Abstract:
A method and apparatus are disclosed for providing audio-visual communication between registered users. Similar to the traditional walkie-talkie, a user depresses a button to transmit audio information, such as voice, and releases the same button to receive audio information from a transmitting device. Additionally, when communicating to another unit, the transmitting unit can also simultaneously send streaming video or still pictures in conjunction with audio communication. Both the audio and streaming video are transmitted and received in real-time. Still pictures may be stored or transmitted at any time. Each unit comprises a transmitter, antenna, camera, speaker, display screen and battery that are compact enough to be taken anywhere and allow for mobility. To enable security of the device, users must register with each other while within range before any communication can begin. This invention will allow users to communicate with each other for both business and recreational purposes.

Description:
FIELD OF INVENTION 
   The present invention relates to the field of wireless communication. More specifically, the invention relates to the technical field of secure, mobile, audio-visual communication. 
   BACKGROUND OF THE INVENTION 
   In today&#39;s high-tech age of communication, with radiofrequency (“RF”) and WiFi enabled personal digital assistants (“PDAs”), cellular telephones that play media clips while sending pictures, and RF-internet teleconferencing, the selection of a mobile device proves complex for consumers and competition remains high among electronic device manufacturers. Consumers have many different options between products and sometimes must buy more than one device for many distinct situations. Manufacturers and retailers must try to fit as much technology as possible into each device in order to meet this consumer need. 
   Although wirelessly-enabled PDAs, data tablets, laptops and even some handheld wireless game consoles can provide a visual capability for the user, they are inherently and extremely limited in range and are therefore not effectively mobile. In the case of internet enabled PDA&#39;s or mobile teleconferencing terminals, these devices require an expensive hub that severely limits the range between the hub and terminal on both ends, require an expensive routing computer on both ends, as well as, an internet connection with paid service. Similarly, WiFi enabled devices require an expensive hub and also greatly limit the range of connected devices. In all cases, these devices require substantial technical skill for installation and setup and sometimes even for operation. 
   This class of mobile device comes complete with power limitations. They typically run on small batteries and usually communicate under protocols defined in subparts of the general 802.11 specifications. These specifications describe full duplex protocols that require the transmitters to be on at all times. High power levels cannot be maintained without the operating time becoming drastically reduced. These power problem cause further limitations among wireless devices. 
   To date, even cell phones cannot send real-time video that is derived from the camera of the caller. Their use depends upon paid network service and equipped public infrastructure. Hence, cell phones become useless in rural or country areas having poor or nonexistent coverage. They are also useless when the public infrastructure is down for various reasons, possibly including disaster. In addition, the operation of cell phone functionality is often complex. 
   Walkie-talkies hold a special niche in the cluster of communication options and are singularly the most appropriate device in many widely understood situations. They are free and simple to use and are commonplace for both commercial and personal use. However, unlike cellular telephones they lack the ability to send still pictures and streaming video, send secure communication or provide group registration. In many situations where a walkie-talkie is the most appropriate device, users opt to use a less appropriate device such as a cell phone because of its ability to send pictures. The present invention attempts to solve these current problems by providing service that is free, and a device that is capable of transmitting long distance while being very easy to use right out of the box. 
   SUMMARY OF THE INVENTION 
   It is for the foregoing reasons that the purpose of the present invention is to simplify the complexities of today&#39;s communication world by extending the abilities of the walkie-talkie beyond that of today&#39;s expensive, and in the case of cell phones, real-time video-limited devices. Aside from the natural desire of users to want to communicate with each other as if the recipient was virtually present, the disclosed invention gives users numerous benefits not yet achieved for this class of device. These benefits range in diversity from allowing facility maintenance workers to send visual clarification of problems and fixes, to allowing lost children to visually transmit nearby landmarks to frantic parents and receive instructions or directions. As the old idiom goes, a picture is worth a thousand words and thus, by logical extension, video can only be worth more. All of these benefits are achieved securely and simply using the present invention. To achieve these results, the present invention provides the two basic sensory stimuli of sight and sound over the well-accepted use model of the walkie-talkie. Moreover, it is capable of providing these sensations simultaneously and securely. Not only does it provide a more true-to-life effect, but also drastically improves the overall communication of information. 
