In many of today's leading companies, employees carry multiple devices for data and voice communications, including data terminals, pagers, cell phones or walkie-talkies. The walkie-talkie is the most prevalent device and is used for real-time associate communications such as addressing questions, problems or emergencies in a responsive manner. In addition, management-level associates often listen in on these conversations to assess day-to-day activities and be more responsive to situations that may benefit from management intervention. Instant communications by walkie-talkie enables more effective problem solving and decision making.

However, conventional walkie-talkie devices vary widely in price and features. Some are inexpensive with limited capabilities; others are feature rich and durable but expensive with additional fees to license the radio spectrum. For associates who require other devices to perform daily tasks, a walkie-talkie is a cumbersome item to carry throughout the day, and one that offers little value after the conversations are over.

Voice Communicator from Symbol Technologies meets the need for real-time, interactive voice communications by employees. Symbol is a leader in enterprise mobility solutions that enable anywhere, anytime data and voice communication and a pioneer in wireless local area network (WLAN)-based voice-over-IP (VoIP). The Voice Communicator application utilizes a radio frequency (RF) infrastructure combined with mobile computers and the award-winning Spectrum24® 802.11b wireless LAN from Symbol.

Voice Communicator from Symbol Technologies is a unique, converged solution that merges the superior data capture and management features of Symbol terminals and powerful wireless LAN communications with the same voice capabilities as traditional walkie-talkies. The result is a single device on a single network that is used for multiple purposes, enabling today's companies to do more for less.

Leveraging an installed Spectrum24 802.11b wireless LAN infrastructure as a medium for voice applications is advantageous, because many mobile computers from Symbol already host these applications. Voice Communicator is one such audio-enabled application that runs on voice-enabled Symbol devices running the Microsoft® Windows® Pocket PC operating system. The rugged PDT 8146 handheld mobile computer, powered by the Intel® XScale™ processor, is the first handheld that features the Voice Communicator application, which delivers:

• One-to-many audio communications (like a walkie-talkie) via a push-to-talk (PTT) button.

Peer-to-peer, full duplex audio communications between voice-enabled devices.

With the PDT 8146 and Voice Communicator, employees communicate in real time to provide each other with valuable information or feedback from wherever they are in the facility. This dynamic application conveniently utilizes the media and bandwidth that is already available with a Spectrum24 802.11b wireless LAN infrastructure.

Figure 1: Sample Screen Image of Voice Communicator

Voice Communicator functionality builds from the features of a traditional walkie-talkie. In addition to supporting a one-to-many, push-to-talk capability (PTT), Voice Communicator also supports the partitioning of devices and users into one or more of up to 256 channels. Unlike VHF walkie-talkies which are limited to physical frequency channels, Voice Communicator extends the concept of a channel for functional grouping purposes independent of physical transmission frequencies. Any one user is configured to belong to any number of the 255 available channel assignments. As a result, initiating calls to functional groups of associates (e.g., facilities, security) is easily accomplished by selecting the designated channel. This operation involves only those associates who are assigned to that selected channel.

Figure 2: One-to-Many, Half-Duplex Mode

In addition to the half duplex PTT mode, Voice Communicator also supports a full duplex peer-to-peer (P2P) mode. During the course of a half duplex PTT conversation among channel participants, anyone receiving the last broadcast message can initiate a private call to the last speaker at the touch of a button. If accepted, the call connects and those two associates are now outside of the PTT broadcast stream and are holding their own private full duplex conversation (see Figure 3). After hanging up, both associates return to monitoring their channel traffic.

Figure 3: Peer-to-Peer Full Duplex Mode

The advantages of the Voice Communicator go beyond the two basic modes of communication. Yes, it's a powerful productivity tool that offers a wide variety of methods and options for employee communications. But equally important, it empowers companies to improve employee productivity, cost-effectively realize the maximum return on investment (ROI) and achieve strategic IT and business goals.

