MXPA98010547A - Measurement of charges in public telephones of an inalambr telephone system - Google Patents

Abstract

The present invention relates to the wireless system includes one or more public telephones (12) from which users can initiate calls. A mobile switching center (16) connects telephone calls initiated from wireless public telephones with external telephone systems (18), such as the public switched telephone network (PSTN). To measure the charges resulting from the telephone call in an external system, the external system transmits periodic measurement pulses (52, 54) to the mobile switching center. Each impulse represents a predetermined amount of money, associated with the telephone call. The speed at which the periodic pulses are transmitted to the mobile switching center depends on the current billing regime and can be affected, for example, by the day's sheet. Instead of sending all the measurement pulses to the wireless public telephone, which therefore consumes a portion of the bandwidth available for wireless telephone calls, the mobile switching center (16) calculates a billing rate at steady state from the measurement pulses, and then transmits only the steady state billing regime to the wireless public telephone (1

Description

MEASUREMENT OF CHARGES IN PUBLIC TELEPHONES OF A SYSTEM. WIRELESS TELEPHONE FIELD OF THE INVENTION The invention relates to wireless telephone systems and in particular, to public telephones connected to wireless telephone systems.

BACKGROUND OF THE INVENTION Wireless telephone systems that include, for example, cellular telephone systems and wireless local loop systems have become popular for private individual use. Recently, wireless telephone systems have been extended to include public telephones. Wireless public telephones can be configured as public telephones connected to conventional terrestrial lines, such as the public switched telephone network (PSTN), but the public wireless telephone transmits telephone call signals to a base station remora instead of directly over land lines. al-r-factory The remore system may include, for example, space-based satellites, cell-based stations or their peers. Public telephones are particularly desirable for use within areas that do not include conventional land lines, P1797 / 98MX including remote locations in the United States, as well as remote locations in developing countries. Public telephones can be used with certain advantages, even within areas with conventional land lines, to offer customers a choice between telephone companies offering wireless service within the area. Wireless public telephones are also ideal for use within commercial airlines, trains, trucks, ships and their peers, where conventional land lines are not available. However, problems arise when implementing public wireless telephones in terms of measuring the resulting charges made by the public telephone user. With a public telephone connected to a landline, the measurement is typically achieved when transmitting from the network, measurement impulses to the public telephone. Typically, the measurement pulses are short tones adjusted, for example, to 4000 hertz (Hz). The public telephone may include a filter to filter out the tone so that the user does not hear the tones during the telephone call. Usually, the public telephone is preprogrammed with some monetary value associated with each measurement pulse to allow the current resulting charges during a telephone call P1797 / 98MX can be calculated from the total number of measurement pulses received during the telephone call. Each measurement pulse can represent, for example, the value of one or two cents of the time of the telephone call. During peak hours, when the telephone call rate is higher, the measurement pulses are transmitted more frequently. During low hours, when the call rate is lower, the measurement pulses are transmitted less frequently. Typically, the user is required to insert a certain initial amount of money into the public telephone to initiate the telephone call. After this, while the telephone call is in progress, the public telephone receives the measurement impulses and the amount of money associated with each measurement pulse is deducted from the initial amount of money inserted. A screen can be provided to indicate to the user the surplus amount of money. Typically, also as the amount of money remaining decreases below the minimum threshold, probably one dollar, the user is provided with a warning message or something similar to indicate that the telephone call can be terminated automatically if no more money is inserted inside. of the public telephone. In many state-of-the-art public telephones, the user is not limited to inserting P1797 / 98MX only coins. Can be used, alternatively, debit cards with preprogrammed amounts of money. Alternatively, the charges of the telephone call may be billed to the receiving party or probably to a credit card account, telephone card account or the like. Certainly, some state-of-the-art public telephones do not accept any currency, but operate only with debit cards or another method that does not use coins. Although the above described measurement technique works effectively for public telephones connected to land lines, problems arise when trying to implement the same technology for wireless public telephones. With most wireless systems it is necessary to minimize the amount of information transmitted from the base stations to the remote cordless telephones, in order to maximize the capacity of the system. Avoiding the transmission of redundant or unnecessary signaling information is a way to reduce the total bandwidth consumed per call and thus maximize the capacity of the system. Many wireless public telephone calls may need to be transmitted relatively simultaneously within a wireless telephone system. The transmission of periodic measuring impulses within P1797 / 98MX each call of the public telephone, particularly during peak hours, consumes a significant amount of bandwidth, which affects the total number of calls that can be linked simultaneously. The problem is of particular interest within wireless systems that use digital transmission techniques such as code division multiple access (CDMA). For CDMA, the way to process voice signals makes it difficult to transmit voice signals with high frequency tones superimposed on them. In accordance with this, for a hypothetical wireless system that transmits measurement pulses to a public telephone it may be necessary to convert the pulses into data packets, such as the class packages used to transmit instructions and control signals, to overcome the packets of data that contains the digitized voice data. For wireless local loop systems using CDMA, in particular, the restrictions in the formatting of these packages can significantly affect the amount of bandwidth available for other signals such as instructions, control signals and digitalized signals. voice. Therefore, if additional data signals corresponding to the measurement pulses are transmitted through the full duration of a telephone call P1797 / 98MX to a wireless public telephone, the available amount of bandwidth for the corresponding voice signals can also be reduced significantly, probably by limiting the maximum possible quality of the transmitted speech signal. These problems can be even more significant with public phones mounted inside airplanes, ships or similar, where voice quality may already be limited by other transmission restrictions. The need to process periodic measurement signals through a complete telephone call can also impose an obstacle on the microprocessor, or on some other device when processing the different digital signals received from the remote station. Accordingly, it is desirable to provide an improved method and apparatus for executing public telephone measurement within a wireless telephone system incorporating one or more wireless public telephones and, to this end, aspects of the invention are described.

