US 5,726,984 · Granted 1998-03-10
The 1998 Patent That Let Wireless Devices Talk Like Phone Calls
Imagine a delivery driver with a handheld device that could make real voice calls over a wireless network instead of just sending text. This patent describes a clever system that mixes wireless networks, internet, and phone lines so your voice can travel smoothly no matter which path it takes — and you don't have to think about it.
The plain-English version
What it protects
The claim covers a hierarchical communication system that blends wired and wireless networks to transmit voice as both real-time streams and as digital packets. What's protected here is the method of converting voice between analog phone format and digital packet format, routing it through a mix of wireless spanning trees, wide area networks, and telephone switches, and presenting the whole experience as a seamless call to the user — whether they're using a mobile device, a computer, or a traditional phone.
Why it matters
In the mid-1990s, wireless devices were mostly for data—text messages, inventory tracking, basic signals. This patent imagined a world where portable terminals and computers could make actual voice calls over mixed networks as naturally as picking up a telephone. It represented an early vision of converged communications that would eventually become central to modern mobile networks, where WiFi calls, internet calling, and cellular voice all coexist on the same device.
Real-world use
A delivery driver using a wireless handheld device to call the warehouse in real time over the company's private radio network, which seamlessly bridges to the main office phone system — all without the driver knowing or caring which technology is carrying the call.
Original USPTO abstract
A packet-based, hierarchical communication system, arranged in a spanning tree configuration, is described in which wired and wireless communication networks exhibiting substantially different characteristics are employed in an overall scheme to link portable or mobile computing devices. The network accommodates real time voice transmission both through dedicated, scheduled bandwidth and through a packet-based routing within the confines and constraints of a data network. Conversion and call processing circuitry is also disclosed which enables access devices and personal computers to adapt voice information between analog voice stream and digital voice packet formats as proves necessary. Routing pathways include wireless spanning tree networks, wide area networks, telephone switching networks, internet, etc., in a manner virtually transparent to the user. A voice session and associate call setup simulates that of conventional telephone switching network, providing well-understood functionality common to any mobile, remote or stationary terminal, phone, computer, etc.
Patent details
- Publication number
- US 5,726,984
- Filing date
- 1995-10-05
- Grant date
- 1998-03-10
- Assignee
- Norand Corporation
- Inventor(s)
- KUBLER; JOSEPH J., MORRIS; MICHAEL D.
- CPC class
- G07F7/02
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