Communication system and method

A system and method is disclosed for allowing communications between a base station and a group of mobile transceivers in a communications network used for a merchant facility.

FIELD OF THE INVENTION

The present invention relates in general to a communication system and method. It more particularly relates to such a system and method for use as a communication system by a commercial establishment such as a quick service restaurant, bank or other merchant.

BACKGROUND ART

There is no admission that the background art discussed in this section legally constitutes prior art.

Commercial establishments, such as quick service restaurants, banks, coffee shops or similar locations provide service by enabling people to drive their automobile or other vehicle or walk up to a communication service point without requiring them to leave the vehicle or enter the building to perform a transaction. Conventionally, a speaker and microphone are located at the service point so that the customer can communicate with service people inside the building using these devices.

There have been a variety of such systems. For example, reference may be made to the following U.S. patents, which are incorporated herein by reference in their entirety:U.S. Pat. No. 5,512,891 DRIVE-UP STATION VEHICLE DETECTION SYSTEM AND METHOD OF USING SAME;U.S. Pat. No. 5,305,132 OPTICAL WAVELENGTH COMMUNICATION SYSTEM AND METHOD OF USING SAME;U.S. Pat. No. 5,253,095 FULL DUPLEX COMMUNICATION SYSTEM AND METHOD OF USING SAME;U.S. Pat. No. 5,203,017 METHOD AND APPARATUS FOR ESTABLISHING WIRELESS COMMUNICATION WITH MULTIPLE CUSTOMER STATIONS;U.S. Pat. No. 4,882,770 WIRELESS OPTICAL COMMUNICATION SYSTEM;U.S. Pat. No. 5,590,407 DRIVE THROUGH WIRELESS ORDER TAKING SYSTEM;U.S. Pat. No. 6,067,294 WIRELESS COMMUNICATION SYSTEM AND WIRELESS COMMUNICATION APPARATUS; ANDU.S. Pat. No. 6,044,268 SYSTEM AND METHOD FOR PROVIDING INTERCOM AND MULTIPLE VOICE CHANNELS IN A PRIVATE TELEPHONE SYSTEM

In the past, the communications between the service point and the service personnel located in a building have been accomplished by hard-wired half-duplex intercom systems. A service person was required to walk to an intercom station and press a button to talk to the customer and then release the button to hear the customer. This arrangement prevented the service person from moving around the work area to multi-task while still talking to the customer. Moreover, the customer could not talk to the service person when the service person was talking, thereby all too frequently causing confusion and not always completing a transaction accurately. In addition, other service personnel could not listen to the conversation unless they happened to be near the intercom station.

In order to enable the personnel to have more freedom of movement during conversations with customers, a wireless half duplex analog communication system was successfully implemented. The speaker and microphone at the service point were hard wired to a base station inside the building. The service personnel wear or otherwise carry small mobile transceivers and headsets to communicate to the base station and thus to the customer. This arrangement enabled the service person to multi-task, while talking and allowed others to listen in on the conversation so they could help with the service function. This implementation still required the service person to press a button to talk and release the button to hear. Also, even though several service persons were wearing transceivers and listening, only one person could talk at a time or radio interference could prevent all communications under some circumstances.

For the purpose of facilitating the communication, a wireless full-duplex analog communication system was introduced. This full duplex system uses separate transmit and receive radio frequencies and antennas so that full-duplex conversations were possible. The base station transmits on frequency F1while the mobile units received on frequency F1. Conversely, the mobile transceivers transmit on F2and the base station receives on F2. This full duplex system enabled transmissions by only one mobile transceiver at a time to prevent radio frequency interference but enabled full duplex communications between the base and the customer to achieve an improved level of accuracy in the communications.

To provide the ability to have more than one mobile unit transmit simultaneously, several base station receivers were used. Within the base station, received audio signals were combined to provide the intercom function between all mobile transceivers. The base station used one transmitter to re-transmit all audio to all mobile transceivers to produce the intercom function where all service personnel could hear all conversations. Thus, the system successfully provided full duplex communication as well as enabling the capability to have two or more service personnel talk simultaneously. Moreover, if the business using this full duplex communication system had more than one service point, separate base stations and frequencies were used to service all lanes of traffic.

The detailed description is arranged according to the following outline:

According to certain disclosed embodiments of the invention, there is provided a system and method for establishing a service point communication link between a service point used by a customer and a base station. A wireless communication link is established between the base station and a service person using a mobile transceiver to link with the service point communication link to enable the customer and the service person to communicate for initiating a transaction. A wireless communication link is established between the base station and another service person using another mobile transceiver to link with the communication link between the customer and the service person so that the service person and the customer can communicate with one another.

According to yet another embodiment of the invention, there is provided a system and method for establishing a service point communication link between a service point used by a customer and a base station. A wireless communication link is established between the base station and a service person using a mobile transceiver to link with the service point communication link to enable the customer and the service person to communicate for initializing a transaction. A wireless independent communication link is established between at least two other service people using other mobile transceivers to enable the other service people to communicate with one another independently of the communication between the service person and the customer.

According to yet another embodiment of the invention, an intercom communication system and method enables the establishment of a service point communication link between a service point used by a customer and a base station. A wireless communication link is established between the base station and a service person using a mobile transceiver to link with the service point communication link to enable the customer and the service person to communicate for initiating a transaction. A wireless communication link is established between the base station and another service person using another mobile transceiver to enable another service person to broadcast a communication to other service people independently of the communication between the customer and the service person. Broadcast communication links are established between the base station and other service person mobile transceivers to enable another service person to communicate simultaneously with the other service people.

According to the disclosed embodiments of the invention, by using a time division duplex (TDD) full-duplex arrangement, communications can be carried out on a single radio frequency with a single antenna, thereby reducing cost, hardware complexity and interference. If the TDD switch rate is sufficiently fast as compared to human perception, then there is a perception of simultaneous transmit and receive.

According to the disclosed embodiments, in using time division multiple access (TDMA) only one radio frequency may be used to handle multiple simultaneous transmissions using only a similar amount of hardware as a conventional half-duplex radio system. TDMA combined with TDD enables multiple simultaneous transmissions and full duplex communications for all transmissions without the need for multiple receivers and antennas on a single radio frequency.

Moreover, the digital system according to the embodiments of the invention enables communications employing a single base station radio to accommodate a plurality of service lanes. The digital system of the disclosed embodiments can route signals to a specific mobile transceiver unit that all other units do not hear. The digital system of the disclosed embodiments allows a private connection between two mobile transceiver units that is isolated from the intercom network. By use of digital communications, substantially any number of messages can be routed by a large variety of ways without changing hardware.

According to the disclosed embodiments, there can also be full duplex digital data communications simultaneous with voice data between the base station and any mobile transceiver unit. Either the base station or the mobile units can initiate data connections. This data path can facilitate control functions between the base station and mobile units in a large variety of ways or act as simply a conduit through which data can travel in a full-duplex mode of operation between a terminal connected at the mobile transceiver unit to another terminal connected at the base station.

According to the disclosed embodiments, one result of being able to send data signals with the voice signals allows the following scenario when using customer detection. When a customer is detected at the service point, a detection signal causes the base station to transmit a data signal to at least one mobile unit and causes it to go into the transmit or talk mode. Then when the customer leaves the service point and the customer detection indicates no customer, the base station transmits a data signal to the mobile unit to stop transmitting and return to listen mode. In this scenario, the service person may not be required to press any buttons to establish and break communications with the service point. This operation may be substantially or even fully automatic and requires little or no physical action from the service person.

With a digital system according to the disclosed embodiments of the invention, the voice and/or data transmissions may be encrypted for security to prevent (or at least reduce the possibility of) unauthorized listening. The disclosed digital systems may also include frequency hopping spread-spectrum, or direct-sequence spread-spectrum to prevent or to at least greatly reduce interference and further secure the radio link.

General System Description

Referring now toFIG. 1, there is shown a wireless communication system10, which is constructed in accordance with an embodiment of the invention. The system10may be employed in a merchant facility such as a merchant building12having two service lanes1and2. A service point14is disposed in lane1, and includes a speaker18and a microphone21. A customer detector or sensor23such as a loop detector is disposed in lane1for detecting the presence of customers (not shown) for the system10.

A similar service point25includes a speaker/microphone27in lane2. A customer detector or sensor29is similar to the sensor23.

A main base station32receives communication from the service point14via a cable34, and it receives a customer present signal from the sensor23via a cable36. A slave base station38is coupled to the main base station32via a cable39for communication there between. A cable41provides audio communication between the service point25and slave base station38. A cable43provides a customer present signal in lane2via a cable43.

A radio transceiver44is shared by the main and slave base stations and is located in the main base station32. The transceiver may receive signals via a pair of antennas45and46. The transceiver44includes a transmitter48and a receiver50.

The pair of antennas45and46may be employed for signal diversity. However, it is to be understood that a single antenna may also be employed.

A service person mobile transceiver51is carried or worn by a service person in the merchant building12to facilitate communications with a customer (not shown) at the service points14and25. A pair of antennas generally indicated at52for the transceiver51may be used with a transmitter53and a receiver54for the transceiver51, and provides diversity as hereinafter described in greater detail. It should be understood that inFIG. 1the pair of antennas are shown diagrammatically as connected individually to the transmitter53and to the receiver54; however, either one of the antennas may be selected and used for either the transmitter or the receiver.

In use, once a customer in lane1, for example, moves opposite the customer detector23and the service point14, a customer can communicate via the speaker18and the microphone21to the service person mobile transceiver51. In this regard, a communication link is established between the service point14and the main base station32, and a wireless communication link is established between the base station32and the service person mobile transceiver51. Thus, the service person can communicate with the customer at the service point14to execute a transaction.

