CPC Class H04W

A system of mobile devices that reduces the transmission strength of outgoing signals originating from a handheld device, and sends such signals to a second device, situated near or on a lower-body location, where the signals may be amplified to the current permitted maximum transmission strength vis-a-vis the brain (SAR), or above that level to the greater maximum strength permitted in the areas of, e.g., the feet and ankles, where the signal is then sent outward. The devices divert radio frequency (RF) radiation exposure downward toward the lower extremities. The intelligence and power of the devices may be split between two or more devices, resulting in longer use time, deeper and more complex computing capability, and fewer disruptions due to power. In addition, a benefit in one or more embodiments is better, more reliable reception, due to the use of two or more coordinated receiving antennas.

Various aspects described herein relate to low-loss multi-band multiplexing schemes for a wireless communications system, for example, a 5th Generation (5G) New Radio (NR) system. In an aspect, a multiplexer for multi-band wireless communications comprises at least one tuning component configured to transmit or receive at least one signal within a frequency band that is selected from a plurality of frequency bands. The multiplexer further comprises at least one combining component, communicatively coupled with the at least one tuning component, configured to transmit or receive the at least one signal within the selected frequency band. In an aspect, the at least one tuning component is integrated on a chip and the at least one combining component is not integrated on the chip.

A method of transmitting a message using a slow hopping anti-jam waveform, includes generating a sequence with a cryptographic hash function; transmitting, for a predetermined dwell time, a first portion of the message on a first channel having a first baseline frequency; choosing a second channel having a second baseline frequency based on the generated sequence, the second baseline frequency being offset from the first baseline frequency; and transmitting, for the predetermined dwell time, a second portion of the message on the second channel having the second baseline frequency; wherein the two transmitting steps occur sequentially.

A system and method for detecting passive intermodulation (PIM) interference in cellular networks are provided that do not require the base station or any sectors of it to be taken offline, that eliminate the need for a technician to make a visit to the cellular site to perform PIM testing, that enable multiple uplink connections to be remotely tested simultaneously, that enable cellular networks to be tested that do not have an accessible connection point to the RF chain, and that enable gradually deteriorating performance due to PIM interference and intermittent PIM interference problems to be detected.