Multipath tolerant cellular communication system and method

• US 5,815,813 A
• Filed: 11/24/1995
• Issued: 09/29/1998
• Est. Priority Date: 11/24/1995
• Status: Expired due to Term

• Current Assignee: Apple Inc.
• Original Assignee: Northern Telecom Limited (Nortel Networks Corporation)
• Inventors: Faruque, Saleh
• Primary Examiner(s): Chin, Tommy P.
• Assistant Examiner(s): RAO, ANAND SHASHIKANT
• Application Number:
  US08/562,391
• Time in Patent Office: 1,040 Days
• Field of Search: 455/33.1, 455/33.2, 455/33.4, 455/33.3, 455/56.1, 455/56.2, 455/62, 455/63, 455/34.2, 455/34.1, 379/54, 379/58, 379/66
• US Class Current: 455/446
• CPC Class Codes: H04W 16/00 Network planning, e.g. coverage or traffic planning tools; Network deployment, e.g. resource partitioning or cells structures

Abstract

A method for deploying a PCS system wherein radio transceivers are deployed at spacings which correspond to a diameter of a first Fresnel zone and set output powers of the transceivers to define cells which correspond to the first Fresnel zone of the transceivers. A PCS system having radio transceivers deployed at spacings corresponding to a diameter of a first Fresnel zone and operating at output powers which define cells corresponding to the first Fresnel zones of the transceivers. A handoff area surrounds the first Fresnel zone breakpoint.

Claims

1. A cellular communication system, comprising:

a plurality of transceivers for transmitting and receiving predetermined RF frequencies to and from mobile units, each of said plurality of transceivers having an antenna for radiating and collecting the respective RF frequencies and having output power defining a cell corresponding substantially to a first Fresnel zone of the RF frequencies;

each of said transceiver antennae being spaced from one another a distance substantially corresponding to the diameter of the first Fresnel zone;

each of said cells having a boundary which forms an annulus of attenuated radiated power and the annulus surrounding each cell overlaps adjacent cells; and

each boundary of said cell substantially coincides with the first Fresnel zone breakpoint determined by the equation;

d₀ =d=4h₁ h₂ /λ

where d₀ is the first Fresnel zone breakpoint, d is the distance between the transceiver antenna and the mobile antenna, h₁ is the height of the transmit antenna, h₂ is the height of the receive antenna, and λ

is the wavelength of the RF frequencies.

2. A method of configuring a communication system having a plurality of transceivers for transmitting and receiving predetermined RF frequencies to and from mobile units, each transceiver having an antenna for radiating and collecting the respective RF frequencies, said method, comprising:

providing each of said plurality of transceivers with output power defining a cell substantially corresponding to a first Fresnel zone of the RF frequency; and

deploying said transceiver antennae at a distance from one another no greater than the diameter of the first Fresnel zone, said distance defined by;

d₀ =d=4h₁ h₂ /λ

, where d₀ is the first Fresnel zone breakpoint, d is the distance between the transceiver antenna and the mobile antenna at the periphery of the cell, h₁ is the height of the transmit antenna, h₂ is the height of the receive antenna, and λ

is the wavelength of the RF frequency.

3. A cellular communication system, comprising:

a plurality of transceivers for transmitting and receiving predetermined RF frequencies to and from mobile units, each of said plurality of transceivers having an antenna for radiating and collecting the respective RF frequencies and having output power that defines a cell corresponding substantially to a first Fresnel zone of the RF frequencies, said transceiver antennae being spaced from one another a distance substantially corresponding to a diameter of the first Fresnel zone;

each of said cells having a boundary substantially coinciding with a breakpoint in the first Fresnel zone to form an annulus of attenuated radiated power surrounding each cell and overlapping an adjacent cell, the plurality of transceiver antennae being located within a building enclosure having different propagation media,

wherein the first Fresnel zone breakpoint is determined by the equation;

d₀ =d=4(H-h₂)h₂ /λ

wherein d₀ is the first Fresnel zone breakpoint, d is the distance between the transceiver antenna and a mobile antenna, h₂ is the height of the mobile antenna, H is the ceiling height of the building enclosure and is equal to the sum of h₁ and h₂, h₁ is the height of a transmit antenna, and λ

is the wavelength of the RF frequency.

4. A method of configuring a communication system having a plurality of transceivers for transmitting and receiving predetermined RF frequencies to and from mobile units, each transceiver having an antenna for radiating and collecting the respective RF frequencies, the method comprising the steps of:

providing each of the plurality of transceivers with output power defining a cell substantially corresponding to a first Fresnel zone of the RF frequency; and

deploying the transceiver antennae at a distance from one another no greater than the diameter of the first Fresnel zone, the plurality of transceivers and antennae being located within a building enclosure having different propagation media, the step of deploying the transceiver antennae including the substep of

determining the first Fresnel breakpoint in accordance with the following equation;

d₀ =d=4(H-h₂)h₂ /λ

, wherein d₀ is the first Fresnel zone breakpoint, d is the distance between the transceiver antenna and the mobile antenna, h₂ is the height of the mobile antenna, H is the ceiling height of the building enclosure and is equal to the sum of h₁ and h₂, h₁ is the height of the transmit antenna, and λ

is the wavelength of the RF frequency.