A manager service person mobile transceiver56is similarly equipped with a pair of antennas generally indicated at58, a transmitter61and a receiver63to establish a communication link with the base stations so that the manager service person can communicate with both the service person and the customer.

A similar service person mobile transceiver65is equipped with a pair of antennas generally indicated at67, a transmitter69and a receiver72to establish a wireless communication link with the base stations to facilitate communications with the other service people.

A like service person mobile transceiver74is similar to the mobile transceiver65, and includes a pair of antennas generally indicated at76, a transmitter78and a receiver81. As hereinafter described in greater detail, the service people can communicate amongst themselves in a variety of modes of operation.

Each one of the mobile transceivers includes a number of control buttons. Considering now the control buttons for the transceiver51, which are similar to the control buttons of the other mobile transceivers, an A1 button83, when actuated, provides an audio communication linked with the service point14of lane1. An A2 button85, when actuated, provides an audio communication link between the transceiver51and the service point25of lane2. A B button87, when actuated, provides a page audio channel for the mobile transceivers to the exclusion of the service points. A pair of increase and decrease volume buttons89and92control the volume of the audio signals. A power ON/OFF button94is provided to control the power to the transceiver.

Main Base Station

According to one embodiment of the invention, the base station shown inFIGS. 2 and 3may generally comprise the base radio transceiver44and two base audio main boards. These block diagrams show a dual lane configuration. One radio transceiver44supports two-lane operation in this implementation. It will become apparent to those skilled in the art that other arrangements and configurations may also be employed, such as a fully integrated single board arrangement.

Considering now the base main audio board, the main and slave base stations32and38have similar base main audio boards and therefore a description of only one will now be presented. Also the interface between the main and slave audio boards will now be described with reference toFIGS. 2 and 3.

Lane1microphone21is located at the service point14(FIG. 1) usually, inside a menu board or a speaker post. This microphone21is hardwired to the base station32inside the building12. The microphone signal is initially passed through a combined highpass and lowpass filter96. The filters eliminate high and low frequency components from the service point. This reduces the noise from vehicles and general background at the service point. After filtering, gain is applied by an amplifier98to establish a noise figure and provide enough gain for the following circuits.

After amplification the signal is applied to the noise and echo cancellation analog-to-digital converter (CODEC). A digital signal processor (DSP)103and the coder decoder (CODEC)101, which is an analog-to-digital plus digital-to-analog converter, form the noise and echo cancellation sub-circuit. After processing in this sub-circuit the signal is converted back to analog and passed through analog switch105.

A microcontroller107, based on customer detection, controls the analog switch105. If a customer is present at the service point, the sensor23signals the microcontroller107via a customer presence detection circuit109, and the microcontroller closes analog switch105. After closing analog switch105, the signal is amplified by a pair of amplifiers112and114to a level necessary for the base transceiver44. Amplifier112also sums together two other audio sources into the signal path for transmission. The signals may be supplied from a message repeater116and the alert tone caused by customer detection. These signals are combined and applied to the radio transceiver44for transmission to the various mobile transceivers used by service people.

After closing analog switch105, the microphone signal is applied to a ceiling speaker amplifier118through an analog switch121and the voice activated attenuator (VAA)123. Analog switch121is closed by a user controlled switch read by the microcontroller107. If the microcontroller detects that the user set this switch to on, then the microcontroller107closes the analog switch121and the microphone signal is heard on a ceiling speaker125.

The radio transceiver44receives signals from the various mobile radio transceivers worn or otherwise carried by the service personnel or service person. The transceiver44determines which channel of audio is being received, “A” or “B”. “A” audio channel includes the service point and all mobile transceivers. All service people hear everybody. “B” audio channel excludes the service point and includes all mobile transceivers. Only mobile transceivers can hear each other. If the received audio is “A”, then the transceiver outputs audio to an amplifier127to add the gain necessary for the following circuits. After the amplifier127, the signal is applied to a noise and echo cancellation sub-circuit generally indicated at129. The signal is converted to digital and processed. After processing, the signal is converted back to analog and sent to an analog switch132. Analog switch132is closed if the microcontroller107receives an “A” control signal from the radio transceiver44. An amplifier134then adds additional gain and the signal is applied to an automatic volume control (AVC)136. After adjustment by the AVC136the signal goes to amplifier138and out to the Lane1speaker18at the service point14(FIG. 1). The Lane1speaker18is located at the service point usually inside the menu board or a speaker post. The speaker is hardwired to the base station32via the cable34(FIG. 1).

The AVC136can adjust the audio level heard at the lane1speaker18if the ambient noise level at the service point changes. This helps comply with local noise ordinances. The AVC136monitors the incoming audio heard by the lane1microphone21at the amplifier98. The AVC136converts this signal into a voltage representing the average level of the incoming audio. A microcontroller (not shown) in the AVC136then adjusts the out going audio level up or down using programming code algorithm decisions based on measuring the incoming average level from the lane1microphone21. If the level at the service point increases, then the out going signal is adjusted up a prescribed amount. If the level drops then the out going signal level is adjusted down a prescribed amount. The number of levels of adjustment and the range depends on implementation. As an example, the present method contemplates using a 128 step digital potentiometer that can adjust over a range of ˜25 dB.

If the radio transceiver44detects “B” audio, it outputs audio to an amplifier141and an analog switch143. Amplifier141provides gain and analog switch143is controlled by the microcontroller107. The microcontroller107closes the switch143if the user has set an external routing switch to send “B” audio to the ceiling speaker amplifier118.

The VAA123cuts back the in coming audio from the lane1microphone21if it detects audio on the out going path. An analog switch145is closed if the microcontroller107detects that the user has selected the VAA function to be used. The amount of cut back may be adjusted by the user. Once set, the cut back may be fixed and may either be on or off. The user may also set the threshold at which the cut back occurs.

The message repeater116provides a means to record and playback up to two short messages. These messages can be routed to three locations by means of a set of three analog switches147,149and152. To record a message, the service person selects record and then talks into the mobile transceiver using “B” channel. When the service person releases the “B” button, the message repeater stores the message and stops the record mode. The service person then selects the desired routing of the message when played back. As indicated more fully inFIGS. 33,34and35, depending on what was selected, analog switch147,149or152or any combination can be closed by the microcontroller107and the message sent to the mobile transceiver, the ceiling speaker125or the lane1speaker18. The message is triggered by input to the microcontroller107. Customer detection normally triggers the playback. Also an external input to the microcontroller107different than customer detection can be connected to an external device and the message repeater triggered. The user can select which input triggers the message.

In the present embodiment, two messages may be recorded. The user may select which message is played and where it is routed. They may be played in consecutive order. However, the messages can be triggered at different times and by different events and routed to different locations independent of each other.

An alert tone circuit154may generate two distinct tones based on inputs from the microcontroller107. With reference toFIGS. 11,12and32, the tone trigger event is by customer detection through the microcontroller107. Customers on lane1may produce a gong sound that the mobile transceivers hear, that are listening to lane1. Detection on lane2may cause, for example, a beep sound to be heard by mobile transceivers listening on lane1. It is the same for the slave base station. There may be a gong sound for lane2and a beep sound for lane1when listening on lane2. The alert tone audio level may be user adjusted by means of a potentiometer (not shown). The user may also select whether the customer tone is heard on the ceiling speaker125and if they want it to repeat every 4 seconds or other time interval, until a mobile transceiver answers the call by pressing “A,” letting the microcontroller107know by means of the “A” talk signal from the radio transceiver44.

A base power supply156may employ a standard rectifier (not shown) and filter that produces ˜22 volts direct current (VDC) from an external alternating current (AC) input. If direct current (DC) is used then the rectifier passes the DC directly through with a small voltage drop. All other voltages may be derived from the 22VDC by means of linear and switching regulators. Light emitting diode (LED) indicators are provided for the user to see that all voltages are present for troubleshooting purpose.

The microcontroller107may control most of the base functionality and interfaces with the radio transceiver44, the user controls, the message repeater116, and all the analog switches used to route audio within the base station32. It also interfaces with indicators, the customer detector109and external inputs for the purpose of triggering messages.

Customer detection may be implemented by an external detector or a board plugged into the base station. The microcontroller107may accept input from either kind of device. The customer detector23used for detection may be buried in the ground at the service point and may be hard wired to the detector. Other type detectors may also be employed. The detector outputs a logic level signal for the microcontroller107. Interface circuits are used to scale the voltage to that used by the microcontroller107and to protect the microcontroller.

As shown inFIG. 3, the slave base station38is similar to a master or main base station32except that there is no separate radio transceiver. The connections between the main and slave are as follows:1 Customer detect input from the slave base station for master alert.2 Customer detect output to the slave base station for slave alert.3 A2 Talk, output from the main base station for slave indication.4 B2 Talk, output from the main base station for slave indication.5 Car2, output from the slave base station to the main base station. Slave TX control.6 Ground7 TX Audio 2, input from slave base station.8 Ground9 RX Audio A2, output to slave base station.10 RX Audio B2 or B1+B2, output to slave base station.
Base Transceiver

Considering now the base radio transceiver44as shown inFIG. 4, the radio transceiver44generally comprises approximately six integrated circuits plus other components. The chips are as follows:1. CODEC chip158that does the A/D (analog-to-digital (A/D) and digital-to-analog (D/A) conversion for “A” channel lane1and2audio.2. CODEC chip161that does the D to A for the “B” channel lane1and2audio.3. DSP chip163, that converts between linear pulse code modulation (PCM) and adaptive differential pulse code modulation (ADPCM) and routes and mixes audio.4. Baseband processor165forming a part of a chip167may contain the radio link layer controller and functional interface and user control support. The chip167also supports the serial data interface.5. Radio Frequency (RF) transceiver169may contain all functions necessary to send and receive voice data at radio frequency. In the disclosed embodiment, the 2.4 Giga-Hertz (GHz) Industrial Scientific and Medical (ISM) band, 2.4 GHz to 2.4835 GHz are used.6. A chip172contains the low noise RF amplifier for the receiver and the power amplifier for the transmitter.7. Other components are used to regulate voltages and provide the transmit-receive (T/R) switching and antenna selection. There is also a seven-segment single digit display174.