   The present invention operates on its own proprietary simplex protocol and only transmits when a user is talking; transmitting audio information, visual information or both. This utilizes a low duty cycle model. Hence, longer ranges can be achieved through the use of higher transmit power with drastically reduced average power draw from the unit. 
   The present invention sends real-time video and works in any geographic area on the globe, whether or not in time of disaster. The free and independent nature of this infrastructure has and will keep walkie-talkies a vital means of communication in any time. Their only downfall in the ever-advancing world of communication has been their lack of secure communication and ability to send picture or video. The present invention overcomes the drawbacks of the walkie-talkie by adding a camera, registration capability and its proprietary digital protocol. 
   These and other objectives of the claimed invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  illustrates a front view of a preferred embodiment of the present invention. 
       FIG. 2  illustrates a side view of the left side of the embodiment shown in  FIG. 1 . 
       FIG. 3  illustrates a side view of the right side of the embodiment shown in  FIG. 1 . 
       FIG. 4  illustrates a back view of the preferred embodiment shown in  FIG. 1 . 
       FIG. 5  illustrates a functional block diagram of the internal circuitry contained within the embodiment shown in  FIG. 1 . 
       FIG. 6  illustrates a preferred embodiment of a top level menu of the user interface. 
       FIG. 7  illustrates a preferred embodiment of the best method of selecting RF channels. 
       FIG. 8  illustrates a preferred embodiment of the best method of disabling or enabling video transmission. 
       FIG. 9  illustrates a preferred embodiment of the best method of selecting still pictures. 
       FIG. 10  illustrates a preferred embodiment of the best method of deleting still pictures. 
       FIG. 11  illustrates a preferred embodiment of the best method of displaying still pictures. 
       FIG. 12  illustrates a preferred embodiment of the best method of transmitting still pictures. 
       FIG. 13  illustrates a preferred embodiment of the best method of renaming still pictures. 
       FIG. 14  illustrates a preferred embodiment of the virtual keypad. 
       FIG. 15  illustrates a preferred embodiment of the best method of displaying options after capturing still pictures. 
       FIG. 16  illustrates a preferred embodiment of the best method of displaying options after receiving a still picture. 
       FIG. 17  illustrates a preferred embodiment of the best method of displaying and modifying the names of other devices within range. 
       FIG. 18  illustrates a preferred embodiment of the common list and best method of manually entering names. 
       FIG. 19  illustrates a preferred embodiment of the common list and the best method of automatically entering names. 
       FIG. 20  illustrates a preferred embodiment of the best method of enabling or disabling secure communication. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   In the following description of the various embodiments, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration various embodiments in which the invention may be practiced. It is to be understood that other embodiments may still be utilized and structural and functional modifications may be made without departing from the scope and spirit of the present invention. 
   Referring to  FIG. 1 , a preferred embodiment of device  10  is shown. Device  10  includes a body structure  28  for housing all of the functional electrical elements shown in  FIG. 5  and all associated mechanical and electrical mountings and interconnects. Antenna cap  16  is a mechanical cover of flexible plastic or durable rubber that is chemically bonded to device  10 . Internal antenna  60 , within antenna cap  16 , is a helically wound wire, matched to resonate at the base operating radio carrier frequency of device  10  and is electrically connected to radio frequency switch  58  to allow device  10  to send and receive data, which is either video and voice signals, JPEG format pictures and voice signals, or just voice signals as radio frequency signals. 
   As best shown in  FIGS. 1-4 , are a combination of external features located on body structure  28 . LCD screen  16  is a protective transparent layer covering the active display area of LCD module  56 . LCD module  56  contains LCD control circuitry along with sufficient memory to store a full-screen image, the LCD glass and power control. LCD module  56  is an off-the-shelf single unit bought from a single vendor. 
