principles of the present invention; 
           [0020]      FIG. 11  is a plan view of a number of playing cards according to a further embodiment where a position of a conductive material on the playing card corresponds to an identity of the playing card, in accordance with principles of the present invention; 
           [0021]      FIG. 12  is an isometric view of one of the playing cards of  FIG. 11 , in accordance with principles of the present invention, positioned relative to transmitting and receiving antennas and an radio frequency barrier; 
           [0022]      FIG. 13  is a flow diagram of a method of wirelessly identifying playing cards, in accordance with principles of the present invention; 
           [0023]      FIG. 14  is a flow diagram of a method of wirelessly identifying wagers, in accordance with principles of the present invention; 
           [0024]      FIG. 15  is a flow diagram of a method of wirelessly monitoring a playing card game, in accordance with principles of the present invention; and 
           [0025]      FIG. 16  is a flow diagram of an method of determining outcomes of playing card hands in an exemplary blackjack game, in accordance with principles of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0026]    In the following description, certain specific details are set forth in order to provide a thorough understanding of the various embodiments of the invention. However, one skilled in the art understands that the invention may be practiced without these details. In other instances, well-known structures associated with transmitters, receivers, transceivers, antennas, and computing systems, have not been shown or described in detail to avoid unnecessarily obscuring descriptions of the embodiments of the invention. 
         [0027]    Unless the context requires otherwise, throughout the specification and claims which follow, the word “comprise” and variations thereof, such as, “comprises” and “comprising” are to be construed in an open, inclusive sense, that is as “including, but not limited to.” 
         [0028]    The headings provided herein are for convenience only and do not interpret the scope or meaning of the claimed invention. 
         [0029]      FIG. 1  shows a playing card  10  formed from a face substrate  12  and a back substrate  14 . The face substrate  12  includes an outer surface  16  and an opposed inner surface  18 . The outer surface carries various indicia such as a rank marking  20  (e.g., two-ten, jack, queen, king, ace), suit markings  22  (e.g., heart, diamond, club, spade), pips (not shown), and/or illustrations  24 . The inner surface  18  of the face substrate  12  carries conductive material  26 . The back substrate  14  includes an inner surface  28  and an outer surface  30 . The back substrate  14  overlies the conductive material  26  to provide electrical insulation and/or physical protection to the conductive material  26 . The back substrate  14  may be joined to the face substrate  12  through any suitable means, for example, lamination. Where the back substrate  14  forms an outer layer of the playing card  10 , the outer surface  30  typically carries a decorative pattern that is identical from playing card to playing card. 
         [0030]    The number, placement and/or size of the conductive material may be selected based on the rank and/or suit of the playing card  1   0 , to uniquely encode identifying information for the particular rank and/or suit. Additionally, or alternatively, these same parameters can be selected to encode identifying information such as a serial number (numeric, alpha, alpha-numeric or otherwise), to unique identify the playing card  10  with respect to any other playing card used in the casino (e.g., unique with respect to hundreds or thousands of decks of playing cards). 
         [0031]      FIG. 2  shows an alternative embodiment of the playing card  10 . This alternative embodiment, and those alternative embodiments and other alternatives described herein, are substantially similar to previously described embodiments, and common acts and structures are identified by the same reference numbers. Only significant differences in the operation and structure are described below. 
         [0032]    In contrast to the embodiment of  FIG. 1 , in the embodiment of  FIG. 2  the back substrate  14  carries the conductive material  26 . The face substrate  12  overlies the conductive material  26  to provide electrical insulation and/or physical environmental protection. 
         [0033]      FIG. 3  shows a playing card  10  formed of the face substrate  12 , back substrate  14 , and intermediate base substrate  32 . The base substrate  32  includes first and second opposed surfaces  34 ,  36  each of which bear conductive material  26 . The base substrate  32  may consist of an electrically insulative or dielectric material. The conductive material  26   a  on the first face  34  may be in registration with the conductive material  26   b  on the second face  36  to produce a capacitive effect. Identifying information may be encoded into the playing card  10  by varying the number, placement, and/or size of the capacitors formed by the conductive material  26   a,    26   b.    