The single radio transceiver44may support both the main and slave base stations32and38(FIGS. 2 and 3). The radio transceiver44is installed in the main base station32and the cable39attached between the main base and the slave base permits slave base audio and controls to be fed to the radio transceiver44(FIG. 1).

Audio from either lanes service point microphone is processed by the main or slave base main audio board and is then applied to the transceiver CODEC (chip158). The signals are shown as lane1transmit (TX) (master) and lane2(TX) (slave). These analog signals are converted to digital bits by the CODEC chip158and fed to the DSP163. The DSP163formats the signals and combines them with any “B” audio as required. The DSP163then outputs the signals to the baseband processor165for transmission.

The baseband chip167implements the protocol used for the system10and controls all radio link functions using software and hardware state machines. The baseband chip167implements the encryption function. The baseband chip167also includes a microcontroller176and a microcontroller I/O178that implements all interface and user functions for the base radio transceiver44.

The radio communication link uses, time division multiple access (TDMA), time division duplex (TDD), frequency hopping (FH) and diversity antenna selection. Audio data is sampled and broken down into 10 millisecond chunks and sent at approximately 1.1 mega-bits per second. One time slot burst is approximately 500 microseconds at this rate. At the appropriate time an audio chunk is sent to the RF transceiver169for RF transmission. Because of the use of TDMA, the lane1TX signal is sent in one time slot and lane2TX signal is sent in another time slot. To implement TDD there are also corresponding receive time slots for these two signals. Each time slot is transmitted at a different frequency to implement frequency hopping. The radio link control protocol is conventional.

The RF transceiver169takes the high-speed data from baseband chip167and uses frequency shift keying (FSK) to modulate it directly onto the RF carrier. The modulated signal is then sent to chip172for amplification. After amplification, the high power signal is applied to the correct antenna using the RF switch settings determined in advance by the baseband processor165. The signal is radiated and then received by the mobile transceivers.

A system service person can talk back to the service point by pressing A1 or A2 on the mobile unit. This sends a signal to the base radio transceiver44. The signal is received in the appropriate time slot on the antenna selected during preamble. The switches are set to receive and connect the signal to low noise amplifier (LNA)181in chip172.

Chip172amplifies the RF signal and establishes the system noise figure for the receiver. The amplified signal is then applied to the RF transceiver169. The RF transceiver169down converts the signal to a 110 MHz IF and demodulates the FSK. The raw data is sent onto the baseband processor165.

The baseband processor165unpacks the data and sends it to the DSP163for routing and mixing. The DSP163finally sends the audio data to the CODEC158for conversion to analog audio. The analog audio is then sent to the base main audio board (either main or slave) to be routed to the service point speaker such as speaker18as previously described.

“B” channel audio originates at a mobile transceiver and is received in the appropriate time slot just as described above for the service point audio. The DSP163instead routes the audio to CODEC161for a D/A conversion so it can be used on the base main audio board for the ceiling speaker125(FIG. 2). Otherwise the “B” audio is combined in the DSP163with lane audio and sent back for retransmission to all other mobile transceivers so they can hear the service person transmitting on “B”. This audio is not routed to the service point.

All audio data is formatted into packets for radio transmission. Each packet contains the actual data and a number of information bits to describe the source and destination. There are also bits to describe whether this is “A” channel or “B” channel information and there are bits for synchronization. Finally there are also bits that are used to check the integrity of the data. All of this combines to allow the radio to route the data to the desired location.

The packet format is used to implement signal diversity for a more robust link. Time, frequency and space diversity are used by this radio transceiver. Time diversity is implemented by sending the same packet in two different time slots. The packet check bits are used to determine which packet is correct. Frequency diversity is implemented by frequency hopping. Each time slot is a different frequency as well as a different time. Space diversity is accomplished by selecting one of the two antennas45and46(FIG. 1) based on signal strength during packet preamble. This is done during the receive time slot and the selection is held during the next transmit slot.

Base Radio Transceiver Interface

According to the disclosed embodiment, the radio interface generally may comprise the following signals implemented using the microcontroller176of the chip167.1. A1 Talk, active when receiving “A” channel data from lane1mobile transceivers, used for logic and user display2 B1 Talk, active when receiving “B” channel data from lane1mobile transceivers, used for logic and user display3 Car1, lane1transmit control from base main audio microcontroller1074 A2 Talk, active when receiving “A” channel data from lane2mobile transceivers, used for logic and user display5 B2 Talk, active when receiving “B” channel data from lane2mobile transceivers, used for logic and user display6 Car2, lane2transmit control from base main audio microcontroller1077 Serial data input, serial data input for transmission along with voice8 Serial data out, serial data received separated from voice data9 Start registration, user sets the base to look for new mobile units and logs their information10 Auto hands-free override, user switch to prevent the use of auto hands-free mode by mobile transceivers11 B split, user switch to allow independent “B” audio between lanes or common “B” across both lanes12 Single lane/dual lane select, user switch to select mode of operation13 ID display, base radio assigns a unique ID to each mobile radio registered, user sees it here during registration process and at power up. This ID is used for addressing serial data and to send audio to a particular unit. Base station rejects any mobile transceiver not registered.
Mobile Transceiver

As shown inFIG. 5, the mobile transceiver such as the transceiver51(FIG. 1) may be worn or otherwise carried by the service person to communicate with the base station32or38and the service point.

The mobile transceiver includes three integrated circuits and some miscellaneous components. Operation of the mobile transceiver is similar to that of the base radio transceiver. The mobile transceiver is used with a headset (not shown) that plugs into the unit. The mobile transceiver could also be integrated with a speaker and microphone as a single unit. Also the mobile transceiver may be battery powered by a single cell lithium-ion battery (not shown). The service person controls are shown inFIG. 1.

Beginning at the microphone input lead183, the headset audio signal is applied to a CODEC185of a chip187and converted to digital bits. The audio is sampled and broken down into 10 millisecond chunks of data. Chip187formats these chunks into packets for transmission. Details of the packets are as described for the base station radio transceiver44.

Chip187includes a baseband processor189that may control all the radio link functions. As with the base station radio transceiver this radio uses TDMA, TDD, FH and diversity antenna selection that matches the base radio transceiver44.

Once the audio data is formatted, it is sent to the RF transceiver192for a burst transmission in the appropriate time slot. The bits are modulated onto the RF carrier using FSK modulation at ˜1.1 megabits per second (MBPS).

The signal then proceeds to a chip194and is power amplified. The high power signal from this chip194is conducted to the proper antenna of the pair of antennas indicated at52through the T/R diversity switches. The antennas may be printed on the circuit board and are internal to the mobile transceiver51, unlike the base station antennas, which may be external.

When a signal is received from the base station, it is conducted into the mobile transceiver through the antenna selected during preamble for best signal strength. The signal proceeds through the switches to the low noise amplifier in chip194.

The LNA provides gain and establishes the noise figure for the radio receiver. The signal is then conducted to the RF transceiver192where it is down converted to 110 MHz intermediate frequency (IF) and demodulated. The demodulated data is now passed to the baseband processor189of chip187.

The baseband processor189unpacks the data and strips off the packing bits. The audio data is then sent to the CODEC185to perform a D/A back to analog audio. The output of the CODEC185is applied to a speaker amplifier196to drive the headset speaker (not shown). This amplifier196may not provide any voltage gain, only power gain in order to drive a speaker at a high sound pressure level.

Chip187includes a microcontroller198and a microcontroller I/O201that perform the interface for all user functions including switches and indicators. Chip187includes nine I/O lines to interface with a keypad of up to 20 keys.FIG. 6shows a mobile transceiver keypad203(a matrix) keypad layout of control buttons. There are four row drivers and 5 column receivers. This creates a matrix of up to 20 possible keys. In addition to the previously described buttons, there are 10 digit numerical buttons generally indicated at207for enabling the service person to input the i.d. address of another mobile transceiver to make an intercom call.

There are two LEDs that can be either red or green that are used to show status for the service person. They are used to show power on, base sync, which lane, low battery and out of range. Status is also indicated by voice prompts stored in the baseband flash memory. The same states are indicated by voice playback. For example, low battery is indicated by “Change Battery” and red blinking LED.

Chip187also handles the serial data interface to allow data to be sent with the voice data. Voice data may not have to be present to use the data path.

The data path between the mobile transceiver51and base transceiver44works in the following manner. Either the mobile transceiver or the base station can initiate a data connection. A command is sent to the interface to open a connection to a specific ID address. Once the unit indicates a connection is open, data may be sent at a low bit rate. A high level protocol may be established in the system10that connects to these radio transceivers to control data flow and prevent overruns. This may not be implemented in the radio transceivers. The data connection is bi-directional and full duplex. Once the data communications are complete, a command is sent to the interface to close the connection.

Before a mobile transceiver can be used with a base station, it must be registered. A button is pressed on the base transceiver to open the system for registration and then the mobile transceiver is power up in a certain sequence to cause a registration with the base. The base station handshakes, stores data about the mobile transceiver, and assigns an ID to the mobile unit. In the present embodiment, up to 15 mobile transceivers may be registered to a given base.

Referring now toFIG. 7, at state207, the base station may not have a power switch. When power is applied to the audio board, the unit turns on. The power from the audio board supplies power to the base transceiver board and customer detect board. Upon power up, the system10initializes all hardware ports, and readies switches. Upon power-up, the system10clears RAM. All switches are overridden to allow the message to be heard in the head set and over the ceiling speaker such as the speaker125, the first three times it plays to the speaker service point. The base transceiver board powers up, reads switches and search for connections. Any optional customer detectors power up and initialize.