   User button cap  20  is used to call up and extinguish an on-screen menu displayed on LCD screen  16  and is mechanically connected such that it actuates a singularly specific one of the eight user buttons  50 . A four-way axis, up, down, right and left-actuated user button cap  24  is used for manipulating the on-screen menu-selection cursor and is mechanically connected such that it individually actuates four of the eight user buttons  50  one at a time. User button cap  26  is used for on-screen menu selection and is also used to power device  10  on and off, by pushing it briefly to transition device  10  from “off” mode to “on” mode, and by depressing it for more than three seconds to transition device  10  from “on” mode to “off” mode. User button cap  26  is mechanically connected such that it actuates a singularly specific one of the eight user buttons  50 . 
   As best shown in  FIG. 2 , user button cap  30  is used to select between transmit and receive functions of device  10 . When user button cap  30  is actuated, transmission of data is enabled and active. Data is transmitted through antenna  60 . When user button cap  30  is not actuated device  10  is in “receive” mode and will receive data from another device  10  that is registered to it. User button cap  30  is mechanically connected such that it actuates a singularly specific one of the eight user buttons  50 . 
   As best shown in  FIG. 3 , user button cap  32  is used to take snap shot pictures of visual information that is within the visual field of CMOS image sensor  68 , send that information to digital signal processor (“DSP”)  40  for JPEG compression and store that compressed JPEG format information as a picture within the flash memory  41  of DSP  40 . The JPEG format picture stored in flash memory  41  can be viewed on LCD screen  16  or transmitted to another device  10 . Control of picture display, transmit and management of JPEG format pictures is achieved with on-screen menu selections displayed by LCD module  56  which is controlled and manipulated by user button caps  20 ,  24  and  26 . JPEG format pictures can also be received from another device  10  and stored in flash memory  41  and manipulated in the same manner as a JPEG format picture that was generated locally on device  10 . User button caps  20 ,  24  and  26  also are used to control and manipulate the on-screen menu to disable and re-enable video. Upon power up, the default condition will always be video transmission enabled so the on-screen menu will have to be accessed to disable it. When the on-screen menu is not displayed, pressing user button cap  24  up or down will respectively increase the audio volume generated by speaker  46  up or down. When user button cap  30  is actuated, transmission of data is enabled and active through antenna  60 . When user button cap  30  is not actuated, device  10  is in “receive” mode and will receive any data transmitted to it. User button cap  30  is mechanically connected such that it actuates a singularly specific one of the eight user buttons  50 . 
   Again referring to  FIGS. 1-4 , perforated grill plate  22  covers and provides protection for speaker  46 . Speaker  46  emits the audio portion of data received by device  10 . In “receive” mode, data is received through antenna  60 . In “receive” mode, radio frequency switch  58  connects the radio frequency data to the receive port on the radio frequency transceiver chip  66 . The radio frequency transceiver chip  66  then down converts the data to base band and demodulates it in to a digital data stream. This digital data stream is input to DSP  40  and checked to make sure it is a stream from a registered device  10 . If the stream is not recognized from a registered user, it is ignored. If a stream is recognized as from a registered device  10 , then the data is decompressed by DSP  40 . The compression used for both transmit and receive adheres to the ISO H.264 standard. The H.264 data stream is then parsed by data type. Audio data type is converted from digital format to an analog signal by an integrated digital to analog converter on DSP  40 . This analog signal is then filtered and amplified by audio driver circuit  48  and played in real-time on speaker  46 . Volume control of this amplified signal is achieved by reducing the dynamic range of the digital to analog converter on DSP  40 . Video data type is displayed real-time on LCD screen  16 . When the received signal is terminated, the last received frame of video will persist on LCD screen  16  until another stream is received or until device  10  is powered down. Decompressed data type JPEG pictures are displayed immediately on LCD screen  16  and display of any received video data type is suspended until user button cap  32  is pressed or the image is stored in flash memory  41  located in DSP  40 . Storage of a JPEG picture in DSP  40  flash memory  41  is done through the on-screen menu. Display of data type video is resumed once the image is stored. 
