Host-generated channel plans for wideband wireless audio carriers: spread groups across the band and compact groups in four-TV-channel windows, intermodulation products as width sums, a band floor held at the -40 dB skirt plus a margin, and firmware tables with precomputed two-radio pair advice that the operator picks from

Abstract

A host program, never the transmitter or the receiver, computes group tables per radio mode ("profile") and per regulatory region, and writes them as text tables that a build step compiles into firmware constants. The firmware contains no planning code and does no intermodulation arithmetic. Carriers have a centre and a width (declared occupied, -30 dB and -40 dB). An intermodulation product sum(k_i f_i) (with sum(k_i) = 1) occupies sum(|k_i| W_i) centred on sum(k_i f_i). A set of carriers is compatible when every term (every carrier pair, and every product against every carrier that is not one of its sources) has an edge-to-edge gap at least its guard. Two kinds of group per profile: spread groups G1..Gn, each the largest compatible set found over the whole planning span (470-663 MHz cut to the region), among candidates at least half an occupied width from every channel of earlier spread groups, at most 12 groups of at least 4 channels, numbered by size; and compact groups C1..Cn, one per window of four consecutive TV channels (24 MHz), each holding as many channels as the window can, packed as closely as the guards allow, for venues where only part of the band is clear. A floor: a centre is refused unless its widest known edge (the largest of the occupied, -30 dB and -40 dB widths) is at least 100 kHz above 470.000 MHz. The tables record the lowest centre this allows for each profile. Each firmware table lists every channel its groups use, the groups, and the sparse list of channel pairs that two radios of one transmitter should not run together, with the worst margin. A lookup returns, for two radios' channels, "same channel", "compatible", "incompatible (margin)" or "not in the table". This is advice shown to the operator; the transmitter runs whatever the operator picks. The operator picks the group, the channel and the radio mode. Nothing in the transmitter or receiver picks, ranks or changes a frequency from the tables, and no group or channel number is ever transmitted. Defensive publication, placed in the public domain as prior art. License: CC BY 4.0.