When power is removed from the Audio Board, the unit turns off. The audio board may discontinue supplying power to the base transceiver board, and customer detector. When the power is removed, the unit may stop functioning immediately. There may not be a delayed shutdown. There may not be a special sequence of events during shutdown. There may not be values saved to memory before shutdown.

In the normal operation at state209, as shown inFIGS. 7,8,9, and10, the mobile transceiver “A” button activates the outside speaker audio channel. The mobile transceiver “B” button activates the page audio channel. The A decode may activate the outside speaker audio channel regardless of the condition of the customer present line.

Referring toFIGS. 11 and 12, there is shown state diagrams for various operations of the base station in connection with the relationship between the main base board and the radio transceiver for the base station. The state diagrams include the customer detection alert tones sent to the transceiver. The normal operation may follow the requirements of the receive/transmit state machine diagram inFIGS. 11 and 12. The state diagram ofFIGS. 11 and 12relates to the radio frequency (rf) signal, audio and gong control.

FIGS. 11 and 12illustrate various representative operations of the base station. The following is a key to the symbols used inFIGS. 11 and 12:VEH_PRES—Customer present current laneVEH_DET_IN—Customer present other laneA_DEC—Signal to talk on current laneAudio [l]—Inbound audioAudio [c]—Inbound Calling AudioAudio [S]—Outside Speaker AudioGong [x]—Gong lane x (1-current lane, 2 other lane) CARI turn on TxVEH_DET_OUT—Signal to other lane that customer is present in current lane

Referring now toFIG. 32, there is shown a state diagram for various operations of the base main audio board “beep” function for the alert tones. These are alert tones when the base stations detect customers at the service points by means of the detectors23and29. A beep idle state222transitions to states224or226when a customer is present. Alert and reminder signals are generated at states227,229and232. An early warning signal may be generated at state234.

Referring now toFIG. 33, there is shown a state diagram for the base main audio board message repeater record operation. From the idle state236, a state238is entered where a first message may be ready to be recorded. The final message is recorded at state241. A second message may be recorded at states243,245and247.

Referring toFIGS. 34 and 35, there is shown another state diagram for the base main audio board message repeater playback operation as it relates to the user switches. The recorded messages may be routed by the user to locations based on customer detection or the alert inputs.

From a message repeater idle state249, alert messages may be played at states252and254. The delay time of the messages are determined on user switch settings as indicated at state256. The customer present messages are played at states258and261.

Considering customer processing, if there are two lanes, then two base stations may be used as shown inFIG. 1. One of the base stations such as the main station32with the transceiver may be assigned to lane1and the other without a transceiver may be assigned to lane2. In dual service point applications, two base stations may send customer present information between each other. The mobile transceiver may switch lanes to utilize whichever base station has a customer present. If there is only one lane, then only one base station is required, and that base station would be lane1. Beep selection may follow the process of the state diagram inFIG. 32.

Each mobile transceiver is assigned a specific transmit time slot when the service person selects to transmit. The base station may be used to control and route audio traffic between mobiles and the service point connected to the base station. Any mobile transceiver can talk to the base station at any time as long as there are free time slots. Certain data bits in the voice packets from the mobiles may determine audio traffic routing at the base station. Normally all mobile voice packets may be retransmitted from the base so all other mobiles can hear. This provides the means for intercom communications (referred to as “B” Talk). A mobile service person can also select to have his or her voice packets routed to the service point at the base station as well as be retransmitted. This provides the means for wireless to wired communications (referred to as “A” Talk). Voice audio from the service point at the base will be transmitted to all mobile transceivers along with any mobile packets set for retransmission. In effect the audio sources are “summed” to form a kind of “party line” where everyone hears both sides of all the conversations.

When the service person turns on the mobile transceiver, it may immediately search for its registered base station and establish a downlink without any other service person actions. The unit audio may be muted and may remain in receive only with an active downlink until the service person activates a talk button or the base detects a car. Status may be indicated by audible and visual indications. Refer to state diagrams ofFIGS. 8,9,10,36and37for an overall view of the mobile transceiver states and their interaction.

The following table provides a summary of the normal operation of the mobile transceiver firmware. Each description assumes service person is starting from a standby condition using lane1(primary service point).

SignalLineUseHands-free Mode OnHands-free Mode Off“A1”RequestsPush once to talk. AfterPush and hold to talk.connection toreleasing button talkingReleasing buttonprimary servicecontinues. Pushing andterminates uplink.point and all mobilesreleasing again terminateslisten that arethe uplink. With uplinkconnected toactive receiving a commandservice point 1.from the base station whena car leaves discontinuesthe uplink. No A1, A2 or Bbutton presses for ~10minutes when uplink isactive discontinues uplink. Ifauto uplink mode is set anda car is detected then themobile activates an uplinkautomatically and entershands free transmit as if A1were pressed.“B“RequestsPush and hold to talk.Same operation as HFconnection toReleasing button terminatesmodemobile serviceuplink. Overrides otherpersons & basemodes in process (except amain board as “B“manager connection) andaudio on base. Notdoes not re-initialize thoseeither service point.modes.“A2”RequestsPush once to talk. AfterPush and hold to talk.connection toreleasing button talkingReleasing terminatessecondary servicecontinues. Pushing anduplink. In single lanepoint and all mobilesreleasing again terminatesmode functions inon service point 2the uplink. With uplinkparallel with A1.listen.active receiving a commandfrom the base station whena car leaves discontinuesthe uplink. No A1, A2 or Bbutton presses for about 10minutes when uplink isactive discontinues uplink. Ifauto uplink mode is set anda car is detected then themobile activates an uplinkautomatically and entershands free transmit as if A2were pressed.Service personChanges Volume Up orSameearpiece audioDown respectively.level.“ON”/Turns Unit On andTurns unit on whenSame“OFF”Off Single Buttonpressed. Turns unit off ifheld for 2 seconds afterbeing on.
“A1” Button

“A1” button83(FIG. 6) activation allows the mobile service person to converse with the customer in lane1(service point1). The unit provides audible and visual indication. The “A1” button83is only used for connection to and talking on the primary service point (lane1).

ParameterConditionsPIT Mode singleIf the unit is in the “push-to-talk”or dual lane modemode, the “A1” button when pressedand held may cause the unit totransmit to, and activate the “A1”channel of the base station (servicepoint 1). If the “A1” button isreleased, the transmission may stopand the RF uplink terminates.HF ModeIf the unit is in the “hands-free” mode,upon pressing the “A1” button the unitmay transmit. After releasing the“A1” button, the unit may continue totransmit. If the “A1” button is pressedand released again, the unit mayterminate the uplink to service point 1on the release event. The uplink mayalso automatically terminate when thecar detect goes false.HF mode + auto uplinkIf a mobile is set to this mode, theuplink is automatically establishedwhen a car arrives. Otherwise itworks exactly as a mobile in HFmode.A mobile set to this mode requires nobutton presses by service person.
“B” Button

“B” button activation allows a mobile service person to talk to all other workers within the work area regardless of which service point they have selected. Service point1and service point2does not hear any “B” channel audio. The “B” button connects with the base station previously registered. All mobile transceivers synchronized to the base may hear the conversation when “B” is depressed; no matter, which service point has been selected by the mobile service person. The “B” audio mode may also be set so that “B” on service point1cannot be heard on service point2and vice versa.

ParameterConditionsPTT or HFThe ″B″ button, when pressed and held mayModescause the unit to transmit to, and activate the″B″ channel of the base station. The “B” buttonmay operate even though another mobile istransmitting on channel “A1” or “A2” (assuminga free time slot is available). Releasing the “B”button terminates the RF uplink. “B” talk isheard no matter which service point had beenpreviously selected with “A1” or “A2” buttons byother MOBILE TRANSCEIVER servicepersons. Pressing “B” overrides HF/autouplink for this MOBILE TRANSCEIVER anddoes not re-initialize after B is finished. “B”mode can also be set on the base so that “B”audio on service point 1 cannot be heard onservice point 2 and vice versa.
“A2” Button

“A2” button85(FIG. 6) activation allows the mobile service person to converse with the customer in lane2(service point2). The unit provides audible and visual indication. The “A2” button85may only be used for connection to and talking on lane2(service point2). However, when dual lane is turned off, the “A2” button85works in parallel with “A1” button83.

ParameterConditionsSingle LaneIf the base is configured in the single lane mode,Modeactivating the “A2” button may parallel the actions of“A1” operation.Dual LaneIf the base is configured for dual lane mode, theModemobile transceiver may change the audio connectionfrom service point 1 to service point 2. After that itfunctions like “A1”.If the mobile transceiver is in the “hands-free” modeand transmitting A1 uplink, the mobile transceivermay mute the microphone prior to changing servicepoint. Pressing and releasing the “A2” button mayestablish an A2 uplink connection to service point 2.The mobile transceiver may receive service point 2downlink after pressing and releasing the “A2”button.HF mode and auto uplink work the same as A1 butrelate to service point 2.
Mobile Transceiver Confirmation Tones

The mobile transceivers may produce confirmation tones during certain events as described below. These tones may be played into the service person earpiece speaker along with any other audio present.

EventTonePressing keypad 0-9 numbers onTone after each key pressManager mobileManager dial toneTone on until next keypress or time out
Voice Prompts in Mobile Transceiver Unit

The mobile transceivers may use voice prompts to indicate function and configuration as described in the following table. These are examples only, as other suitable voice prompts may also be used.

