Telogy Networks, Inc.

Combasis Technology, Inc.

Hyokang Chang

Seok Ho Kim

Ashim K Roy

Limiting RF signal reception outside of a perimeter boundary to enhance security in a wireless network. A central jamming controller (CJC) communicates with one or more access points within a wireless network to determine if link activity is present within a cell controlled by a specific access point. Link activity comprises transmissions from an authorized communication device (ACD) to the access point and transmissions from the access point to the ACD. When link activity is detected, the CJC directs a jamming antenna system to produce a jamming signal and to transmit the jamming signal outside of the perimeter boundary defined by the WLAN. The jamming signal comprises noise transmitted within the bandwidth of the channel being used by the access point and the ACD to communicate within the cell. An unauthorized communication device (UCD) outside of the perimeter boundary will be prevented from receiving the communication between the access point and the ACD because of the jamming signal.

RF firewall for a wireless network

A memory configuration scheme that enables parallel decoding of a single block of turbo-encoded data is described. In this scheme a single code block is divided into multiple subblocks and decoding is performed on subblocks in parallel. The turbo decoder memory is configured so that subblock decoders can access the common memory resources independently of each other. This scheme is different from existing parallel decoding schemes in that it achieves the parallel implementation by applying multiple decoders to a single code block, not by assigning multiple decoders to multiple code blocks. The advantages of this scheme include minimum memory requirement and minimum decoding latency. The minimum memory requirement results from the fact that it needs memory resources only for a single code block regardless of the number of decoders used. The decoding latency is minimum since decoding of a code block is over when decoding on subblocks is completed.

Memory configuration scheme enabling parallel decoding of turbo codes

A codeword forcing technique is applied which provides gradual degradation of an audio output during fading such that analog degradation in a fading signal environment is simulated. The system may be used in conjunction with digital cordless telephones where gradual degradation of a 32 Kbit/s ADPCM signal is obtained by indirectly detecting a transmission bit error rate, The bit error rate detection is accomplished by sensing the occurrence of an invalid all-zero code, Codeword forcing techniques are then applied to compensate for the inaccurate transmission and associated noise level,

Adaptive differential pulse code modulation system with transmission

A method of passing tones transparently over narrowband channels without having to detect the tones at the transmit side is described. This method requires neither separate handling of tones for the transmission purpose, nor prior knowledge of the characteristics of the signaling tones used. It is a relatively general method that can be applied to systems using a variety of speech coding techniques utilizing a frame structure.

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Potomac, MD, United States of America

Hyokang Chang