         [0034]      FIG. 4  shows a playing card  10  comprising the face substrate  12 , back substrate  14 , and intermediary base substrate  32 . In the embodiment of  FIG. 4 , the inner surface  18  of the face substrate  12  bears the conductive material  26   a,  while the inner surface  28  of the back substrate  14  bears the conductive material  26   b.  As in the embodiment of  FIG. 3 , the intermediary substrate  32  may be formed of an electrically insulative material or dielectric material. Further, the conductive material  26   a  may be in registration with the conductive material  26   b  to produce a capacitive effect to encode identifying information. 
         [0035]      FIG. 5  shows a substrate  40  having a first surface  42  carrying conductive material  26   a  and an antenna  44 . The antenna  44  may take the form of a conductive trace deposited or otherwise applied to the surface  42  and electrically coupled to the conductive material  26   a  to form a resonance circuit resonant at a particular resonance frequency. Optionally, a second surface  46  may carry conductive material  26   b,  positioned with respect to the conductive material  26   a  and spaced there from to produce a capacitive effect, to form a resonance circuit resonant at particular resonance frequency. 
         [0036]      FIG. 6  shows a playing card  10  having conductive material  26  distributed throughout the face substrate  12 . The playing card  10  may or may not include a back substrate  14  and/or intermediate base substrate. The distribution of conductive material  26  may be unique to the rank and/or suit of the playing card  10  for uniquely identifying the playing card  10  from other playing cards in the set. Additionally, or alternatively, the distribution of conductive material  26  may uniquely identifying the playing card  10  from all other playing cards used on the casino (e.g., unique with respect to hundreds or thousands of decks of playing cards). The conductive material  26  may be distributed in a controlled manner. Alternatively, the approach may take advantage of deliberate or un-deliberate statistical deviations in the manufacturing process to produce a random distribution of the conductive material  26 . The random distribution of conductive material  26  can later be matched or mapped to a rank and/or suit of the playing card  10  to uniquely identify the rank and/or suit of the playing card in a set of playing cards. Additionally or alternatively, the random distribution of conductive material  26  can later be matched or mapped to uniquely identify the playing card  10  from all other playing cards used in the casino (e.g., unique with respect to hundreds or thousands of decks of playing cards). Data representing the mapping may be supplied in computer-readable form, along with the playing cards. 
         [0037]      FIG. 7  shows a playing card  10  in which the conductive material  26  is distributed in the printed indicia such as the rank  20 , suit  22  or illustration  24 . The conductive material  26  may be mixed into an ink which is then applied to the face  16  of the face substrate  12 . Alternatively, the conductive material  26  may be distributed in ink that is then applied to a back surface of the substrate  12 , for example in back designs common on typical playing cards. Alternatively, the conductive material  26  may be deposited into the ink after the ink is applied to the playing card  10 . As in the embodiment of  FIG. 6 , the distribution may be controlled or uncontrolled, deliberate or un-deliberate to uniquely identify the rank, and/or suit, and/or playing card  10 . 
         [0038]      FIG. 8  shows a gaming environment  50  including a gaming table  52  operated by a dealer  54  and at which players  56  play. The game table  52  may include a number of areas known as bet circles  58  for placing wagers represented by chips  60 . The dealer  54  may deal playing cards  62  from a card shoe  64  which holds one or more decks of cards, typically up to eight decks. The dealer  54  may pay winning wagers using chips taken from a chip tray  66  and/or collect losing wagers by retrieving the wagered chips  60  and placing the retrieved chips in the chip tray  66 . The dealer  54  may optionally return playing cards  62  collected at the end of each round or game to an optional discard shoe  68 . Casinos typically define an order in which playing cards  62  are collected. This allows the individual hands to be recreated if a player later challenges the outcome, even after the playing cards  62  are collected. 