   Perforated grill plate  22  covers and provides protection for microphone  42  as well as speaker  46 . When button cap  30  is actuated no further reception of any present data stream is allowed. Single chip transceiver  66  switches into “transmit” mode, radio frequency switch  58  disconnects antenna  60  from the receive port on single chip transceiver  66  and connects antenna  60  to the output of radio frequency power amplifier  62 . Audible signals in the ambient environment detectable by microphone  42  are filtered and amplified by microphone filter and preamp  44 . This analog signal is input to an analog to digital converter on DSP  40  and compressed in ISO H.264 format. If the default transmit video function is enabled, visual information within the visual field of CMOS image sensor  68  is also compressed in H.264 format and added to the outgoing data stream. If a JPEG picture has been sent, it is specially tagged and added to the data stream. This tag will inform the receiving device  10  to treat that frame as a picture and not a video frame. The completed data stream is then input to the single chip transceiver  66  where it is modulated and up converted to the carrier frequency of device  10 . This signal is then filtered by radio frequency harmonics filter  64  and input into radio frequency power amplifier  62 . The amplified radio signal from radio frequency amplifier  62  is passed through radio frequency switch  58  and radiated out of antenna  60 . 
   Visual information detected by CMOS image sensor  68  is optically focused onto the active area of CMOS image sensor  68  by lens assembly  12 . Lens assembly  12  is attached to body structure  14  through a threaded hole that allows for focus adjustment during manufacturing and allows the user to make adjustments if optical alignment is lost over time due to mechanical stresses. Body structure  14  is independent from body structure  28  and can swivel up to 210 degrees around an axis parallel to screen  16 . 
   As shown best in  FIG. 4 , power supply  54  for device  10  is a bank of four AA Alkaline batteries. This bank of batteries is retained by battery door  34 . Battery door  34  is retained by a battery door release  36  and a retained series of clips  38 . The power supply  54  is separated into regulator array  52  that isolates the system power from the radio frequency device power and the LCD bias power. This is done to reduce noise cross over and to generate an LCD module  56  bias voltage that is negative with respect to the other power forms. 
   The data stream output from antenna  60  is formed by DSP  40  into sequential frames comprised of numerous packets. Each frame contains tags to insure secure communication is conducted between only device  10  units that are registered to a common list that is stored in flash memory  41  in DSP  40 . Registration is done by device  10  units sharing entries in the common list. To communicate within any group of device  10  units, each common list maintained in a device  10  unit must contain the serial number of each of the other device  10  units that will communicate together. Each device  10  that is manufactured contains a serial number that is unique to each device  10  and can be viewed using the on-screen menu and will be printed on the back of the unit. This unique serial number is stored in flash memory  41  in DSP  40 . In addition there is an optional name tag that is comprised of an ASCII text string that is input by a user into their device  10  and stored in flash memory  41  in DSP  40 . The name tag text string is constructed using the on-screen menu displayed on LCD screen  16  and typically will be the name a user whishes to use to identify them self when their transmissions are received by other device  10  units. The serial numbers are added to a common list either manually by using the on-screen menu or by using a low-power automatic broadcast registration mode. In order to delete a common list entry removal must be done manually using the on-screen menu. For automatic broadcast registration, all units must be put in registration mode using the on-screen menu. Once in registration mode, the transmit power of the all device  10  units in that mode is drastically reduced to a limited range. All units in that mode monitor for transmissions of special registration frames containing the serial number tag, the name tag and a special command encoded into the frame packets. Each user in range then takes turns pressing their user button cap  30  which causes transmission of a registration frame. All units within range then place the serial number tag and name tag of the transmitting unit into the common list. As the common list is built, the entries are shown in text form on LCD screen  16 . 
   Secure mode is optional and may be disabled by using the on-screen menu. When disabled, the common list is ignored and each frame&#39;s name tag is transmitted and received as a blank and the serial number is transmitted and received as a zero. In this way, device  10  units can communicate with all other device  10  units that have the security function disabled but cannot eavesdrop on other device  10  units that have their security mode enabled. 
   Device  10  operates on a number of different radio frequency channels. Channels are radio carrier frequencies that are spaced within the entire operating band and are out of the operating bandwidth such that transmission signals from a device  10  operating in one channel is not received by a device  10  operating in another. Device  10  operating channels are set by using the on-screen menu. 