The mobile transceiver micro-controller firmware may retrieve the desired voice phrase from memory and combine it with audio being sent to the mobile transceiver to the mobile transceiver earpiece speaker when a prompt is to be heard. Tone or voice prompts may be audible by the mobile transceiver service person whether or not the mobile transceiver is actually receiving audio from the base link.

The voice data may be stored as individual words in the mobile transceiver memory (not shown). The memory area may accommodate word locations and associated pointer table. Additionally, a phrase pointer table may be allocated that may accommodate possible phrases. Phrases may be no more than five words in length.

Voice data may be changeable and uploadable. A file packed as HEX format may be used for this purpose.

Mobile Transceiver Hands-Free Mode

The following table describes the hands-free operation:

ParameterConditionsHFIf the unit is in the “hands-free” mode and the unit isStoptransmitting uplink, the unit may remain in the “hands-free” mode but end the uplink when a valid basecommand is received when the car detect goes false.HFIf the unit is in the “hands-free” mode and the unit isTimeouttransmitting uplink and A1, A2 or B has not been pressedfor a predefined number of minutes such as about 10minutes the mobile unit may stop transmitting uplink withno action required from the base or service person.HandsIt can be used in either single or dual lane modes. Thefree +user of this mobile does not have to do anything to talkautowith the service point. When car detection goes true theuplinkmobile may automatically establish an uplink to theservice point and transmit audio without any actions bythe service person. When the car detection goes falsethe base commands the mobile to terminate the uplinkand go to receive only. The cycle is repeated every timea car is detected. A fail-safe time out may beimplemented to terminate any uplink after some minutescontinuous connection. Pressing the opposite lane “A”button does nothing except terminate the link like handsfree in a single lane system. Pressing the opposite lane“A” button in a dual lane system only results in a Busyprompt until the button is released. Then link terminateson release like hands free. If the auto uplink enabledmobile has a “B” conversation and a car arrives, then the“B” conversation may be closed down and the “A”conversation may be setup. If an auto uplink mobile islinked and the service person wishes to use ″B″ then the″B″ function may override the auto uplink and it may notbe restored when “B” is released. The user of the autouplink mobile may have to press “A” again to reconnect“handsfree” if necessary.
Mobile Transceiver Configuration

According to the disclosed embodiment, the mobile transceiver may, for example, be configured by using combinations of button pushes, as explained in the examples in the following tables.

The HF ON mode is as follows:

ParameterConditionsSet HF ON ModePressing, for example, the “B” andbuttonsexclusively while turning on the unit mayconfigure the unit in the HF ON mode.HF ON State SaveThe status of this mode may be stored into theNV Memory immediately.HF ON ConfirmationThe unit may confirm a change in the mode.

The HF OFF mode is as follows:

ParameterConditionsSet HF OFF ModePressing, for example, the “B” and the“” buttons exclusively while turningon the unit may configure the unit in theHF OFF mode.HF OFF State SaveThe status of this mode may be stored intothe NV memory immediately.HF OFF ConfirmationThe unit may confirm a change in the mode.

The auto uplink ON mode for lane1is as follows:

ParameterConditionsSet Auto uplinkPressing, for example, the “A1” and the “Λ” buttonslane 1 ONexclusively while turning on the unit may configureModethe unit in the auto uplink ON mode. Also may, forexample, set HF on if not set.ON State SaveThe status of this mode may be stored in the base.ON ConfirmationThe unit may confirm a change in the mode.

To prevent service person confusion the base may have a switch setting to disable any auto uplink operation by any mobile transceiver. Moreover, if one mobile transceiver is set to auto uplink and a service person attempts to set a second mobile transceiver to auto uplink on the same lane, it may be denied by the base and voice prompt may be played by the mobile transceiver.

An auto uplink ON Mode for lane2is as follows:

ParameterConditionsSet Auto uplink lane 2 ON ModePressing, for example, the “A2”and the “Λ” buttons exclusivelywhile turning on the unit mayconfigure the unit in the autouplink ON mode. Also sets HF onif not set.ON State SaveThe status of this mode may bestored in the base.ON ConfirmationThe unit may confirm a change inthe mode.

To prevent service person confusion the base station may have a switch setting to disable any auto uplink operation by any mobile transceiver. Moreover, if one mobile transceiver is set to auto uplink and a service person attempts to set a second mobile transceiver to auto uplink on the same lane, it may be denied by the base and voice prompt may be played by the mobile transceiver.

The mobile transceiver may enter the registration mode only after the following sequence of buttons.

ParameterConditionsRegistrationPressing, for example, “B” while turning onthe unit may cause the mobile transceiver toenter registration mode. After “B” isreleased the registration process begins.Once registration is complete the unit maysave the information.State SaveThe mobile transceiver shall save theregistration information and use it every timethe mobile transceiver is powered up.ConfirmationThe unit may confirm registration functions.
Base Transceiver Operation

The base transceiver44provides the means for radio communication between service point14or service point27at the base station and the mobile units. The transceiver44is controls and routes intercom voice traffic between the various mobile units and two base service points. All communications are full duplex.

The base transceiver may support at least 10 uplink and 10 downlink time slots. During poor signal conditions or heavy interference, the base transceiver32may support dual slot diversity. If no time slots are available when a mobile transceiver attempts to establish a connection the service person may be alerted.

The base transceiver LED operation is as follows:

EventLED ActionAt initial power up, or all mobileBlink redtransceivers shut down, or no mobiletransceivers detected after a time out.After power up and at least oneSteady greenmobile transceiver is detectedNo slots, system busySteady RedDuring registrationBlink greenSuccessful registrationSteady green

The base transceiver display is used during registration or when a mobile transceiver has been turned on and has made a connection. Mobile ID numbers are written to the display.

The following table shows the various events:

EventLED ActionWhen the registration isShow Mobile ID untilcompleted successfullysomething else shall use the displayA MOBILE TRANSCEIVER hasShow Mobile ID untilmade a connection to the base.something else shall use the displayThe Base registration databaseShow “F” until something elseis fullshall use the displayThe registration has failedShow “—” until something elseshall use the displayThe base is open for registrationShow “o” (small o) untilsomething else shall use the displayThe base registration databaseShow “c” (a small c) untilhas been clearedsomething else shall use the displayAny other actionClear display until somethingelse shall use the display
Base Transceiver Normal Operation

All mobile transceivers may be capable of receiving voice traffic signals from any source in the network once they are synchronized to and authorized by the base. All links remain mute unless a mobile initiates the “A1”, “A2” or “B” talk functions or a car is detected at service point1or service point2.

After power up and during normal operation, the base transceiver may have a means to find new mobile units coming into the network and releasing mobiles leaving the network or powering down. It may be possible to turn on new mobile units at any time and have them recognized by the base transceiver. Such would assume previous registration.

Two logic signals are provided to the transceiver board interface that indicate whether or not a customer is detected at service point1or service point2. The transceiver board immediately un-mutes all mobile downlinks, sends one of two audio alert tones generated by the base main boards to all mobiles connected to service point1and/or service point2, and begins sending audio from the service point1and/or service point2microphone to all mobiles. The alert tones are summed into the analog audio input signal applied to the transceiver by either of the base main boards.

If a mobile service person presses either the “A1” button83, “A2” button85or “B” talk button87, a signal is sent to the base transceiver asking for an uplink. Once established, the base transceiver begins reception of audio traffic from the mobile(s) and routes it to the appropriate location defined by “A1”, “A2” or “B” functions. A mobile transceiver uplink may be established automatically upon car detection if a mobile transceiver has been set to the hands free+auto uplink mode.

If a mobile service person presses the “A2” button85, service point14is disconnected and the mobile transceiver is reconnected to service point25. Conversely, if “A1” is pressed service point25is disconnected and the mobile is reconnected to service point14. The “A1” and “A2” buttons function identically except they cause the audio connection to be toggled between service point14and service point25in dual lane mode. In single lane mode they function in parallel and there is no difference. Pressing the “B” button87directs audio only to mobiles and not any service point. As shown inFIG. 2, the base main board may direct “B” audio to a grill speaker also if so configured.

The base transceiver44may support two different “B” audio modes when the system is set for dual lane mode. One mode may allow any “B” audio to be heard by all mobile transceiver service persons regardless of which lane they are connected to. The second mode prevents “B” audio from a lane1mobile transceiver from being heard by mobile transceiver service persons on lane2and vice versa.

Base Audio Traffic Flow

The base transceiver44and the base main board control the traffic flow within the base station32and the communications network. The transceiver functions are confined to the radio link and traffic routing on the link. All analog audio routing and controls are functions of the base main board.

Referring now toFIGS. 13-27, various different possible traffic flow conditions are supported by the transceiver. These figures of the drawings show a variety of possible signal flows, although many others are possible. The base transceiver may support any combination of mobile transceiver connections between service point1and service point2even if they are not shown specifically in the following figures but the air connections are limited by available time slots. For example, when using a single service point, one “A” and three “B” connections might be required or four “B” connections in conference could be used.

As indicated inFIGS. 13-27, a mobile transceiver with an active uplink does not receive its own re-transmitted audio back from the base. This prevents or at least greatly inhibits echo for the service person.

One special case may require the use of a “manager mobile transceiver”. The “manager mobile transceiver can select to talk to any other mobile transceiver in the network and carry out a private conversation without anyone else able to listen. It uses the base to coordinate this function and uses available time slots. The limitation on air interfaces is still imposed. However, the manager connection may have priority. If a manager requests a connection and at least one slot is available, the base station32may terminate any lower priority traffic to make room for the manager connection.