SUMMARY OF THE INVENTION In accordance with one aspect of the invention, an apparatus is provided for use with a wireless telephone system. The apparatus includes a mechanism for receiving P1797 / 98MX measurement signals from an external system representative of the billing charges for a particular telephone call, linked between a cordless telephone and an external system. The apparatus also includes a mechanism for terminating a steady state billing rate for the telephone call, by transmission signals and a mechanism for transmitting a signal to the wireless telephone, the signal being representative of the determined steady state billing regime. The aparate may also include a mechanism to detect a change in the steady state billing regime for the telephone call and to determine and transmit a new steady state billing regime. With this device, the measurement signals from the external system do not need to be sent to a wireless telephone. Rather, only an independent signal representative of the steady state billing regime needs to be transmitted. If the speed changes, then another independent signal is transmitted, the signal being representative of the new steady state billing regime. As such, fewer signals are transmitted to the wireless telephone system and less bandwidth is consumed than in traditional systems, which transmit all measurement pulses. In an exemplary mode, the telephone Wireless P1797 / 98MX is a public telephone configured to transmit and receive signals to and from a base station according to the CDMA protocols. The cordless telephone includes a mechanism for receiving signals representative of the steady state billing regime for the telephone call and mechanisms for using this regime to calculate the amount of charges resulting from the telephone call. The cordless telephone may also include a mechanism to present the amount of charges resulting from the telephone call to a user operating the cordless telephone. The use of relatively few stable rate billing signals instead of frequent and periodic measurement signals is particularly desirable in cellular or wireless systems. wireless local loop systems, because a significantly smaller amount of bandwidth can be consumed by the few stable rate billing signals instead of the numerous and periodic measurement signals. In accordance with this, more bandwidth is available for other signals. The additional bandwidth can be used to process additional telephone calls or to allow larger amounts of data to be transmitted during a telephone call. Therefore, depending on the implementation, the width Additional band P1797 / 98MX can allow improvement in voice quality over systems that require the transmission of periodic measurement pulses, or an increase in the total capacity of the system. In the exemplary embodiment of the CDMA wireless public telephone, the only measurement signals received by the wireless public telephone are billing rate signals which indicate a particular steady state billing regime. A first billing rate signal is received at the beginning of a telephone call. Additional billing rate signals are received only if the billing regime changes. In an alternative mode, the wireless public telephone initially receives digitized signals corresponding to individual measurement pulses until the steady state billing regime has been determined. The wireless public telephone then receives an independent signal of stable billing rate and no longer receives the periodic measurement signals. In other arrangements, additional or alternative signals may be provided, in accordance with the principles of the invention, to minimize or eliminate the number of measurement pulse signals required for transmission to the cordless telephone.

