In wireless communication, quadrature architectures are ubiquitous. They are severely hampered by down-conversion and the larger constellation sizes needed to achieve adequate throughput. Larger constellation sizes proportionally reduce signal space relative to noise while quadrature downconversion effectively doubles noise, leading to degraded receiver sensitivity. The resulting truncated range, compromised reliability, outsized spectral footprint, and large latencies superfluously limit communication.
Perhaps the most succinct figure of merit for all efficiencies in the wireless transmission is the ratio of the carrier frequency to bitrate, the closer to 1 the better. In that regard, an exciting new breakthrough in wireless communication developed by Gain ICs, instantaneous Wireless (iW), comes in at 2 cycles/bit with 2 constellations in contrast to comparable bitrate of 256 QAM (IEEE 802.11ac) at 57 cycles/bit. iW improves wireless transmission 28 times by this measure. The newest 5G potentially reduces to 28 cycles/bit, with 1 Gb/s at 28 GHz, a 14 times iW improvement. So at equal bitrates, the reduced frequency of iW achieves 144 times greater range, Figure 1, just by eliminating free space-loss from spherical spreading.
Figure 1. Simplified iW architecture, quantum advances in wireless communication.
The other wireless advance is inherently lower iW channel noise. With 2 iW constellations versus 256 constellations of QAM to achieve comparable bitrates, iW transmits to even greater ranges than achieved by reducing free-space loss, while increasing reliability by orders of magnitude as seen in Figure 2.
Figure 2. iW has orders of magnitude lower sensitivity to achieve same reliability as QAM.
The truncated range is a huge problem with 5G. While it can achieve the desired higher bitrates, it can only transmit roughly 1/100th the distance of previous generations at equivalent average bit energy. Bridging that gap is iW, which effectively achieves 5G bitrates at 4G distances in Figure 3, with 1000 times greater spectral efficiency.
Figure 3. iW achieves orders of magnitude greater transmit distance.
Spectral efficiencies of iW relative to quadrature can be seen in Figure 4. Both the math model and fast Fourier transform show an impulse function for the spectral footprint of iW. Figure 5 shows iW occupied bandwidth across carrier frequency, which is a nearly constant link spectral efficiency (LSE) of 28,200 b/s/Hz across all frequencies. This is roughly 1,000 times greater than LSE of quadrature architectures.
Figure 4. Low profile spectral impact of iW relative to quadrature.
Figure 5. iW occupied bandwidth across carrier frequency.
Software-defined radios (SDR), eliminate the limitations of quadrature and down conversion yet impede communication even worse. Flexibility over modulation schemes causes low bitrate due to Nyquist sampling. Spectra spread to increase bitrates, with frequency-dependent effects, like attenuation and absorption, degrading reliability. Lower transmit power is essential to avoid spectral contention, causing dropped links and blackout zones. These SDR detriments can be overcome via iW inherently higher bitrates, lower spectral footprint, and reduced noise.
The underlying technology which enables iW is an instantaneous loop (iL) with ideal phase coherence, shown in Figure 6. Depicted is iL tracking a modulated input to the fastest possible modulation rate, half of the reference or effectively a bitrate half the carrier frequency when used in wireless transmission.
Figure 6. Modulation and demodulation via ideal phase coherence.
As shown in Figure 7, an entire iW physical link can also be simulated—an impossible feat with 5G and QAM. Concerns over adverse physiological effects regarding 5G implementation are assuaged by iW, which has 10 times the wavelength of 5G and orders of magnitude less average bit energy of both 4G and 5G.
With negligible latencies, as seen in Figure 7, interference from multipath reflections can be entirely eliminated without significant degradation in bitrate. The direct path is ensured to be demodulated before any reflections arrive, thus being off when delayed paths arrive, effictively eliminating multipath interference.
Turnaround time, the transition from receive to transmit is optimally fast due to iW negligible latencies. Thus, frequency hopping 1,000+ times faster than current methods is achieved, providing secure or invisible communication. A new, two-way distance measurement is also now possible, achieving submeter locating accuracy as well as submeter per second velocity measurements via iW triangulation.
Figure 7. Simulation of entire iW physical link.
COMPARISON OF METHODS
Contemporary methods of quadrature radio frequency (RF) transmission involve down conversion to an immediate frequency (IF) or direct conversion which down converts to base frequencies directly (zero IF). iW eliminates down conversion entirely, performing neither direct nor zero IF. Thus iW reduces reception to essential operations only: amplify, filter and demodulate. Unlike SDR, which also eliminates down conversion and yet severely degrades performance in other ways, iW only enhances all other performance parameters.
The ongoing desperation in the wireless industry to get to high throughput reliably has led to 5G NR, which reverts back to lower frequencies of 4G. It pieces together multiple fragmented spectra in an attempt to essentially salvage 5G. Because of the mix of even higher frequency bands, the chief limitation (truncated range) is still pronounced. Table 1 of key wireless parameters shows the still far superior iW solution even without resorting to 4G/5G beamforming and multiple channels. As denoted in red text, when comparing against 4G, the previous generation, and 5G, the current generation, iW still achieves greater than 10 times the range and 10 times the power savings, while achieving 1,000 times greater spectral utilization at 100,000 times faster latencies. And all this, at lower power.
Table 1. Comparison of leading wireless communication via key wireless parameters.
While wireless communication is currently grappling with huge limitations in the attempt to get to higher capacity, essentially higher and reliable bitrates with greater spectral efficiencies, there is now a breakthrough technology to achieve just that. A comprehensive development effort has revealed that, indeed, iW does achieve higher and reliable bitrates with far greater spectral efficiencies.
These advanced capabilities also enable entirely new wireless applications and the potential to open up entirely new wireless markets. Please contact Gain ICs to find out more.