As an example, to make a connection, the manager presses the “#” key (FIG. 6) and hears a dial tone. Then the manager presses the two digit mobile transceiver ID. This is entered via a keypad containing numbers 0-9 unique to the manager mobile transceiver. Using the ID number the base will route a direct one on one full duplex connection between the manager and a desired employee mobile transceiver. Any traffic being sent to the employee mobile transceiver may be terminated in favor of the manager connection if it has lower priority. The employee mobile transceiver may connect with the manager without any ring tone or any action by the employee. The employee mobile transceiver and manager mobile transceiver may only hear each other's audio because no other audio is routed to them during this type of connection. When the manager presses and releases the “#” button, the connection is broken and both mobile transceivers return to the network and function as usual. There is no timeout on a manager connection.

If the manager presses a mobile transceiver ID that does not exist or the mobile transceiver has an “A” connection, then the manager hears a voice prompt and the mobile transceiver shall revert to normal intercom operation.

The system10can register more than one manager mobile transceiver, and can support as many manager connections as time slots permit. Connection between two manager mobile transceivers may be permitted. Only the manager mobile transceiver that initiated the call can end the call. Manager mobile transceivers have all the functionality of a service person mobile transceiver when used for normal operations.

Examples of different audio combinations are shown and described inFIGS. 13-27. Referring now toFIG. 13, the customer arrives and the base station32transmits an alert tone and opens the audio link between the service point14and all mobile transceivers. Referring toFIG. 14, a basic connection with the mobile transceiver74, talking to the service point and all other mobiles are enabled to listen. Service point14is summed with mobile transceiver74audio for all of the listening mobiles.

As shown inFIG. 15, the mobile transceiver65presses button “B” and asks a question. All other mobiles hear mobile transceiver74and mobile transceiver65plus in bound service point14. No “B” audio is routed to the customer. Mobile transceiver74is also talking to service point14.

Referring toFIG. 16, the mobile transceiver74is talking to the service point14. The manager on mobile transceiver65also says something to the service point14. Service point14and all other mobiles hear everything.

Referring toFIG. 17, the mobile transceiver65presses “B” button87(FIG. 6) and asks a question. All other mobiles hear mobile transceiver65plus in bound service point14. No “B” audio is routed to the service point14.

As indicated inFIG. 18, the service point audio is not active. Two transceivers talk on “B.” Summing is required for all listening mobile transceivers.

As shown inFIG. 19, the mobile transceiver74is talking to the service point14and others are listening. The mobile transceiver65is a special transceiver that the manager uses. The manager selects transceiver56with a keyboard entry. When the base station32determines that a manager wants to talk with mobile transceiver56, it stops traffic to mobile transceiver56and routes only mobile transceiver56to transceiver65separate and independent from all other traffic. When the manager releases the connection, mobile transceivers revert to normal operation.

As shown inFIG. 20, the service point14is active and mobile transceiver74is talking to the service point14. Two mobile transceivers are also talking on “B.” Summing is required for all listening mobiles. Service point14does not hear “B” mobiles. All mobiles hear everything.

Referring toFIG. 21, the mobile transceiver65has its “B” button87pressed, to enable a question to be asked. All other mobiles hear mobile transceiver65. Service point14is not active. No audio summation is required.

As indicated inFIG. 22, the mobile transceiver65has its “A” button pressed for a test. All other mobiles hear mobile transceiver65and service point14is activated. Any mobile pressing “A” activates the service point14as though a car was detected. This may be used as a test mode. An employee at the service point14can talk to all mobiles like a customer.

As shown inFIG. 23, in the dual service point mode, the mobile transceiver51is talking to service point14and mobile transceiver74talking to the service point25. The mobile transceiver56is talking on “B” paging to another worker. “B” talk is heard by all mobiles. Service point14and service point25communications are independent and not heard by the other.

Referring now toFIG. 24, there is shown the dual service point mode, where a mobile transceiver51and mobile transceiver56are talking on the “B” page channel. “B” talk is heard by all mobiles. The mobile transceiver74is talking to service point25. Service point14and service point25communications are independent and not heard by the other.

Referring now toFIG. 25, there is shown the dual service point mode. where the mobile transceiver56and the mobile transceiver74are talking on the “A2” channel to service point25. Mobile transceiver51is talking on “B” channel.” “B” talk is heard by all mobiles. Service point14and service point25communications are independent and not heard by the other.

Referring now toFIG. 26, there is shown the dual service point mode, but without service point activity. The mobile transceiver51and the mobile transceiver56are talking on the “B” page channel. “B” talk is heard by all mobiles that were last connected to particular service point. B sum is disabled splitting the B channel between service points.

Referring now toFIG. 27, in a dual service point mode without service point activity. The mobile transceiver51and the mobile transceiver56are talking on the “B” page channel. “B” talk is heard by all mobiles. B sum is enabled combining both service point mobiles in the conversation.

The base transceiver firmware may provide priority to “A1” or “A2” connections (or both). When the transceiver determines one or both car detect signals go true and all slots are full, it may terminate lower priority connections to make room for an “A1” or “A2” connection as required (or both). Connection priority may be as follows:1) Service point connection2) Manager mobile transceiver connection3) Serial data communication4) B connection

For example, a manager connection may have higher priority than a serial data communication connection and an service point connection may have higher priority than both B and serial data communication.

To ensure that a prioritized connection may always be made, the base may reserve at least one available connection on the air interface when the appropriate condition is detected. Refer to the following table for the most common conditions and their effect on the number of available connections. This is an example assuming only 4 total connections are possible. There could be more or less total connections available in a system.

In the disclosed embodiment, the protocol may support at least 10 synchronous TDMA time slots for uplink and 10 synchronous TDMA time slots for downlink providing at least four simultaneous air interface connections and two audio broadcast channels, which transmits to the listening mobile transceivers.

This protocol may be capable of dual slot diversity during poor signal conditions or heavy interference. The protocol firmware may have the means to automatically use dual slot diversity when required.

The link protocol may contain the means for a mobile to disconnect from service point1and reconnect to service point2in a minimum amount of time. To go from one service point to another may be controlled by the mobile service person, by pressing either the “A1” button or the “A2” button to toggle the connection. A mobile transceiver uplink may be automatically established when a car is detected and a mobile transceiver is set for this function. All other transceivers function as usual.

The speech CODEC may use ADPCM, 32 Kbps compression. The protocol may support a one on one connection between a manager transceiver and any other transceiver in the network.

Serial Data Channel

The radio link protocol may support a low bit rate data channel on top of or in conjunction with the voice transmission.

The data from the serial data channel may be packed with the voice data using the tail bits in a portion of the voice packet. A separate electrical data input and output may be provided at the mobile and base end of the link. This is a bi-directional channel with an uplink and downlink.

The traffic flow cases for the data channel may be as follows.

1. Data input to the base transceiver may be sent to a specific mobile transceiver ID over a full duplex channel.

2. Data input to a mobile transceiver is sent over a full duplex channel to the base.

3. Data exchange between two mobile transceivers may or may not be supported as well as the broadcasting functionality.

Data to be sent over the data channel may be packetized by the user's external hardware and have a length and format to match the defined requirements of the data channel.

As shown inFIG. 28, a data terminal such as terminals215and216may be coupled to a mobile transceiver such as the respective transceivers51and56, capable of sending and receiving data to and from another system, referred to as the external data system. The external data system217could be any system capable of sending and receiving data. For example, such system may include a sales system, an inventory system and others.

Packet routing will now be described with reference toFIG. 28. In order to target a unique device (mobile transceiver or the external data system217) all devices may have a unique identifier (ID). When sending a packet from one device to another, both the destination ID and source ID may be sent as part of the payload. This way the receiving device is able to respond to the sending device.

The mobile transceiver ID may be used as the identifier for the attached terminal.

Considering now the protocol used in the system, the protocol is a protocol suitable for serial communication. The protocol supports communication between devices such as a terminal or sale system, a computer system, as well as communication between a device and a task/application within the attached mobile transceiver or the base station.

Data Flow Control

Data flow control may be implemented in the upper layer protocols/applications, located in the attached devices, to ensure reliable data flow i.e. the flow control may be implemented at the data terminal and external data system.

Since voice (A1, A2) has priority over the serial data link, it may be released by the base if a higher priority activity emerges. However, an existing voice link may carry serial data in conjunction with voice and the link may remain active if the voice terminates (mute mic) before data transmission is complete. The converse is true if a data connection is active and voice is desired.

There may be four commands: request connection, release connection, connection open, connection closed.

As shown inFIG. 29, the sequence chart illustrates connection establishment and release initiated by the data terminal connected to the mobile transceiver #51.

FIG. 29illustrates the series of communication paths or links that may be established between the external data system217and the data terminal215via the mobile51and base station14.

As shown inFIG. 30, the sequence chart illustrates connection establishment initiated by the external data system217. The target mobile transceiver is transceiver56.

As shown inFIG. 31, the sequence chart illustrates connection timeout and reestablishment.

Base And Mobile Registration

The base and mobile transceiver firmware may contain the means to register and maintain information in memory about connections to be used. Both the mobile transceiver and base may provide the means to perform registration using the RF interface.

The registration is initiated by pressing the registration button on the base then the mobile transceiver may use a previously described button sequence at power up to initiate the registration request. Registration may prevent unauthorized connections to the base. System retries several times before fail. Base displays a fail character if registration fails. For example, it may be a character different than any ID number. There are a certain number of ID numbers. If all IDs are used, and the user wishes to replace a mobile transceiver in the system, the user may clear the registration data from the base by pressing clear and reset simultaneously and re-register all mobile transceivers including the replacement. Trying to register a mobile transceiver that was previously done may only cause the base to display the ID and close registration. No other action may be taken. The base may be able to perform all normal functions while simultaneously registering a mobile transceiver. Once a mobile transceiver has been registered to a base, it may connect to that base every time it is powered up and then proceed with normal operation without any action by the service person. The mobile transceiver and base may be able to store registration data even with power off. The access code used to identify units allowed to register may be stored in memory of the mobile transceiver and base transceiver44.