P1797 / 98MX With the invention, the above-stated general objective is achieved. Other objects as well as other features or advantages of the invention will be apparent from the accompanying drawings and the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS OR FIGURES Figure 1 is a block diagram of a wireless public telephone system configured according to the invention. Figure 2 is a timing diagram illustrating periodic measurement pulses that are transmitted within a conventional public telephone system. Figure 3 is a timing diagram illustrating the steady state billing rate signals that are transmitted to the wireless public telephone of Figure 1. Figure 4 is a timing chart illustrating an alternative signal sequence for transmission to the wireless public telephone of Figure 1, wherein both measurement pulses and steady state billing rate signals are used. Figure 5 is a flow diagram illustrating a method for processing stable rate billing signals of the type illustrated in Figure 3.

P1797 / 98MX Figure 6 is a flow diagram illustrating a method for processing stable rate billing signals of the type illustrated in Figure 4.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES With reference to the figures, the exemplary embodiments of the invention will be described below. The exemplary embodiments are described mainly with reference to block diagrams and flow charts. As far as the flowcharts are concerned, each block between the flowchart represents both a step of the method and an element of the apparatus executing that step of the method. In the present, the element of the apparatus can be known as a mechanism or a unit for executing the method step. As far as block diagrams are concerned, it should be noted that not all components necessary to complement the implementation of a practical system are always illustrated or described in detail. Instead, only those components necessary for a general understanding of the invention are illustrated and described. In addition, components that are conventional or that can be easily designed and manufactured according to the teachings provided herein are not described in detail.

P1797 / 98MX FIG. 1 illustrates a wireless telephone system 10 employing one or more wireless public telephones 12, one or more base stations 14 and a mobile switching center 16. Wireless public telephones can be mounted in established locations, such as buildings, or on city streets, or they can also be mounted on mobile devices such as airplanes, trains, ships or trucks. The mobile switching center 16 is connected by means of a ground line to an external system 18, which can be part or connect to a PSTN system. The wireless public telephone 12 includes a numeric keypad 20, an alphanumeric screen 22, a slot 24 for receiving a debit card, and a slot 26 for receiving change or any other type of coin. A user initiates a telephone call using a wireless public telephone 12, either by inserting an initial amount of coins into slot 26 or by inserting a debit card into slot 24. The amount of coins or any other type of monetary credit introduced. by the user it is presented on the alphanumeric screen 22. Alternatively, the user initiates the telephone call by identifying a credit card account or a calling card account for billing purposes using the keypad.