3.1 Simplification

Combining the power and usefulness of the rugged PDT 8146 mobile computer from Symbol with the benefits of voice-over-IP walkie-talkie and P2P helps companies realize a number of important IT management goals:

• Lower total cost of ownership (TCO)
  802.11b operates on the ISM (Industrial, Scientific and Medical) band, which is unregulated and available free unlike some walkie-talkies that require licensed spectrum (paying for the right to use the airwaves)
  Buy fewer devices – configure, deploy, maintain, repair and replace a smaller number of handhelds

• Fewer batteries to manage
  Reduces fatigue for associates who carry communications and productivity devices for a full shift

3.2 Benefits

The PDT 8146 with Voice Communicator offers a variety of productivity and cost-saving features.

• Manageability:
  Acts as another IP device on the network and is capable of routing communications within a LAN subnet

• Durability:
  PDT 8146 is more rugged when compared to PTT handsets such as Nextel and many off-the-shelf walkie-talkies

• Security:
  Operates under the same secure wireless implementation as your data network; today's cell phones and walkie-talkies cannot offer this

• Scalable:
  Adds more logical groupings and users beyond the 12 standard VHF channels with up to 256 channels

• Future proof:
  Follows IEEE standards for interoperability and allows new feature upgrades through software

• Integrated DSP:
  Enables concurrent data and voice applications with no loss in terminal performance, functionality or voice quality, because the DSP frees up the central processor to handle data-intensive applications (i.e., inventory access, transaction processing)
  Delivers G.729a compression support for more voice traffic per access point for more efficient use of wireless LAN bandwidth
  Provides acoustic echo cancellation to provide a full duplex speakerphone capability

• Quality of Service (QoS):
  This is maintained through voice prioritization and pre-emptive roaming logic from Symbol; minimizes risk of overloaded access points, because voice packets are prioritized over data packets to reduce latency while pre-emptive roaming allows mobile clients to load balance across the wireless LAN infrastructure

3.3 Features and Uses

Voice Communicator offers many additional capabilities to the PDT 8146. Some examples include:

• Replay:
  Double check important message information such as a phone number, SKU number or directions by listening to a recording of the last received broadcast

• Emergency Channel:
  Treat as ‘barge' feature breaks through existing PTT discussions to notify associates of hazardous warnings such as fire, chemical spill, medical emergency or security alert

• Power-save Mode:
  Used when the mobile computer is not scanning or running other applications but still allows employees to receive voice communications; for example, this mode enables a manager to save battery life while monitoring chatter by turning off the PDT 8146 screen while he or she is roaming the floor

• Call Back:
  Used to establish a full duplex private conversation

• Directed Calling:
  Emulates a Nextel connection and provides direct 1-to-1 half duplex speech by dedicating an otherwise unused channel to just two associates

• Channel Naming:
  Assigns specific names to channels so that the purpose of each channel is clear (e.g., sporting goods), and a directory allows the user to pick channels and view current channel configuration

• Multi-channel Monitoring:
  Allows an associate to select several channels and listen for messages on those selected channels simultaneously; this feature is easy to enable or disable

• Channel Configuration – Mandatory Channels:
  Sets aside a channel as mandatory for all associates and/or managers for streamlined global announcements of a non-emergency nature; channels are easy to define by groups, such as all retail sales associates, security personnel or even by location and floor

• Caller ID:
  Identifies the source of incoming messages, both walkie-talkie and private peer-to-peer calls

• Collision Resolution:
  Ensures that all listeners of walkie-talkie messages hear the same message if multiple users simultaneously press PTT

The PDT 8146 is an excellent productivity tool that works in many work environments. The context for the value of a converged voice and data solution is demonstrated using two examples: warehouse and retail.

4.1 Warehouse

Daily, warehouse personnel are busy performing stocking in addition to pick and place operations. Operators use mobile computers to check task lists that were downloaded after the initial logon to their terminal. And workers also busily scan pallets to record the type and quantity of items placed and then scans location tags to record where the inventory is stored.