   The software for device  10  can be stored in DSP  40  flash memory  41  along with JPEG pictures, tags and other configuration settings. This software can be loaded at the time of manufacture. 
   As best shown in  FIG. 5 , is a functional block diagram of the internal circuitry contained within the embodiment shown in  FIG. 1 . DSP  40  receives input from antenna  60  when RF switch  58  allows. DSP  40  transmits data to antenna  60 , in one embodiment, through transceiver  66 , filter  64 , and power amplifier  62 . The received visual transmission interfaces through buss interface on DSP  40  and is displayed by LCD module  56 , which consists of LCD screen  16 , LCD controller and LCD memory. Additionally, CMOS image sensor  68  can collect visual transmission and send it directly to LCD module  56 , without interacting with DSP  40 . Input audio transmission is recorded from microphone  42  and in one embodiment pass through filter and preamp  44  before being converted through an analogue digital converter in DSP  40 . Oppositely, audio transmission output to speaker  46  passes through an analogue-digital converter on DSP  40 . User buttons  50  interact with DSP  40  for general purpose input/output (“GPIO”) functionality. Power supply  54 , which can be disposable or rechargeable batteries, provides power to device  10  through battery array  52 , which keeps the device power separate from the system, RF transceiver  66  and LCD module  56 . 
   As best shown in  FIG. 6 , is top level menu  80  that is brought up after device  10  is powered. Pressing button cap  20  upon start-up will also bring up this top level menu  80  if it is not presently shown. Top menu  80  allows the user to choose from a select list of menu items  91 - 94  which represent various functions and modes for device  10 . Outermost frame  85  represents the outer edge where LCD screen  16  meets the faceplate of device  10 . Graphics and text within frame  85  are displayed as shown in the following figures. 
   One of menu items  91 - 94  will be selected by momentarily pressing button cap  26  or actuating button cap  24  right. Either of these actions will be referred to as selecting an item. Items to be selected are first highlighted by being displayed in an inverse color scheme with respect to other menu items. Highlighted menu item  90  is first highlighted before it can be selected. In addition, dark arrow  82  is shown to the left of highlighted menu item  90 . Arrow  82  will always point to highlighted menu item  90 . Actuating button cap  24  up or down will highlight the next menu item that is respectively up or down from the highlighted selection before the actuation is performed. Actuating button cap  24  up when highlighted menu item  90  is at the top-most item of any menu will cause no further action. Similarly, actuating button cap  24  down when highlighted menu item  90  is at the bottom-most menu item will also cause no further action. If a list of menu items does not fit on screen  16 , scrolling will be possible. Factory-assigned serial number  100  is always displayed at the bottom center of top menu  80 . 
   In one embodiment of the present invention, menu items  91 - 94  comprise channel item  91 , video item  92 , secure item  93 , and pictures item  94 . Items  91 - 94  are only displayed in top menu  80 . Some items  91 - 94  will have deeper layers of menus associated with them that are indicated by the presence of submenu indicator arrows  84 . Submenu indicator arrows  84  are shown on the right side of each menu item  91 - 94  when applicable. If no submenu is available, arrow  84  will not be present. Pressing button cap  20  will always return display screen  16  to the menu or submenu that has previously been shown. Selecting a menu item will advance screen  16  to the next possible submenu. When there are no further submenus stored in flash memory  41 , pressing button cap  26  or actuating button cap  24  right will cause no further action. Similar to pressing button cap  20 , actuating button cap  24  left will cause display screen  16  to return to the previous submenu or top menu  80 . Either of these actions will be referred to as deselecting an item. When top menu  80  is displayed, deselecting an item  91 - 94  will cause no further action. 
   Now referring to  FIG. 7 , top menu  80  is shown along with channel item  91  and the best method of selecting available RF channels. When channel item  91  is highlighted in top menu  80 , actuating button cap  24  right will advance through available channels. Pushing button cap  24  left will regress to previous channels. When the desired available channel is highlighted, pressing button cap  26  will select that channel for use. Other top level menu items  92 - 94  will still be displayed as different channels are selected. 