P1797 / 98MX numeric. In any case, the appropriate signals to initiate the wireless telephone call are transmitted from a public telephone 12 wireless to a base station 14, according to one of the variety of wireless transmission protocols including, for example, CDMA, multiple access frequency division (FDMA) and time division multiple access (TDMA). Subsequently, it can be assumed that the CDMA protocols will be used, but the principles of the invention are applicable to other types of wireless transmission systems, as well as to other non-wireless transmission systems. The signals transmitted by the wireless public telephone 12 are received at a base station 14 and sent to a mobile switching center 16 to connect to the external system 18. For this purpose, the mobile switching center 16 can convert the wireless telephone signals received from a base station 14 into conventional tone signals for use with the PSTN systems. The tone signals are sent to an external system 18 to interconnect with other telephones within the entire PSTN system, to terminate the connection with the telephone specified by the telephone number entered by the user of the wireless public telephone 12. Once the telephone call has been established, the external system 18 starts to P1797 / 98MX transmit periodic measuring pulses to the mobile c-mutation center 16, to be used in the identification of the number of charges resulting from the telephone call using the external system 18. Measuring impulses are short periods established for, for example, 4,000 KHZ. As described above, each impulse is representative of a predetermined amount of money. Every impulse can represent, for example, the value of used call for the amount of two cents of time. FIG. 2 illustrates an example of measurement set-h-pulses 50. An initial portion of pulses s - = repeats at a first periodic rate during period 52 of time. A second portion is repeated at a second periodic rate which is a little faster, damaging the period 54 of time. The difference in the measurement pulse rate occurs, for example, as a result of an increase in telephone call charges caused by a call transition in normal hours at peak hours. Within FIG. 2 the transition is presented at point 56. In one example, the time period pulses 52 are transmitted at a rate of about one pulse per second while the period 54 time pulses are transmitted at a rate of some other form. high, I rate 1.2 pulses per second. The highest speed P-3797 / 98MX for period 54 time pulses is representative of a higher cost of a telephone call as a function of time. The sequences of measurement pulses, like the sequence illustrated in FIG. 2, are transmitted from external ur-system 18 of FIG. 1 to the mobile switching center 16. In conventional public telephone systems, the measurement impulses are only sent to the public telephone, which calculates the charges for telephone calls directly from there. With the system of FIG. 1, however, the mobile switching center 16 converts the sequence of numerous repeated measurement pulses into a sequence of relatively few stable rate billing signals, which is illustrated in FIG. 3. More specifically, FIG. 3 illustrates a sequence 60 having a single pulse 62 of steady state billing regime associated with the time period 52 and a second pulse 64 of steady state billing regime associated with the period 54 of time. The pulses 62 and 64 are configured, for example, as digital bit sequences containing a binary representation of the billing rate of the corresponding period of time. For example, if the measurement pulses of the time period 52 of FIG. 2 represent, each, the value of two cents of time P1797 / 98MX and are transmitted one second apart, then the signal 62 contains a bit pattern representative of a billing rate of two cents per second or $ 1.20 per minute. Similarly, if the measurement pulses of the time period 54 of FIG. 2 are transmitted at 1.2 pulses per second, then the signal 64 contains a bit pattern representative of ur-billing regime of 2.4 cents per second or $ 1.44 per minute. Any coding technique can be employed from a wide variety, to encode the associated measurement regime within the steady state billing rate signals. The billing rate itself can be calculated by the mobile switching center 16, only by counting the number of measurement pulses received during a predetermined period of time, such as 10 seconds, and then averaging over the time period. Alternatively, the mobile switching center can only calculate the period of time that has elapsed between the center points of any two successive pulses. The prior art has the advantage that a more accurate time average billing rate can be calculated, which is relatively free of noise or other statistical errors. This last technique has the P1797 / 98MX advantage of allowing the billing regime to be calculated more quickly and recalculated with each successive pulse. In any case, the mobile switching center 16 transmits a steady state billing signal once the billing regime has been established. Then, the monitors of the mobile switching center 16 receive pulses to determine whether the steady state billing regime has changed. Once a change is detected, the switching-mobile center 16 calculates the new steady-state regime and generates a new coded steady state er-rate billing signal. The various operations executed by the mobile switching center 16 can be carried out using hardware, software, firmware or combinations thereof. The stable state signals are sent, coupled with other signals such as voice signals, to the base station 14 for transmission to the public telephone. Stable-state signals can be superimposed with voice signals and CDMA protocols. The mobile switching center 16 preferably filters the tones of the measurement pulses so that the bandwidth of the telephone call is not consumed by the measurement pulses and so that the user does not hear the measurement pulses. The public telephone 12 wireless receives signals P1797 / 98MX transmitted by the base station 14 and extracts the stable state signals thereof. Of the steady state signals, the public telephone calculates the amount of charges resulting from the telephone call as a function of time. For this purpose, the wireless public telephone 12 preferably includes a watch or any other time device. Initially, the wireless public telephone 12 calculates the total amount of charges resulting from the start of the telephone call and discounts that amount of the amount of money, or any other monetary credit, initially received by the public telephone. Screen 22 is updated to reflect the amount of money remaining. As the telephone call proceeds, the wireless public telephone 12 periodically deducts amounts of money from the remaining amount of money according to the amount of time spent and the steady state billing regime. The amount of monetary credit presented on the alphanumeric screen is updated. The wireless public telephone 12 also monitors received signals to determine if a new steady state signal is received and is representative of a new steady state billing regime. If so, the wireless public telephone 12 immediately calculates the additional charges using the new rate value of P1797 / 98KZ billing in steady state. If the new regime is higher than the previous regime, then the screen will reveal to the user that the charges are discounted more quickly. As the remaining amount of money or credit decreases, the wireless public telephone 12 can notify the user that the telephone call is about to conclude automatically. This can be executed, for example, by overlaying an audio tone on the voice conversation c by providing a special alphanumeric line within the screen 22. In either case, the user concludes the telephone call or adds an additional amount of money or monetary credit or allows the telephone call to terminate automatically. In this way, during the telephone call the wireless public telephone 12 receives only an occasional signal from the steady state billing regime. Certainly, if the billing regime of the external system 18 does not change during the telephone call, then the wireless public telephone 12 will receive only one signal independent of the steady state billing regime. Only one additional signal is received if the billing rate changes, as may occur during the transition from peak hours to non-peak hours. Therefore, only one or two steady state signals are received P1797 / 98MX during the phone call. This is contrary to conventional public telephone systems that receive each of the periodic measuring impulses. In accordance with this, considerable bandwidth is saved within the transmission system by limiting the number of signals that need to be transmitted. The reduction in bandwidth consumption is advantageous within wireless systems and, particularly, within wireless local loop systems, where the available bandwidth is already limited by other restrictions including the need to transmit instructions and control signals as well as voice signals. In the arrangement described so far, the mobile switching center 16 determines the steady state billing regime before transmitting any billing information signal to the wireless public telephone 12. In an alternative arrangement, the mobile switching center 16 initially transmits the measurement pulse signals to the wireless public telephone 12 until the steady-state regime is determined. Then, the mobile switching center 16 transmits the steady state signal and terminates the transmission of measurement pulse signals. An exemplary resulting pulse sequence 70 is illustrated in Fig. 4.