Lane #1could be a single lane operation as opposed to the double lane operation as shown inFIG. 1. The customer beep complies with the following parameters with regard to Normal operation.

If selected, the customer present beep may be sent to the ceiling speaker. If de-selected, the customer present beep may not be sent to the ceiling speaker.

If selected, the early warning beep may be sent to the ceiling speaker. If de-selected, the early warning beep may not be sent to the ceiling speaker.

If de-selected, the customer present beep may play only once. If selected, the beep may be set to repeat at periodic intervals until the belt-pac “A” button has been pushed.

If selected, the customer present beep may be enabled to play. If de-selected, the customer present beep may not be enabled to play.

If de-selected, then when the customer is present, the unit may generate the primary customer present beep and send the beep to the mobile transceiver earpiece. If selected, then when the customer is present, the unit may generate the secondary customer present beep and send the beep to the mobile transceiver earpiece. The duration of the customer present beep may be 1 second. When the customer present beep is finished playing, the inbound audio channel to the mobile transceiver earpiece is opened.

Typically Lane #2is only used if there is a dual lane application. The customer beep may comply with the following parameters with regard to Normal operation.

A customer present output may be generated, and sent to a second base station for dual lane applications. This output may be active upon customer arrival, and inactive when an A Talk is detected.

If selected, the customer present beep may be sent to the ceiling speaker. If de-selected, the customer present beep may not be sent to the ceiling speaker.

If selected, the early warning beep may be sent to the ceiling speaker. If de-selected, the early warning beep may not be sent to the ceiling speaker.

If de-selected, the customer present beep may play only once. If selected, the beep may be set to repeat at periodic intervals until the mobile transceiver “A” button has been pushed. A customer at the opposite base station may generate the customer beep of the opposite pitch in the first base station, which may repeat, for example, at periodic intervals until the A button is pressed for the opposite system. This beep may be summed in with any audio currently being routed in the first base station16.

If selected, the customer present beep may be enabled to play. If de-selected, the customer present beep may not be enabled to play.

If de-selected, then when the customer is present, the unit may generate the primary customer present beep and send the beep to the mobile transceiver earpiece. If selected, then when the customer is present, the unit may generate the secondary customer present beep and send the beep to the mobile transceiver earpiece. The duration of the customer present beep may, for example, be 1 second. When the customer present beep is finished playing, the inbound audio channel to the mobile unit earpiece is opened. Each base station may have a distinctly different customer present beep (high/low pitch or/and single/double beep).

In single or dual service point operations, either communication button “A1 or A2” is actuated for communication with the customer, and button “B” may be used for communication with other service persons utilizing mobile transceivers.

Considering full duplex mobile transceiver operation, the base transceiver complies with the following parameters with regard to Full-Duplex operation.

The A Talk signal from the base transceiver may cause the customer to hear the service person's voice and service person hears the customer's voice (two-way conversation). Everyone using a mobile transceiver hears the communication.

The B Talk signal from the base transceiver may cause other personnel using mobile transceivers to hear the voice in their head sets (not shown) only.

Considering now half duplex communicator operation, the base transceiver may comply with the following parameters with regard to half-duplex operation.

The A Talk signal from the base transceiver may cause the customer to hear the service person's voice. Everyone wearing or carrying mobile transceiver hears the communication for a one way conversation.

The A Talk signal from the base transceiver may cause the customer's voice to be heard in head sets of everyone wearing or carrying a mobile transceiver.

The B Talk signal from the transceiver may cause other personnel using mobile transceivers to hear a service person's voice in their head sets in conjunction with “A” audio if present.

Dual Lane

The base station does not recognize the difference between single lane and dual lane. The dual lane configuration generally comprises two base stations, one for each lane. Each base station may be configured for its own A talk. For example, lane #1base station uses A1 talk and lane #2base station uses A2 talk. B talk may also split between base stations as B1 and B2 talk. For dual lane “B” audio may be split between bases or summed for a system wide page by means of a setting on the transceiver board.

A1 talk signal from the transceiver may cause the main base station32to operate as described above (Full-Duplex/Half-Duplex). The base station38may not respond.

The B1 Talk signal from the transceiver may cause base station32to operate as described above (Full-Duplex/Half-Duplex). The base station38may not respond.

An optional mode switch may be used to prevent the customer present signal being sent between bases in dual lane configuration—dual operators. Service person on lane1may not hear customer present tone from lane2. The converse may also be true.

Customer Detect

The customer detect operation may comply with the following parameters with regard to normal operation. The base station may contain up to two customer detectors. The detect signals are connected to the base CPU. One of these signals may be used to detect the presences of a customer at the service point and is processed by the CPU. The second customer detector may only have a relay output for external connection. The items described below are related only to the primary customer detector.

On the arrival of a customer, the customer detect signal may be sent to the transceiver. On the departure of a customer, the customer detect signal may be discontinued from the transceiver.

Message Repeater

The message repeater may comply with the following parameters with regard to normal operation. If the message switch is set to ON, and a customer arrives, depending on the switch arrangement, one of the two messages could be played, as outlined in “PLAY MESSAGE”.

If the message repeater is playing a message at a service point, triggered by customer arrival and the customer departs, the message may stop playing. If the message repeater is playing a message to speakers other than a service point, such as the speaker18and a new signal for a message to be played at the service point occurs then the current message may stop playing and the new message may begin playing.

Speed Team Operation

Speed-team operation is used during high-volume times. A service person using the mobile transceiver51may relay orders from outside into the merchant building12using the “B” button on the mobile unit. Placing the SPEED TEAM switch in the ON (in) position may disable the customer beep and inbound/outbound audio.

The base station enters the speed team operation if selected by the user.

The A1 button may not activate the outside speaker audio channel regardless of the condition of the customer present line. Thus the speaker and microphone in the service point such as a speaker post or a menu board may not be enabled.

The customer present beeps may be disabled.

The means to connect an optional remote ON/OFF switch that can be located away from the base enclosure for easy access may be provided. It operates in parallel with the on-board switch located on the base enclosure.

In customer processing, the customer arrival beep may be ignored. In single or dual service point operations, mobile unit button “A” may be ignored. Mobile unit button “B” is for communication with other service people using mobile transceivers.

Considering full duplex mobile transceiver operation, the mobile unit may comply with the following parameters with regard to full-duplex operation.

The A talk signal from the transceiver may be ignored, while in speed team mode. The B talk signal from the transceiver may cause other personnel using mobile transceivers to hear voice in their head sets.

Considering half duplex mobile transceiver operation, the mobile unit may comply with the following parameters with regard to half-duplex operation. The A talk signal from the transceiver may be ignored, while in the speed team mode. The B talk signal from the transceiver causes other personnel using mobile transceivers to hear voice in their head sets.

Dual Lane

The base station may not recognize the difference between single lane and dual lane. The A1 Talk and A2 Talk signals from the transceiver may be ignored, while in speed team mode.

The B Talk signal from the transceiver may cause the base station to operate as described above (Full-Duplex/Half-Duplex). The other base station may not respond.

The message repeater may comply with the following parameters with regard to speed team operation. Messages may not be played at outside speaker while in speed team mode.

Messages may be able to be played at transceiver headset and grill speaker while in the speed team mode (trigger message from alert signal).

The built in message repeater may be used to issue a consistent message to the outside customer, grill speaker or mobile transceiver earpiece. The message repeater may store up to two different messages. A message may first be recorded using the B channel from the mobile transceiver microphone. The message repeater Idle state for record is the same message repeater Idle state for play messages.

The message repeater may comply with the following parameters with regard to the base. Each message may be able to be enabled/disabled externally by user. Refer toFIG. 34

Each message may be able to be routed to the service point, Grill speaker and the mobile transceiver.

Two messages may be able to be played sequentially. The service point takes priority over the other locations.

Messages may be able to be recorded from the mobile transceiver “B” channel.

When a message has completed, the base station may provide a short tone to notify the service person. Inbound audio may not be muted when tone is played. An ON/OFF control that can be changed by the manager may be provided for the end-of-message tone

Each message may have a separate trigger input. Activation of both messages may be possible from a single trigger.

Pressing the “A” button after customer detection may terminate the message repeater output to the service point.

The base station may have a connection that allows a remote record button to be located away from the base enclosure for easy access. It may operate in parallel with the on-board record button located on the base enclosure.

Recording Messages

Recording Messages may comply with the following parameters with regard to the base station. The message repeater may be enabled when either the red message or green message switches are ON and Record is pressed and released (FIGS. 34 and 35).

In the record messages idle mode, the RECORD LED may be OFF. If Record is pressed and released, system settings may be initialized for recording messages, then the ready for red message mode may be entered.

In ready for red message mode and pre-ready for green message mode, the RED LED may be ON. If B Talk is received from a mobile transceiver, system enters record red message mode. If Record is pressed and released again, system may enter the ready for green message mode. If (A Talk is received from mobile transceiver, or time in this mode is beyond MAX_TIME) system may enter Idle mode.

In recording red message mode, the RED RECORD LED may blink. If the message duration is exceeded during record, the RECORD light may stay on solid from the end of the message time, until the B button is released. If (A Talk is received from Communicator) system may enter Idle mode. When no longer receiving B Talk from a mobile transceiver, the system may save the voice message and enter Idle mode.

In ready for green message mode and pre-record presses mode. The GRN LED may be ON. If B Talk is received from mobile transceiver, the system10may enter Record green message Mode. If Record is pressed again (third time), enter Wait Before Exit mode. If (A_Talk is received from Communicator, or time in this mode is beyond MAX_TIME) system may enter Idle mode.