However, sometimes the count is wrong, the stock item is incorrect or other exception handling is required. Now, the forklift operator uses the Directed Calling feature on his or her PDT 8146 with Voice Communicator to query the floor supervisor.

The supervisor decides to move the current stock to make room for the new shipment. Acting as a dispatcher, the supervisor changes channels to "Forklift" and uses PTT mode to broadcast a message to all forklift operators to find the closest available operator to move the current stock.

4.2 Retail

At a ladies' apparel store, associates spend most of their time on the sales floor assisting customers to increase store revenue. A customer approaches a sales associate and asks: "How much is the black turtleneck sweater? The tag is ripped." The sales associate scans the bar code on the price tag and uses the PDT 8146 to access a price verification application. The information is given to the customer rapidly: "This sweater is on sale today for $39.95."

The customer also wants to know if the store has a size 6 in stock. For an inventory check, the sales associate uses their PDT 8146 with Voice Communicator set to the "Store Room" channel. The associate in the store room asks for the SKU number to confirm, which the sales associate reads from the scanning application screen.

Finally, the sales associate notices the long line at the register and offers to do line busting: "Would you like me to take care of that purchase for you right here? I just need your Customer Loyalty card." By swiping the card in the magnetic stripe reader attached to the PDT 8146, the transaction is rapidly completed using customer account information maintained in the company database.

Symbol Technologies delivers enterprise mobility solutions that enable anytime, anywhere data and voice communication to help companies' increase productivity, reduce costs and realize competitive advantage. Voice on terminals (VOT) is an important Symbol initiative that enhances its robust enterprise mobility product and wireless technology portfolio.

The PDT 8146 terminal with Voice Communicator is unique and provides more functionality than a traditional mobile computer, more capabilities than a traditional walkie-talkie and more combined value than any similar product. And it's fully software upgradeable to provide for even more voice capabilities in the future.

Symbol developed the Voice Communicator application to enhance enterprise mobility tools, such as the PDT 8146, with instant group communications using VoIP over an existing 802.11b wireless LAN. The result is a single handheld on a single network that is used by employees for a variety of tasks.

The PDT 8146 with Voice Communicator enables today's companies to do more for less.

802.11b: The family of specifications created by the Institute of Electrical and Electronics Engineers Inc. (IEEE) for wireless Ethernet LANs in the 2.4 gigahertz bandwidth space.

Full Duplex: A mode of audio or data communication that works in both directions simultaneously without losing contact.

G.729a: The International Telecommunications Union's (ITU) standard voice algorithm for the coding and decoding of speech at 8 kilobits per second.

Half Duplex: A mode of audio or data communication that works in both directions but not at the same time.

IP: Internet protocol.

Peer-to-Peer (P2P): One-to-one communications between two parties; performed only via the voice end points and does not require any additional entity to negotiate communications.

Push-to-Talk (PTT): A type of communication whereby audio transmission is gated by the user's pressing a designated key (or button) on the voice end point before and during speaking.

QoS (Quality of Service): Refers to a subjective level of acceptable voice quality under all conditions such as congested networks or concurrent voice and data on the wireless LAN.

RF: Radio frequency.

Subnet: A portion of a network that shares a network address with other portions of the network.

VHF: Very high frequency portion of the electromagnetic spectrum with frequencies between 30MHz and 300MHz; operating band for radio and television.

VoIP (Voice over Internet protocol): Digitized and packetized voice, the technology used to transmit voice conversations over a data network using the Internet protocol.

WLAN: Wireless Local Area Network

Symbol Technologies, Inc. (NYSE:SBL) delivers enterprise mobility solutions that enable anywhere, anytime data and voice communication designed to increase productivity, reduce costs and realize competitive advantage. Symbol systems and services integrate rugged mobile computing, advanced data capture and wireless networking for the world's leading retailers, transportation and logistics companies and manufacturers as well as government agencies and providers of healthcare, hospitality and security.