P1797 / 98MX Initially, a few signals 72 of periodic measuring pulses are sent to the wireless public telephone 12. Once the billing regime has been determined, a signal 74 of the steady-state billing regime of the type described above is transmitted. Following point 76 of transition to a new billing regime, the mobile switching center 16 again transmits some signals 72 of periodic measuring pulses until a new billing regime is reliably determined and then the mobile switching center 16 transmits another signal 76 of steady state billing regime. In an alternative arrangement, the wireless public telephone 12 is configured to calculate the resulting charges of both the measurement pulses and the steady state signals. The wireless public telephone 12 only switches from one calculation technique to the other, to the detection of the receipt of a steady state billing rate signal. The public wireless telephone 12 switches to the measurement pulse calculation method, once a measurement impulse signal is received. The measurement pulse signal 72 of FIG. 4 does not require tone signals identical to the tone signals of the pulses received from the external system 18.

P1797 / 98MX Certainly, depending on the restrictions of the wireless system, it may not be possible or desirable to transmit tone measurement pulses. In the exemplary implementation, the mobile switching center 16 generates digitally encoded signals to represent the pulses. The signals are similar to the digitally coded signals of the steady state, but are encoded with a different bit pattern to identify the signals as discrete pulses rather than as values of the steady state billing regime. As can be seen, a wide variety of coding techniques can be used. FIGS. 5 and 6 provide flow charts summarizing the two techniques described above. Both in Fig. 5 and in FIG. 6, the operations executed by the wireless public telephone 12 are shown on the left side, the operations executed by the mobile switching center 16 are shown on the right side. The operations shown are those related to the measurement of a telephone call linked from a wireless public telephone 12. Many other operations executed by the wireless public telephone 12 and by the mobile switching center 16 are not shown. First, with reference to FIG. 5, the 12 public wireless phone receives an initial amount of P1797 / 98MX monetary credit that is used to make the telephone call, step 100. Then, in step 102, the user enters the desired telephone number and the telephone call is initiated. The signals are transmitted to the mobile switching center 16, where in step 103, the telephone call is sent to the external system 18 through the terrestrial lines, such as the land lines of the PSTN. Then, in step 105, the mobile switching center 16 begins to receive the measurement impulses from the external system 18. In step 107, the mobile switching center 16 determines the steady state measurement rate from the received pulses, and in step 109, it encodes the steady state measurement regime as a digital signal. The digital signal is transmitted to the wireless public telephone 12 in step 111. Then, the mobile switching center 16 continues to receive the measurement pulses and repeatedly updates the steady state measurement mode by the newly received measurement pulses, step 113. If the new steady-state regime differs from the previous regime, step 115, then the instruction returns to step 109, wherein the mobile switching center 16 encodes the new steady-state regime as a digital signal for transmission to a telephone. 12 wireless public. If in step 115, the new regime does not differ from the previous regime, P1797 / 98MX then the instruction only returns to step 113 where the mobile switching center 16 continues with the recording of the newly received measurement pulses. Therefore, the instruction proceeds in a loop that includes steps 109-115, or only steps 113-115, until the telephone call ends. With respect to the wireless public telephone 12, after step 102, but before the wireless public telephone 12 has the opportunity to receive a steady state signal, the wireless public telephone 12 adjusts an internal stable state value for an omitted step value llß. The default value can represent, for example, the steady state billing regime for non-peak hours. In step 118, the wireless public telephone 12 calculates the resulting charges when using the steady state value. Up to this point, the wireless public telephone 12 tracks the elapsed time and multiplies it by the steady state value. The charges are deducted in step 120, from the initial amount of monetary credit and the remaining amount is presented. In step 122, the wireless public telephone 12 determines whether the stable state signal has been received from the mobile switching center 16. If not, the instruction returns to step 118 where the wireless public telephone 12 continues the calculation of the charges on P1797 / 98MX the basis of the regime of the original value of stable state omission. If, in step 122, where the internal value of the stable state is received, then the instruction proceeds to step 124, where the internal value of stable state is adjusted to the received value. The instruction then returns to step 118, where the additional charges are calculated by using a new steady state value. Steps 118-124 are executed in a loop until the telephone call is terminated. Of course, step 124 is executed only when a new stable-state digital value is received. As noted above, for many phone calls only a steady state value will be received during the telephone call. With reference to FIG. 6, the operations of the public wireless telephone 12 and the mobile switching center 16 for the alternative arrangement will be briefly described, wherein both the steady state signals and the measurement pulses are transmitted to a wireless public telephone 12. Many of the steps of the FIG method. 