Recording green message mode. the GRN RECORD LED may blink. If the message duration is exceeded during record, the RECORD light may stay on solid from the end of the message time, until the B button is released. If (A_Talk is received from a mobile transceiver) system may enter the Idle mode. When no longer receiving B_Talk from a mobile transceiver, the system may save the voice message and enter Idle mode.

In wait before exit mode, the Record button may have been pressed 3 times, for example: The LED may now be OFF. After the release of the RECORD button, the Idle mode.

Play Message

Playing Messages may comply with the following parameters and state diagram inFIGS. 33 and 34with regard to the base station.

The message repeater may be enabled to play one of two messages when either the red message or green message switches are ON, and a customer present or alert signal event triggers the system10into play mode. The description of the states is found in the play state diagram ofFIGS. 33 and 34.

Red message control switch (1-4) may specify which gates may be enabled during the playing of red message. If routing switches are all OFF, then red message may be disabled. Green message control switch (1-4) specifies which gates may be enabled during the playing of green message. If routing switches are all OFF, then green message may be disabled.

The message repeater may play a message due to a “customer arrival” and red message enabled for “customer arrival” or green message enabled for “customer arrival”. If both red message and green message are enabled for “customer arrival”, then message playback may be toggled between red message and green message. The message repeater may play a message due to an “alert signal” and red message enabled for “alert signal” or green message enabled for “alert signal.” If both red message and green message are enabled for “alert signal”, then message playback may be toggled between red message and green message.

A message to the service point may have the highest priority. If a message is playing and not going to the service point, and another message arrives which is going to the service point, the first message may stop and start the message to the service point.

If selected the system10may allow inbound audio during the red message.

If selected, red message may be played to the mobile transceiver earpiece.

If selected, red message may be played to the service point.

If selected, red message may be played to the ceiling speaker.

If selected, red message may be activated by the customer present signal.

If selected, red message may be activated by the alert signal.

If selected the system10may allow inbound audio during the green message.

If selected, green message may be played to the mobile transceiver earpiece.

If selected, green message may be played to the service point.

If selected, green message may be played to the ceiling speaker.

If selected, green message may be activated by the customer present signal.

If selected, green message may be activated by the alert signal.

After a new message has been recorded, or after the base station has lost and regained power, the message may always be heard in the mobile transceiver head set the first three times the message plays.

Voice Activated Attenuator

The audio board incorporates a voice activated attenuator (VAA). The VAA may comply with the following parameters with regard to the base station.

If selected, the VAA may sample the service point speaker volume and reduce the inbound audio volume to help prevent or at least to reduce feedback and outbound audio from over driving the inbound audio amplifiers.

Automatic Volume Control

The audio board incorporates an automatic volume control (AVC). The AVC may comply with the following parameters with regard to the base station. The AVC may provide the automatic volume control of outbound audio to the service point speaker to aide in noise abatement.

AVC internal ON/OFF control may be provided. Noise cancellation may be incorporated on the audio board.

If selected, the noise cancellation may be on. The base station may provide the ability to physically bypass the canceller.

The selection switches in combination may provide the ability to change the noise reduction level from maximum to minimum.

Base Audio Main Board Indicators

The light emitting diodes (LED) may comply with the following parameters with regard to the audio board. An LED may be provided for the 12 VDC. An LED may be in the on state when power is on.

An LED may be provided for main 22VDC. The LED may be on when the base power is on. An LED for the “A” Talk may be provided and may be on when the A Talk signal is output from the base transceiver board.

An LED may be provided for the “B” Talk and may be on when the B Talk signal is output from the base transceiver board. An LED may be provided for the customer present and may be on when an optional internal or external customer detector signal is present.

An LED may be provided for the message record and may be normally OFF. When the unit is ready to record red message, the LED may be on with the color RED in the steady state. When the unit is recording red message, the LED may be flashing RED. When the unit is ready to record green message, the LED may be on with the color GREEN in the steady state. When the unit is recording green message, the LED may be flashing GREEN.

An LED may be provided for the heartbeat. The LED may blink about twice every second.

An LED may be provided for the 5 VDC. The LED may be in the on state when power is on.

An LED may be provided for the 5 V transceiver voltage. The LED may be in the on state when power is on.

Configuration

The base main audio board user switches may comply with the following parameters with regard to the audio board.

A switch is provided to enable the voice activated attenuator (VAA). When the switch is in the ON position, VAA may be on. When the switch is in the OFF position, VAA may be off.

A switch may be provided to enable noise cancellation. When the switch is in the ON position, the noise cancellation may be on. When the switch is in the OFF position, the noise cancellation may be off.

A switch or switches may be provided to select the amount of noise cancellation.

A switch may be provided to enable full duplex. When the switch is in the ON position, the unit may be in full duplex. When the switch is OFF, the unit may be in half duplex.

A switch may be provided to enable “A” at the ceiling speaker. When switch is ON audio is conducted to the ceiling speaker.

A switch may be provided to enable “B” at the ceiling speaker. When switch is ON audio is conducted to the ceiling speaker. Another switch enables Inbound at the ceiling speaker. When switch is ON audio is conducted to the ceiling speaker.

A switch may be provided to enable customer present beep at the ceiling speaker. If ON, the customer present beep may be sent to the ceiling speaker. If OFF, the customer present beep may not be sent to the ceiling speaker.

A switch may be provided to enable early warning at the ceiling speaker. If ON, the early warning beep may be sent to the ceiling speaker. If OFF, the early warning beep may not be sent to the ceiling speaker.

A switch may be provided to enable reminder beep. If OFF, the customer present beep may play only once. If ON the beep may repeat at periodic intervals until the mobile transceiver “A” button has been pushed. A customer at the opposite base station may generate the customer beep of the opposite pitch in the first base station, which may repeat at periodic intervals until the A button is pressed for the opposite system. This beep may be summed in with any audio currently being routed in the base station32.

A switch may be provided to enable customer present beep. If ON, the customer present beep may be enabled to play. If OFF, the customer present beep may not be enabled to play.

A switch may be provided to enable inbound audio while red message is playing. When enabled, the inbound audio may be allowed during red message playback. Alternatively, if OFF the inbound audio may not be allowed during red message playback.

A switch may be provided to enable red message transmission to transceiver. If ON, then red message may transmit to mobile transceiver when playing. If OFF, then red message may not sent to transceiver when playing.

A switch may be provided to enable red message transmission to service point speaker. If ON, then red message may transmit to service point speaker, such as speaker18when playing. If OFF, then red message may not play to service point speaker when playing.

A switch may be provided to enable red message transmission to ceiling speaker. If ON, then red message may transmit to Ceiling Speaker when playing. If OFF, then red message may not transmit to Ceiling Speaker when playing.

A switch may be provided to select the event that would trigger the playing of red message. If ON, then the alert signal may activate red message. If OFF, then the customer present may activate red message. For a complete description of the requirements, which trigger red message, refer to MESSAGE REPEATER.

A switch may be provided to enable inbound audio while green message is playing. When enabled the inbound audio may be allowed during green message playback. Alternatively, the inbound audio may not be allowed during green message playback.

A switch may be provided to enable green message to be sent to transceiver. If ON, then green message may be sent to transceiver when playing. If OFF, then green message may not be sent to when playing.

A switch may be provided to enable green message transmission to service point speaker. If ON, then green message may transmit to service point speaker when playing. If OFF, then green message may not transmit to service point speaker when playing.

A switch may be provided to enable green message transmission to ceiling speaker. If ON, then green message may transmit to ceiling speaker when playing. If OFF, then green message may not transmit to ceiling speaker when playing.

A switch may be provided to select the event that would trigger the playing of green message. If ON, then the alert signal may activate green message. If OFF, then the customer present may activate green message.

A switch may be provided to delay playing messages. If ON, then there may be a pre-defined delay before playing red message and before playing green message. If OFF, then a different pre-defined delay may be used before playing red message and green message.

A switch may be provided to enable beep swap. If OFF, then when the customer is present, the unit may generate the primary customer present beep and send the beep to the transceiver. If ON, then when the customer is present, the unit may generate the secondary customer present beep and send the beep to the transceiver. The duration of the customer present beep may be 1 second. When the customer present beep is finished playing, the inbound audio channel to the transceiver is opened.

Each base station may have a distinctly different customer present beep (high/low pitch or/and single/double beep).

Base Transceiver Board

The switches may comply with the following parameters with regard to the base transceiver board. A push-button momentary switch may be provided for reset. If the switch is pressed the unit may read any switches and re-establish connections.

A switch may be provided to select single or dual lane mode. A switch may be provided to select B1/B2 split mode or combine mode. A switch may be provided to select whether Auto uplink override is enabled. A switch may be provided to Start Registration and another to Clear All Registration.

Referring now toFIGS. 36 and 37, there is shown a single lane mobile transceiver operation state diagram, which is similar to the state diagram ofFIGS. 8,9and10for a dual lane mobile transceiver operation. These diagrams ofFIGS. 36 and 37illustrate various operations of mobile transceivers for a single lane system, with the base station operating in a single lane mode of operation.

From a receive only state264, a series of states are entered inFIG. 36in response to pressing the ON/OFF button of a mobile transceiver. Alternatively, from the state264, a series of states are transitioned to inFIG. 37in response to pressing button A1, A2 or B.

InFIG. 37, a transition occurs when pressing B. At state266(FIG. 37), a conference on the B1 channel may take place. When car arrives at the service point and an auto uplink is established, a transition to a state268occurs where transmitting and receiving audio occurs. When the B button is released while in state266, a transition occurs to the receive only state264.

While in the transmit/receive state268, a transition can occur to the receive only state264when a customer leaves the service point or otherwise a time out occurs.

While the present embodiments of the invention is disclosed herein have been particularly shown and described with reference to particular embodiments thereof, it will be understood by those skilled in the art that various changes and forms and details may be made therein without departing from the true spirit and scope of the present invention.