         [0039]    An automated wireless system  70  may wirelessly monitor playing cards and/or chips. The system  70  includes a computing system  72  controllingly coupled to a transmitter  74  and receiver  76 . In some embodiments, the transmitter  74  and receiver  76  may be formed as a single transceiver. The transmitter is coupled to one or more antennas  78 , and the receiver is coupled to one or more antennas  80 . For example, the transmitter  74  may be coupled to an antenna  78  positioned in or on the gaming table  52 . The receiver  76  may be coupled to an antenna  80  positioned in, or on, the gaming table  52 . The antennas  78 ,  80  may be positioned at a central location, or respective antennas  78 ,  80  may be positioned proximate each of the bet circles  58 , respectively. Antennas  78 ,  80  may also be positioned in the card shoe  64 , chip tray  66 , and/or discard shoe  68 . The system  70  may include a wedge or similar device between the computing system  72  and the transmitter  74  and/or receiver  76  for converting RF signals into data suitable for processing by the computing system  72  (e.g., converting RF signals into formatted ASCII data). 
         [0040]      FIGS. 9 and 10  show the card shoe  64  including a plurality of playing cards  84  and a block or weight  86  for urging the playing cards  84  towards a slot  88 . A portion  90  of the card shoe  64  may be formed of a radio frequency impervious, resistant or absorbent material, thereby forming an RF barrier isolating all but one playing card from the antennas  78 ,  80  at a time. Thus, each playing card will be wirelessly interrogated as it is removed from the card shoe  64  by way of the slot  88 , without interference by the other playing cards  84  in the card shoe  64 . 
         [0041]      FIG. 11  shows a number of playing cards  10  according to an alternative embodiment where the position of the conductive material  26  corresponds to the rank  20  and/or suit  22  of the playing card  10 . For example, playing cards with the value of eleven or one (e.g., ACE) may carry the conductive material  26  in the upper left and lower right quadrants of the face  16  as illustrated in  FIG. 11 . Playing cards  10   b,    10   c  having a value of 10 (e.g., ten, Jack, Queen, King) may carry the conductive material  26  in the upper right and lower left quadrants of the face  16  of the playing card. Playing cards having other values  10   d  (two-nine) may not carry conductive material  26  or may carry conductive material  26  in other positions on the face  16 . 
         [0042]      FIG. 12  shows one of the playing cards  10   b  of  FIG. 11 , positioned in a playing card reader such as the card shoe  64  or discard shoe  58 . In this embodiment, the radio frequency barrier  90  isolates two quadrants of the playing card. The antenna  78  coupled to the transmitter  74  is positioned below the card  10   b  and barrier  90  to radiate both quadrants of the playing card  10   b  isolated by the barrier  90 . The antennas  80   a,    80   b  are positioned in respective quadrants, isolated by the barrier  90 . The antennas  80   a,    80   b  may be electrically coupled to respective receiver  76   a,    76   b  or alternatively to a single receiver  76 . Thus, interrogation via the transmitter  74  and antenna  78  may result in resonance of the conductive material  26  which would be detected by the antenna  80   a  and receiver  76   a,  but not detected by the antenna  80   b  and receiver  76   b  due to the barrier  90 . Thus, it may be determined whether the playing card  10  has a value of ten, or whether the playing card is an ACE having a value of eleven or one. This embodiment is particularly suitable for games of blackjack, but may be suitable for other card games with or without modifications which will be apparent to one skilled in the art. 