6 correspond to the steps described with reference to FIG. 5, and the descriptions of those steps will now be repeated. As in FIG. 5, an initial amount of monetary credit is received and the telephone call is initiated on the public wireless telephone 12, steps 200 and 202. The telephone call is connected to the ei P1797 / 98MX external system 18 and the measurement pulses are received by the mobile switching center 16, steps 203 and 205. After step 205, instead of immediately determining the steady-state measuring regime, the center 16 of mobile switching encodes the measurement pulses as individual signals and transmits those signals to the wireless public telephone 12, step 207. Then, in steps 209-213, the mobile switching center 16 determines the steady state measurement rate and encodes that regime as a digital signal and transmits the digital signal to the wireless public telephone 12. In steps 215 and 217, the mobile switching center 16 continues with the processing of the newly received measurement pulses to update the steady state measurement regime and to determine whether the updated regime differs from the previous regime. Steps 215 and 217 are executed in a loop until the new scheme differs from the previous one. At that point, the instruction returns to step 207 where the mobile switching center 16 begins to encode and transmit the individual measurement pulses. Then the new stable state measurement regime is determined and transmitted. Therefore, steps 207-217 or only 215-217 are executed on the link until the telephone call ends. During this time, the mobile switching center 16 transmits, from P1797 / 98MX alternative form, signals representative of measurement pulses or signals representative of steady-state billing regimes. For each change in the billing regime, the mobile switching center 16 transmits measurement pulses until the new billing rate can be terminated and then transmits only one signal independent of the new steady state billing regime. In typical implementations, no more than five or ten periodic measurement pulses are transmitted before determining the steady-state regime. With respect to the operations of the public wireless telephone 12, after step 202, the public wireless telephone 12 receives the individual measurement pulses, step 218, and calculates the charges thereof. In steps 220 and 222, the charges are deducted from the initial amount of the monetary credit received and the surplus amount is presented to the user. In step 224, the wireless public telephone 12 determines whether the digital signal of the stable state has been received. If not, the instruction returns to step 218. Otherwise, the instruction proceeds to step 226 where the wireless public telephone 12 calculates the additional charges when using the newly received steady state measurement regime. Additional charges are deducted from the amount P1797 / 98MX left over from the monetary credit and the resulting figure is presented in step 228. In step 230, the wireless public telephone 12 determines whether an additional measurement pulse indicating a switching to a new billing regime was received. If so, the instruction proceeds from step 230 to step 218, where the wireless public telephone 12 again calculates the charges using the measurement pulses better than the steady-state regime. If not, the instruction returns from step 230 to step 226 where the wireless public telephone 12 continues the calculation of the additional charges using the last steady-state regime. In this way, steps 218-230 are executed in a general loop until the telephone call ends. The above described are the exemplary embodiments of a public telephone measurement system that essentially reduces the number of measurement signals that need to be transmitted to a wireless telephone. Two specific exemplary implementations have been described here. Other implementations consistent with the principles of the invention can be developed. Although it was described mainly with reference to a wireless system that uses CDMA techniques. The invention can be used with other wireless systems that use others P1797 / 98MX transmission protocols and in wired systems. Certainly, the benefits of this invention can advantageously be exploited within any signal transmission system, where periodic metering pulses, similar periodic signals or pulses need to be transmitted. In accordance with this, the exemplary embodiment described herein should not be considered as limiting the scope of the invention. Rather, the invention must be exploited in a wide variety of other modalities both to achieve specific objectives and described here and to achieve other objectives and goals.