   Now referring to  FIG. 8 , top level menu  80  is shown along with video item  92  and the best method of enabling or disabling video transmission. When video item  92  is highlighted in top menu  80 , actuating button cap  24  right will disable video transmission. Actuating button cap  24  left will enable video transmission. Other top level menu items  91 ,  93  and  94  will still be displayed as video is enabled or disabled. 
   Now referring to  FIG. 9 , top level menu  80  is shown along with pictures item  94 , shown as a black box on the left of  FIG. 9 , and the best method of selecting available pictures. When picture item  94  is highlighted in top menu  80 , actuating button cap  24  right will advance to a list of picture titles  75 , shown on the right of  FIG. 9 , of all available pictures stored in memory  41 . If no pictures are stored in memory  41 , the text “NO PICTURES” will be displayed at the top of LCD screen  16 . When a picture from list  75  has been selected, it may be deleted, displayed, renamed or transmitted to other devices  10 , as shown in  FIGS. 10-13 . These possible actions are selected by scrolling up or down, using button cap  24 , in the same manner that menu items  91 - 94  are selected. 
   Now referring to  FIG. 10 , picture list  75  is shown along with delete item  95 , shown as a black box in the middle of  FIG. 10 , and the best method of deleting pictures. When delete item  95  is highlighted, actuating button cap  24  right will cause a confirmation box to appear, as shown on the right of  FIG. 10 . Selecting “YES” will delete the originally highlighted picture from memory  41  and revert screen  16  to picture list  75 . Selecting “NO” will have no effect except to revert screen  16  to picture list  75 . 
   Now referring to  FIG. 11 , picture list  75  is shown along with display item  96 , shown as a black box in the middle of  FIG. 11 , and the best method of displaying pictures. When display item  96  is highlighted, actuating button cap  24  right will cause the selected picture to appear, as shown on the right of  FIG. 11 . Pressing any button while a picture is being displayed will revert screen  16  to picture list  75 . 
   Now referring to  FIG. 12 , picture list  75  is shown along with send item  97 , shown as a black box on the right of  FIG. 12 , and the best method of transmitting pictures to another device  10 . When send item  97  is highlighted, actuating button cap  24  right or button cap  26  will transmit the originally highlighted picture to other devices  10  that are within range and listed in the universal common list  120 . Pictures that are transmitted to another device  10  retain the name that was assigned in the transmitting device  10 . 
   Now referring to  FIG. 13 , picture list  75  is shown along with rename item  98 , shown as a black box in the middle of  FIG. 13 , and the best method of renaming pictures. Pictures that have not been manually named are assigned a name by device  10  and stored in flash memory  41  with the title as “picture” followed by a numeral. The numeral indicates the order in time in which the particular picture had been stored in flash memory  41 . Pictures with names assigned by device  10  are automatically renumbered if a picture is deleted so that the number sequence is always contiguous starting from number one. When rename item  98  is highlighted, actuating button cap  24  right will cause virtual keypad  110  to be displayed, as shown on the right of  FIG. 13 . Pictures are renamed using keypad  110 . After a new name is assigned, keypad  110  can be exited by pressing a virtual exit button located on the keypad or by actuating button cap  20 , either of which will return screen  16  to picture list  75 . 
   As best shown in  FIG. 14  is virtual keypad  110  that can be called by some menu items  91 - 99 . Keypad  110  is divided into two distinct fields; input field  112  and text field  114 . One field will always be highlighted when keypad  110  is called and displayed. Boxes containing letters, numbers and symbols comprising punctuation marks and editing commands, such as erase, backspace, and enter, in the input field are highlighted one at a time. The highlighted cursor is maneuvered over the grid of boxes in the up, down, right, and left directions by respectively actuating button cap  24  in the same direction. Text field  114  shows the name of the menu item that called keypad  110  when it is first shown. Text field  114  can be modified by highlighting boxes in input field  112 , in the manner described above, and selecting an enter button on keypad  110  or actuating button cap  26 . Again, keypad  110  can be exited by highlighting “EXIT” or actuating button cap  20 . 
