orthogonal adj. 1.直角的,互相垂直的;正交的;直交的。 2.(統(tǒng)計數(shù)字)互不相關(guān)的。 an orthogonal section 正(交)剖面。
variable adj. 1.易變的,變化無常的,無定的 (opp. constant, steady)。 2.可變的,能變的;變換的。 3.【數(shù)學(xué)】變量的;【天文學(xué)】變光的;【生物學(xué)】變異的。 Prices are variable according to the exchanges. 物價跟著匯率變動。 a man of variable character 反復(fù)無常的人。 a rod of variable length (伸縮)如意棒。 a word of variable construction 可以作種種解釋的詞。 variable capital 可變資本。 a variable budget 臨時預(yù)算。 n. 1.易變的東西。 2.【數(shù)學(xué)】變量,變數(shù),變項,變元 (opp. constant);【天文學(xué)】變星 (=variable star);【航海】(方向不定的)變風(fēng),不定風(fēng) (opp. trade wind); 〔pl.〕 (貿(mào)易風(fēng)帶中的)變風(fēng)帶。 adv. -ably ,-ness n.
In order to support multi-rate transmission in ds-cdma, many cdma techniques such as multi-code ( mc ) scheme, orthogonal variable spreading factor ( ovsf ) and variable modulation have been used 在ds-cdma系統(tǒng)中多速率傳輸?shù)姆椒ㄓ泻芏喾N,例如多碼方案(mc-cdma),正交可變擴頻增益方案(ovsf)和多調(diào)制方案等。
First of all, correlation properties of orthogonal variable-length spreading sequences are analyzed and new closed-form expressions of mai of the cdma systems are derived in terms of aperiodic partial correlation of variable-length sequences . then, the self-interference ( si ), mai and bit-error-rate ( ber ) performance of the desired user in a multi-rate cdma system are analyzed 本文首先分析了正交變長擴頻序列的相關(guān)特性,導(dǎo)出了以變長序列非周期部分相關(guān)表示的cdma系統(tǒng)多址干擾(mai)新的分析表達式,并分析了多速率碼分多址系統(tǒng)中,期望用戶的自干擾(si)、多址干擾和誤比特(ber)性能。
Concerning with the direct sequence ( ds ) cdma system, this thesis focuses on several issues related to orthogonal spreading sequences and amc, including correlation properties of orthogonal variable-length spreading sequences and their effects on ds cdma system performance, performance of multicarrier ( mc ) ds cdma system with generalized orthogonal ( go ) sequences, adaptive modulation with throughput maximization, performance of adaptive turbo-qam coded modulation in generalized fading channel and performance of amc in wcdma high speed downlink packet access ( hsdpa ) 針對直接序列碼分多址(dscdma)系統(tǒng),本文主要研究了正交擴頻序列和自適應(yīng)調(diào)制編碼若干問題,包括正交變長擴頻序列的相關(guān)性及其對dscdma系統(tǒng)性能的影響、采用廣義正交(go)序列的多載波直接序列碼分多址(mcdscdma)系統(tǒng)性能、吞吐量最大化自適應(yīng)調(diào)制、自適應(yīng)turbo-qam編碼調(diào)制在廣義衰落信道中的性能,以及wcdma下行分組接入(hsdpa)中自適應(yīng)調(diào)制與編碼性能五個方面。