P1797 / 98MX

Claims (19)

1. NOVELTY OF THE INVENTION Having described the present invention,. it is considered as a novelty and, therefore, property is claimed as contained in the following EIVINDICATIONS 1. An apparatus for use with a wireless telephone system, the apparatus consists of: a mechanism for receiving measurement signals from an external system, representative of the billing charges of a particular telephone call, linked between a cordless telephone and the external system; a mechanism for determining the stable state of billing for the telephone call from the measurement signals; and a mechanism for transmitting a signal to the wireless telephone, representative of the stable billing status regime. The apparatus of Claim 1, further comprising: a mechanism for detecting a change in the stable billing status for the telephone call and for determining the new steady state billing regime. 3. An appliance for use in a cordless telephone, the device consists of: P1797 / 98MX a mechanism for receiving signals representative of a steady state billing regime for a telephone call linked between a public wireless telephone and an external system; and a mechanism to calculate the amount of charges resulting from the telephone call. 4. The apparatus of claim 3, further comprising: a mechanism for displaying the amount of charges resulting from the telephone call. The apparatus of claim 3, further comprising: a mechanism for receiving a monetary credit amount for the call; a mechanism to present a current amount of monetary credit available for the call; and a mechanism to discount the resulting charges during the telephone call from the current available amount of monetary credit. 6. The apparatus of claim 3, further comprising: a mechanism for receiving a plurality of individual measurement signals, each representative of an individual amount of monetary credit resulting from the telephone call, the mechanism for receiving the P1797 / 98MX individual measurement signals operate only during portions of the telephone call where a valid representative signal of the steady state billing scheme has not been received. The apparatus of claim 6, further comprising: a mechanism for receiving a signal that identifies that a previous representative signal of a stable state billing regime is no longer valid. 8. The apparatus of claim 3, wherein the external system is a public telephone switched network (PSTN). 9. The apparatus of claim 3, implemented within a wireless local loop telephone system. 10. The apparatus of claim 3, implemented within a cellular telephone system. The apparatus of claim 10, wherein the cellular telephone system utilizes code division multiple access data transmission (CDMA) protocols. 12. The apparatus of claim 3, implemented within a public telephone system accessible to the public. 13. The apparatus of claim 12, wherein P1797 / 98MX the wireless public telephone is in a fixed location. 14. The apparatus of claim 12, wherein the public telephone is mobile. 15. The apparatus of claim 14, wherein the public telephone is mounted within a mechanism for transportation. 16. A method for determining charges resulting from a telephone call connected to a wireless public telephone, the method comprising the steps of:, receiving a signal representative of a steady state billing regime for the telephone call; and calculate the charges resulting from the telephone call by multiplying the steady state billing regime by the duration of the telephone call. 17. A method for determining the charges resulting from a telephone call connected to a wireless public telephone, the method comprising the steps of: a) receiving individual measurement impulses, each representing a predetermined common amount of monetary credit charged by the call telephone; b) calculate the total amount of charges resulting from adding the common amount for each individual measurement pulse received; P1797 / 98MX c) receive a signal representative of a steady state billing regime for the telephone call; and d) calculate the resulting additional charges by multiplying the steady-state regime for an additional period of time resulting from the receipt of the stable-state billing rate signal and adding the resulting value to the previously calculated sum. 18. The method of claim 17, further comprising the steps of: receiving a signal indicative that the signal of the previous steady state billing rate is no longer valid, and repeating steps a) - d). The method of claim 18, wherein the signal indicative that the signal of the previous steady state billing rate is no longer valid consists of a single measurement pulse signal. P1797 / 98MX