Abstract: High gain, multi-pattern multiple-input multiple-output (MIMO) antenna systems are disclosed. These systems provide for multiple-polarization and omnidirectional coverage using multiple radios, which may be turned to the same frequency. The MIMO antenna systems may include multiple high-gain beams arranged (or capable of being arranged) to provide for omnidirectional coverage. These systems provide for increased data throughput and reduced interference without sacrificing the benefits related to size and manageability of an associated access point.

Abstract: A PIN diode network includes a parallel inductor. In the off state of the PIN diode, the inductor forms a resonant tank circuit in parallel with the PIN diode. The inductor is selected based on the stray capacitance of the PIN diode so that the self resonant frequency (SRF) of the tank circuit is at or near the desired operating frequency. At the operating frequency, the impedance of the tank circuit is essentially infinite. At the operating frequency, isolation is improved for the PIN diode network as compared to a PIN diode alone. The PIN diode network allows a lower specification PIN diode to operate with higher isolation. The PIN diode network allows a lower specification PIN diode to operate at a higher frequency than would otherwise be possible due to intrinsic stray capacitance of the PIN diode.

Abstract: A circuit board for wireless communications includes communication circuitry for modulating and/or demodulating a radio frequency (RF) signal and an antenna apparatus for transmitting and receiving the RF signal, the antenna apparatus having selectable antenna elements located near one or more peripheries of the circuit board. A first antenna element produces a first directional radiation pattern; a second antenna element produces a second directional radiation pattern offset from the first radiation pattern. The antenna elements may include one or more reflectors configured to provide gain and broaden the frequency response of the antenna element. A switching network couples one or more of the selectable elements to the communication circuitry and provides impedance matching regardless of which or how many of the antenna elements are selected.

Abstract: Systems and methods for authentication using paired dynamic secrets in secured wireless networks are provided. Each authenticated user is assigned a random secret generated so as to be unique to the user. The secret is associated with a wireless interface belonging to the user, so that no other wireless interface may use the same secret to access the network. The secret may be updated either periodically or at the request of a network administrator, and reauthentication of the wireless network may be required.

Abstract: A system and method for a wireless link to a remote receiver includes a communication device for generating RF and an antenna apparatus for transmitting the RF. The antenna apparatus comprises a plurality of substantially coplanar modified dipoles. Each modified dipole provides gain with respect to isotropic and a horizontally polarized directional radiation pattern. Further, each modified dipole has one or more loading structures configured to decrease the footprint (i.e., the physical dimension) of the modified dipole and minimize the size of the antenna apparatus. The modified dipoles may be electrically switched to result in various radiation patterns. With multiple of the plurality of modified dipoles active, the antenna apparatus may form an omnidirectional horizontally polarized radiation pattern. One or more directors may be included to concentrate the radiation pattern. The antenna apparatus may be conformally mounted to a housing containing the communication device and the antenna apparatus.

Abstract: An access point of a communications network is disclosed configured to receive a multicast or broadcast packet from a source. The access point converts the multicast or broadcast packet into a unicast packet addressed to a station associated with the access point. The access point then transmits the unicast packet over the communications network from the access point to the station. The access point further may determine a minimum data rate by which the access point may transmit the multicast or broadcast packet to the station and determines an effective unicast rate for transmitting the unicast packet to the station. If the effective unicast rate does not exceed the minimum data rate, the access point does not transmit the unicast packet to the station and transmits the multicast or broadcast packet.

Abstract: A circuit board for wireless communications includes communication circuitry for modulating and/or demodulating a radio frequency (RF) signal and an antenna apparatus for transmitting and receiving the RF signal, the antenna apparatus having selectable antenna elements located near one or more peripheries of the circuit board and selectable phase shifting. A switching network couples one or more of the selectable elements to the communication circuitry and provides impedance matching regardless of which or how many of the antenna elements are selected, and includes a selectable phase shifter to allow the phase of the antenna elements to be shifted by 180 degrees. The phase shifter includes a first RF switch and two ¼-wavelength delay lines of PCB traces or delay elements and a second RF switch. The phase shifter selectively provides a straight-through path, a 180 degree phase shift, a high impedance state, or a notch filter.

Abstract: A horizontally polarized antenna array allows for the efficient distribution of RF energy into a communications environment through selectable antenna elements and redirectors that create a particular radiation pattern such as a substantially omnidirectional radiation pattern. In conjunction with a vertically polarized array, a particular high-gain wireless environment may be created such that one environment does not interfere with other nearby wireless environments and avoids interference created by those other environments. Lower gain patterns may also be created by using particular configurations of a horizontal and/or vertical antenna array. In a preferred embodiment, the antenna systems disclosed herein are utilized in a multiple-input, multiple-output (MIMO) wireless environment.

Abstract: A system and method for a wireless link to a remote receiver includes a communication device for generating RF and an antenna apparatus for transmitting the RF. The antenna apparatus comprises a plurality of substantially coplanar modified dipoles. Each modified dipole provides gain with respect to isotropic and a horizontally polarized directional radiation pattern. Further, each modified dipole has one or more loading structures configured to decrease the footprint (i.e., the physical dimension) of the modified dipole and minimize the size of the antenna apparatus. The modified dipoles may be electrically switched to result in various radiation patterns. With multiple of the plurality of modified dipoles active, the antenna apparatus may form an omnidirectional horizontally polarized radiation pattern. One or more directors may be included to concentrate the radiation pattern. The antenna apparatus may be conformally mounted to a housing containing the communication device and the antenna apparatus.

Abstract: An antenna apparatus comprises selectable antenna elements including a plurality of dipoles and/or a plurality of slot antennas (“slot”). Each dipole and/or each slot provides gain with respect to isotropic. The dipoles may generate vertically polarized radiation and the slots may generate horizontally polarized radiation. Each antenna element may have one or more loading structures configured to decrease the footprint (i.e., the physical dimension) of the antenna element and minimize the size of the antenna apparatus.

Abstract: A system and method for a wireless link to a remote receiver includes a communication device for generating RF and a planar antenna apparatus for transmitting the RF. The planar antenna apparatus includes selectable antenna elements, each of which has gain and a directional radiation pattern. The directional radiation pattern is substantially in the plane of the antenna apparatus. Switching different antenna elements results in a configurable radiation pattern. Alternatively, selecting all or substantially all elements results in an omnidirectional radiation pattern. One or more directors and/or one or more reflectors may be included to constrict the directional radiation pattern. The antenna apparatus may be conformally mounted to a housing containing the communication device and the antenna apparatus.

Abstract: A circuit board for wireless communications includes communication circuitry for modulating and/or demodulating a radio frequency (RF) signal and an antenna apparatus for transmitting and receiving the RF signal, the antenna apparatus having selectable antenna elements located near one or more peripheries of the circuit board. A first antenna element produces a first directional radiation pattern; a second antenna element produces a second directional radiation pattern offset from the first radiation pattern. The antenna elements may include one or more reflectors configured to provide gain and broaden the frequency response of the antenna element. A switching network couples one or more of the selectable elements to the communication circuitry and provides impedance matching regardless of which or how many of the antenna elements are selected.