   In one embodiment of the present invention, while device  10  is not displaying any menu, actuating button cap  32  will cause a still picture to be captured from the visual field of CMOS image sensor  68 . The picture will be stored in DSP flash memory  41  and will override any video reception and be persistently displayed on screen  16 . Now referring to  FIG. 15 , shown is superimposed menu  69 . The highlights for menu  69  are selected using button cap  24  in the same manner as other menu items  91 - 99 . Storing or discarding the captured picture to DSP  40  flash memory  41  is accomplished by highlighting “SAVE” or “DISCARD”. After saving or discarding the captured picture, screen  16  will revert to display the menu that was displayed immediately before menu  69 . The captured picture can also be immediately sent to other devices  10  in range that share the same common list using send item  97 . If the allocated flash memory  41  is full, older pictures can be overwritten. 
   In one embodiment of the present invention, while device  10  is not displaying any menu, it may receive a picture from another device  10 . The picture will be stored in DSP  40  flash memory  41  and override any video reception and be persistently displayed on screen  16 . Now referring to  FIG. 16 , shown is superimposed menu item  67 . The highlights for menu  67  are selected using button cap  24  in the same manner as other menu items  91 - 99 . Storing or discarding the received picture to DSP  40  flash memory  41  is accomplished by highlighting “SAVE” or “DISCARD”. After saving or discarding the captured picture, screen  16  will revert to display the menu that was displayed immediately before menu  67 . If the allocated memory  41  is full, older pictures can be overwritten. 
   Now referring to  FIG. 17 , top level menu  80  is shown along with the name item  95  and the best method of displaying and modifying the names of other devices  10  within range. When the name menu item is highlighted, actuating button cap  24  right or button cap  26  will display keypad  110 . Text field  114  contains any previously assigned name of the device  10  or if none has been assigned, the serial number of the device  10 . A new name can be assigned using input field  112  on keypad  110 . 
   As best shown in  FIG. 18  is top level menu  80  along with common list  120  and the best method of displaying available names of devices and manually entering names. When “NAME” is highlighted on top level menu  80 , actuating button cap  24  right or button cap  26  will display the common list  120 . The first entry on common list  120  is always “ADD NEW,” shown as a black box in the middle of  FIG. 19 . When “ADD NEW” is highlighted, actuating button cap  24  right or button cap  26  displays a second menu, shown on the right of  FIG. 18  and comprises manual item  122  and automatic item  124 . When manual item  122  is highlighted, actuating button cap  24  right or button cap  26  will call and display keypad  110 . A new name can be entered manually using keypad  110 . Names can also be deleted from common list  120  in a similar manner as pictures are deleted. If no devices are within range and no names have been previously entered, then the text “NO ENTRIES” will be displayed below “ADD NEW”. Available names in common list  120  are arranged by serial number  100 . 
   As best shown in  FIG. 19  is common list  120  along with automatic item  124  and the best method for displaying available names of devices and automatically entering names. When automatic item  124  is highlighted, actuating button cap  24  right or button cap  26  will display instruction screen  128  containing instructions to push transmit button  30  to register with other devices  10 . Other devices in registration mode will receive the name and serial number  100  of the transmitting device  10  and automatically append common list  120 . Registration of devices  10  with each other can not occur simultaneously. While transmitting, any reception of registration data will be disabled. When registration information is received by device  10  in automatic registration mode, a 1 KHz. tone is transmitted over speaker  46  for a duration of  500  milliseconds after the name and serial number  100  of transmitting device  10  has been added to common list  120 . 
   Now referring to  FIG. 20 , top level menu  80  is shown along with secure item  93 , shown as a black box, and the best method of enabling or disabling secure communication between registered devices  10 . When secure item  93  is highlighted in top menu  80 , pushing button cap  24  right will disable secure communication. Pushing button cap  24  left will enable secure communication. Other exemplary top level menu items  91  and  92  will still be displayed as security is enabled or disabled. 
   The present invention includes any novel feature or combination of features disclosed herein either explicitly or any generalization thereof. While the invention has been described with respect to specific examples including presently preferred modes of carrying out the invention, those skilled in the art will appreciate that there are numerous variations and permutations of the above described apparatus and techniques. Thus, the spirit and scope of the invention should be construed broadly as set forth in the appended claims.