         [0043]      FIG. 13  shows a method  100  of wirelessly reading a playing card starting in step  102 . In step  104 , the transmitter  74  and antenna  78  transmit a radio frequency interrogation signal. In response, the conductive material  26  resonates at a characteristic resonance frequency corresponding to at least the rank/value  20  and/or suit  22  of the playing card. In step  106 , the receiver  76  and antenna  80  receive the response from the playing card  10 . In step  108 , the computing system  72  and/or wedge  82  signal process the response. In an optional step  110 , the computing system  72  decrypts the received response. In optional step  112 , the computing system  72  decodes the received signal or the decrypted signal. In step  114 , the computing system  72  determines the value and/or rank of the playing card  10  based on the received response. Additionally or alternatively, the computing system  72  may determine a serial number as part of determining the value and/or rank of the playing card  10 . 
         [0044]      FIG. 14  shows a method  200  of wirelessly identifying wagers starting in step  202 . In step  204 , the transmitter  74  and antenna  78  transmit a radio frequency interrogation signal. In step  206 , the receiver  76  and antenna  80  receive a response from one or more chips  60  representing a wager. The chips  60  may include conductive material  26  distributed or deposited in, or on, the chips  60  in a fashion similar to that of the playing cards  10  described above. Alternatively, since the chips  60  are typically much thicker than a playing card  10 , the chips  60  may include an RFID semiconductor chip or wafer and antenna structure. 
         [0045]    In step  209 , the computing system  72  and/or wedge  82  processes the received response. In optional step  210 , the computing system  72  decrypts the received response. In optional step  212 , the computing system  72  decodes the received and/or decrypted response. In step  214  the computing system  72  stores the response. In step  216 , the computing system  72  determines whether a timeout has been exceeded. If a timeout has not been exceeded, the method  200  returns control to step  206 . If the timeout has been exceeded, the computing system  72  determines the wager amount in step  228 . Control may then return to step  204  to identify further wagers. 
         [0046]    The methods  100 ,  200  may employ polling or other techniques common in the RFID arts for identifying individual playing cards  10  and/or chips  60  from groups of playing cards and/or chips. 
         [0047]      FIG. 15  shows a method  300  of monitoring a playing card game. In step  302 , a computing system  72  determines the contents of a bank or chip tray  66 . The contents of the chip tray  66  may be determined in a similar fashion to that of the wagers, employing one or more transmitters  74  and antennas  78  as well as receivers  76  and antennas  80  positioned on or approximate the chip tray  66 . 
         [0048]    In step  304 , the computing system  72  determines the number and size of the wagers. The computing system  72  may employ one or more transmitters  74  and antennas  78  as well as receivers  76  and antennas  80  positioned at or proximate the bet circles  58 . 
         [0049]    In step  308 , the computing system  72  determines the outcome of a wager. The computing system  72  may employ one or more transmitters  74  and antennas  78  as well as receivers  76  and antennas  80  positioned in or proximate the card shoe  64 , discard shoe  68  and/or player positions. Thus, the computing system  72  relies on the received responses to identify the values of the playing cards  10  and thus the value of the hands held by the players  56  and dealer  54 , and compares these values to determine outcomes. The computing system  72  may further employ a defined set of odds to determine the value of the payouts. 
         [0050]    In step  310 , the computing system  72  determines the contents of the bank or chip tray  66  in a similar fashion to that described in step  302 . In step  312 , the computing system  72  validates the takes and payouts by comparing the contents of the chip tray  66  determined in step  310  with that determined in step  302 . Discrepancies can be identified and appropriate notifications provided. 
         [0051]      FIG. 16  shows a method  400  of determining the outcome of wagers, suitable for performing some or all of step  304  of  FIG. 15 . The method  400  starts in step  402 . In step  404 , the computing system  72  determines the original sequence of the playing cards  10  in the card shoe  64 . For example the computing system  72  may rely on one or more transmitters  74  and antennas  78  positioned in or proximate the card shoe  64 . The computing system  72  can cause the transmitter to interrogate each of the playing cards either before the playing cards  10  are removed from the card shoe  64 , or during or after the playing cards  10  are removed from the card shoe  64 . 
