Chiar dacă unii sunt extrem de supărați, mie îmi place noul Palm: este un telefon cu o mică tentă de smartphone (spre deosebire de restul produselor de pe piață, unde sunt smartphones cu o mică tentă de telefon), aduce o funcționalitate de bază și… cam aia e.
Eu sper să includă o cameră decentă și o baterie ce-i asigură o autonomie solidă de 2-3 zile, astfel încât va fi un mic succes.
Doar că…
along with the pathetic eight hours of battery life, will certainly make me want to use the Palm 2018 less, if nothing else.
Deci nu chiar 
Poza asta mi-a adus aminte de o treabă: își mai aduce cineva aminte că majoritatea telefoanelor de la începutul anilor 2000 veneau cu o găurică în carcasă ce-ți permitea să-l „legi” de mână? Când s-a renunțat la treaba asta? De ce?
Vrei telefon sau breloc?
cand au inceput sa apara gentile pt telefoane mobile
La găurică probabil s-a renunțat fiindcă nu o mai folosea nimeni odată cu creșterea în dimensiune din nou a telefoanelor, plus că există carcase protectectoare care au funcția asta.
sau cand au inceput sa le faca din ce in ce mai subtiri.
Sau când au început să le facă water proof
Mie o sa-mi placa asta, cand (daca) apare:
@Gigel Anonimu’: unde găsești tu scamurile astea?
Undele radio pot alimenta chestii, dar ai nevoie de…. Împământare! Așa că, dacă te deranjează să stai cu o tijă de cupru de câțiva metri înfiptă în pământ udat cu saramură, e cam vrăjeală
@Ionuț Staicu: Niste baieti (sau fete) de la University of Wasinghton:
https://www.firstpost.com/tech/news-analysis/cellphone-without-batteries-invented-by-university-of-washington-researchers-3835817.html
@Gigel Anonimu’: Serios?
Fun fact: știai că într-o stație de emisie radio sau TV un bec se aprinde dacă-l ții în mână de fasung?
@Ionuț Staicu: Dap, serios!
N-am zis ca-i un produs viabil acum, ci:
„Mie o sa-mi placa asta, cand (daca) apare:”
E ca si cum ai avea pretentia ca primul prototip de telefon facut acu’ vreo 150 de ani sa fie la standardele telefoanelor de acum. Really?
Dintr-un alt articol:
„The research team’s next objectives are to improve the battery-free phone’s operating range…..”
Din studiul publicat de ei:
„our basestation currently transmits 30 dBm output power in the 915 MHz ISM band; the maximum power allowed by the FCC in the unlicensed bands. However, in licensed cellular bands, the basestation can transmit orders of magnitude higher power which will significantly increase the operating range of the analog backscatter microphone”
si
„our current prototype repurposes an existing electret microphone (designed for voltage output) for analog backscatter. This creates only one-tenth of the maximum possible differential radar cross-section, which results in a weak analog backscattered speech signal.
We believe that a microphone designed to maximize the differential radar cross-section will also increase the performance and operating range of analog backscatter microphone. ”
si
„our USRP based basestation suffers from self-interference that limits backscatter performance. One can leverage recent progress on full-duplex radios or physically separate transmitter and receiver to improve the quality of the analog backscattered speech.”
si
„raditional networks use a combination of time division multiplexing (TDM)
and frequency division multiplexing (FDM) to share the wireless spectrum across large number of devices. Our battery-free system can be scaled along similar lines”
.
[tot studiul publicat de ei](http://delivery.acm.org/10.1145/3100000/3090090/a25-talla.pdf?ip=85.204.250.252&id=3090090&acc=CHORUS&key=4D4702B0C3E38B35%2E4D4702B0C3E38B35%2E4D4702B0C3E38B35%2E6D218144511F3437&__acm__=1539866436_8bfa6b8ec5cdf1a70ca52c1f89ccebdb)
Snippet-ul relevant:
**Operating Range.**
The current implementation of battery-free phone operates up to 50 feet with photodiode power. The operating range of our phone is determined by the performance of the analog backscatter microphone, which can be improved by using multiples techniques: First, our basestation currently transmits 30 dBm output power in the 915 MHz ISM band; the maximum power allowed by the FCC in the unlicensed bands. However, in licensed cellular bands, the basestation can transmit orders of magnitude higher power which will significantly increase the operating range of the analog backscatter microphone. Second, our current prototype repurposes an existing electret microphone (designed for voltage output) for analog backscatter. This creates only one-tenth of the maximum possible differential radar cross-section, which results in a weak analog backscattered speech signal.
We believe that a microphone designed to maximize the differential radar cross-section will also increase the performance and operating range of analog backscatter microphone. Third, our USRP based basestation suffers from self-interference that limits backscatter performance. One can leverage recent progress on full-duplex radios or physically separate transmitter and receiver to improve the quality of the analog backscattered speech.
**Networking multiple devices.**
Traditional networks use a combination of time division multiplexing (TDM)
and frequency division multiplexing (FDM) to share the wireless spectrum across large number of devices. Our battery-free system can be scaled along similar lines. The basestation can co-ordinate communication with different devices by assigning time slot and frequency channel to each device. Multiple backscatter devices can then simultaneously transmit data and analog speech by using different (assigned) frequency offset to backscatter data and receive speech in different time slots. Exploring this however is not in the scope of this paper.