         [0052]    In step  406 , the computing system  72  determines the number of players  56  in the game. For example, the computing  72  may employ one or more transmitters  74  and antennas  78  and one or more receivers  76  and antennas  80  to detect chips  60  at various bet circles  58 . The number of bet circles  58  having chips  60  indicates the number of players  56 . In optional step  408 , the computing system  72  determines whether the dealer  54  has blackjack. Blackjack is defined as the dealer  54  having an initial hand of two playing cards  10  with a total value equal to twenty-one. The computing system  72  may employ one or more transmitters  74  and antennas  78 , as well as one or more receivers  76  and antennas  80  positioned at or proximate the dealer  64  to interrogate the dealer&#39;s cards. In this respect the computing system  72  may alternatively employ the knowledge of the original sequence and the number of players  56  to determine the value of the dealer&#39;s hand. 
         [0053]    In optional step  410 , the computing system  72  interrogates the dealer&#39;s initial hand employing one or more transmitters  74  and antennas  78  as well as one or more receivers  76  and antennas  80  positioned proximate the dealer  54 . In optional step  412 , the computing system  72  verifies the deal and/or sequence of playing cards using an knowledge of the original sequence and the identity of the cards forming the dealer&#39;s initial hand learned from step  410 . 
         [0054]    In step  414 , the computing system  72  may optionally determine an ending sequence for the playing cards. The computing system  72  may employ one or more transmitters  74  and antennas  78  as well as one or more receivers  76  and antennas  80  positioned in or proximate the discard holder  68 . 
         [0055]    In step  416 , the computing system  72  determines the player&#39;s final hands. The computing system  72  may rely on a knowledge of the original sequence, the number of players  56  and the dealer&#39;s initial hand to determine the player&#39;s final hands. Additionally, or alternatively, the computing system  72  may rely on the knowledge of the ending sequence. In step  418 , the computing system  72  determines the dealer&#39;s final hand. In step  420 , the computing system  72  compares the value of the player&#39;s final hand with the value of the dealer&#39;s final hand for each of the players. The method terminates at step  422 . 
         [0056]    Although specific embodiments of and examples for the wireless monitoring system and methods are described herein for illustrative purposes, various equivalent modifications can be made without departing from the spirit and scope of the invention, as will be recognized by those skilled in the relevant art. The teachings provided herein can be applied to other wireless monitoring systems, not necessarily the exemplary blackjack wireless monitoring system described above. 
         [0057]    The various embodiments described above can be combined to provide further embodiments. All of the above U.S. patents, patent applications and publications referred to in this specification are incorporated herein by reference, in their entirety, including but not limited to U.S. Pat. No. 6,460,848, filed Dec. 30, 1999, entitled “METHOD AND APPARATUS FOR MONITORING CASINOS AND GAMING” (Atty. Docket No. 120109.401); U.S. patent application Ser. No. 09/849,456, filed May 4, 2001, entitled “METHOD, APPARATUS AND ARTICLE FOR VERIFYING CARD GAMES, SUCH AS BLACKJACK” (Atty. Docket No. 120109.402); and U.S. patent application Ser. No. 09/790,480, filed Feb. 21, 2001, entitled “METHOD, APPARATUS AND ARTICLE FOR EVALUATING CARD GAMES, SUCH AS BLACKJACK” (Atty. Docket No. 120109.403). Aspects of the invention can be modified, if necessary, to employ systems, circuits and concepts of the various patents, applications and publications to provide yet further embodiments of the invention. 
         [0058]    The system may employ a transceiver rather than separate transmitter and receivers, and may employ common antennas. The methods may include additional steps, eliminate steps, and perform the steps in different orders. The playing cards can include additional layers, including protective coatings. These and other changes can be made to the invention in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the invention to the specific embodiments disclosed in the specification and the claims, but should be construed to include all wireless monitoring systems to track playing cards and/or wagers. Accordingly, the invention is not limited by the disclosure, but instead its scope is to be determined entirely by the following claims.